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Valve extender snapped off Yesterday I crashed, and somehow the front wheel landed on a rock or something that made my valve extender break. The bottom part of it is still stuck in the valve it extended. It's a tubular tire so just changing tube is not an option. Any suggestions on how to get it out? <Q> Then put one more piece of duct tape over the top of the valve. <S> Draw a line across the top pf the valve with a marker pen. <S> Get a miniature hack-saw and very gently <S> start cutting a groove down into the top of the valve <S> (perpendicular to the rim). <S> Use a competent friend to hold the wheel upright and very still while doing this (may even help to add more duct tape to hold the wheel down on the floor). <S> Once the groove is deep enough to hold the blade, remove enough of the duct tape so you can see how far down the rim is. <S> Keep cutting down to the limit of your confidence (i.e. don't cut into the rim). <S> Now use a thin-ended screw-driver to unscrew the valve. <S> If the cut is to narrow to easily fit your screw-driver into, use a narrower blade (like a bread knife) until you have the valve down almost flush with the rim. <S> If that is all too scary, take it to your LBS. <A> This looks like a very straightforward job for an easy out. <A> I've never faced this situation, so I can only speculate. <S> That said: Remove tire. <S> Apply lubricant around the edge of extender remnant to facilitate removal-- <S> something like WD40 should suffice. <S> When that doesn't work, set the rim on two pieces of scrap wood with the valve opening between them; have a friend hold the rim in place while you tap on the extender remnant with a mallet. <S> You may need something to drive it all the way out, like a large nail or a nailsetter.
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Cover the rim all around the valve with a thick layer of duct tape until the tape is almost level with the exposed surface of the valve. Attempt to pop out the extender remnant with your thumb.
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Difference between two drivetrains with the same gear ratio? Given two identical, fixed-gear bicycles, one with a 36/12 gear combination and another with 48/16, will there be any noticeable difference when pedaling these two bicycles? I understand there may be some negligible differences due to differing amounts of chain wrap on the cogs, etc. I have a friend who alleges that, despite those bikes having identical gear ratios, the 48T chainring will be "better" for a rider preferring a lower cadence and the 36T chainring will be "better" for a rider preferring a higher one. I've attempted to explain to him that this would require the bikes to somehow have differing amounts of development per pedal rotation, which they do not as I have tried to demonstrate here: http://www.gear-calculator.com/?GR=SGLS&KB=36&RZ=12&UF=2240&TF=90&SL=2.6&UN=KMH&GR2=SGLS&KB2=48&RZ2=16&UF2=2240 Please help me win this argument! <Q> The gear ratio is exactly the same, the only possible difference is in the efficiency of the power transmission. <S> Big/Big is generally more efficient, so it should be better for both, unless there is some reason that greater power losses in the transmission chain help "spinners". <S> I don't see how that translates to masher vs spinner though. http://www.ihpva.org/HParchive/PDF/hp50-2000.pdf <A> so there is more loss to friction as the links bend. <S> It ignores the fact that you move more chain when using Big/Big. <S> The 48/16 will move 33% more chain through the gears than the 36\12. <S> Each link will move about 3/4 of the angle. <S> Friction on moving is often divided into breakaway and continuous friction. <S> You have the same amount of continuous- <S> half again as much for the 36/12 but 2/3 as often, but only 2/3 as many breakaways. <S> Tiny compared to air resistance. <S> But the bottom line is that in this model you want small gears, like 36/12. <A> Larger sprockets are slightly more efficient. <S> According to https://www.cyclingpowerlab.com/DrivetrainEfficiency.aspx , you may get 0.5% more effective Watts, which would translate into something like a 0.2% speed gain. <S> At an average of 20kmh, that is 40 meters per hour... <A> Taking physics into consideration: smaller sprockets mean shorter chain and in total less weight thus less energy needed to cover the distance, however there is more friction on the chain links (power loss) and more tension on the chain so probably stronger chain might be required. <S> larger sprockets mean longer chain thus more weight. <S> But there is less tension and less friction on the chain itself. <S> Whether the lower friction on the chain compensates for more weight of the drive - I have no idea <S> but I reckon it won't. <S> Whether a stronger chain is needed for smaller sprockets - I doubt as lengthwise the chain is pretty strong. <S> It gets weak from flexing it sideways. <A> The efficiency of the system warbles inconsequentially. <S> Bigger gets you less frictional loss per link, but more links and more weight. <S> That aspect comes out in the wash, and if you really want to figure it out conclusively you would need full information on materials, lubricity, etc. <S> However, the part of this that actually has an impact on function is that bigger gears and more chain wear longer, and so they're more economical and all else equal will be fresh/unworn longer, making them more efficient and less maintenance-intense. <S> Counterbalancing wear is that some disciplines care a lot about obstacle and/or frame/component clearance <S> Those are the two aspects that lead to the different genres of bike using the sizes they do, wear life versus clearance.
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The claim that Big/Big is more efficient depends on the fact that the links in the chain bend more when going around smaller gears I'd say if the cranks are the same length and the wheels a and tyres are the same size there will be no difference in cadence. So they will potentially feel different if you can notice the difference ( pretty small ) in the efficiency of the drive train.
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Very nonstandard question: Is there any way to widen a tire by combining it with some other tire (cut and re-glue)? Brace yourself - this is not normal. I have an old 22" rim (37-501, 22x1-3/8) and all I can get is skinny tires for it. But I'm an idiot and I really want a wider tire on that rim. I want it so bad I am grasping at straws for ideas. So here's the thought: Get a new tire (22x1-3/8)Get a new BMX 22" tire (which is NOT gonna fit my rim) Cut the skinny one's beads off with about 1" of rubber above it.Cut the bead off the BMX tire very low. Glue BMX tread to old-school beads. Viola! a 2" wide tire for the old 22" rim. Yeah, I know this is nuts. But CAN it be done and become whole again? Maybe, just maybe, someone here knows if this has ever been done. Please let me know. <Q> I don't think what what you are proposing to construct would not be anywhere near strong enough to function properly as a tire. <S> Tires are not just molded rubber. <S> They are contain a casing of continuous fibers that enables then to withstand inflation pressures and lateral forces caused by cornering. <S> https://en.wikipedia.org/wiki/Bicycle_tire#Construction <S> By gluing parts of two tires together you would not have a continuous casing running through the tire. <A> But you'll pay an incredible amount of money for it. <S> Companies like Hoosier Tire will make any tire you like. <S> They specialise in vehicles like cars and motorbikes, but money talks if you're paying for a custom build. <S> I have no experience of the iterative process of tyre design, so you might have to commit to a minimum quantity, or accept the first few might not match the required tolerances. <A> Another option that may work is dual rims, aka Dualies. <S> Again a concept from the automotive world, this is where two rims are mated to each side of a vehicle's axle, giving four rims and four tyres per axle. <S> The main purpose is increased load capacity, with secondary advantages of spare wheels for flat tolerance, and increased road contact for more grip. <S> This would be a high-spoke-count wheel. <S> I don't think you would have to weld the two rims together, but Downsides are it would track straight and would resist turning aggressively. <S> Your turns would have to be super slow and vertical, or you have to lean and get onto the inside tyre only, leaving the other suspended in the air. <S> Rim brakes would flat out not work, so you have to have a disk brake. <S> And your fork and frame clearances would need to be enormous to let two wheel rims and two skinny tyres sit side by side. <S> Example of dual wheel rims on a bike. <S> This is a custom-built rig for polar snow riding. <S> Chain runs through between the rims so they're separate, but the front rims are together. <S> Tyre pressure is given as only 2 PSI. <S> From https://gearjunkie.com/4-wheel-bike-antarctica-van-weelden <A> The obvious weak point is the joint, unless that adds enough in terms of diameter that you don't have to cut the outer tire. <A> I've just performed a quick search in the country of the bicycles - 22" tyres in 1.75 width are very common, the 1.95 are the widest I've found. <S> All are still reasonably priced (less than €20 a piece). <S> Would that not be wide enough for you? <S> Apparently the tyres I've found are far to small (44mm in diameter) to fit the OP's rims. <S> The comments below explain the issue. <S> My apologies for false information.
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The only solution I can think of that might have a chance of not killing you would be to take the existing tire, that fits the rim, grind down the tread, and then glue the wider tire around the outside (like retread truck tires.). You can have any tire size shape or colour you want. In your case you would want two 22" rims side by side, each with 28 or 32 spokes, laced to a single hub with 56 or 64 holes.
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Does sunlight damage helmet? Lately I am wearing my helmet also on my daily commute to work. Of course I don't wear it while sitting at my desk, and it sits on a drawer next to the window, where in the afternoon it is exposed to sunlight with little or no air flow. Can this lead to long term damage of the helmet? The helmet shell is white. <Q> I was able to find one study that comes close to addressing this: <S> Age Does Not Affect the Material Properties of Expanded Polystyrene Liners in Field-Used Bicycle Helmets . <S> You'd need to pay to read the whole thing, but the abstract and title are clear enough. <S> It's not clear from the abstract whether the helmets tested had been exposed to UV or not. <S> According to the Bicycle Helmet Safety Institute , UV exposure is not a big concern because helmets are treated with UV inhibitors, and unless there's visible signs of cracking, talk of replacing helmets on a regular schedule is marketing hype. <S> The EPS foam makes up the bulk of the helmet, of course, but it's not the only part, and if the shell, pads, or straps are damaged or degraded, that might be a reason to replace it. <A> Helmets are intended to be worn while cycling in the sun, so they have to be ok. <S> Now that in many places it's normal to leave helmets on bikes stored outside all day. <S> Plausible damage mechanisms are UV and heat. <S> Through glass there will be less UV than outside, so we can dismiss that indoors. <S> Heat is harder to dismiss but if you're in a temperate place it's not likely to get as hot as outside in full sun. <S> Anyway your helmet is white <S> so won't absorb much heat from the sun. <S> The lack of airflow isn't a big deal. <S> There's not much airflow riding slowly especially as your head blocks it. <A> Yes, sunlight may affect helmet performance. <S> It catalyzes the material-aging process. <S> According to the Snell Foundation, a motorcycle helmet should be replaced every five years . <S> Looks like this recommendation should also apply to bicycle helmets.
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Sunlight will not break your helmet after several rides, but years of exposure may substantially affect the performance of the helmet during an accident.
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Record Bags for Bikes I do a local community radio show once a week as a volunteer that I can cycle to but the issue is a often take vinyl records with me. Anyone know of bags/panniers that can hold some 12" vinyl? Cheers <Q> Or modify the bag yourself to attach to a pannier by stitching some hooks or loops of Velcro to the sides. <S> Most pizza bags are 18" x 18" and about 5" deep so plently of room for records and maybe a snack for later ;) <S> You can buy them online for rather cheap. <A> Try using a milk crate bungee corded to your rack. <A> @NewBikeBoy - what is your location? <S> I've just checked - basically <S> any type of rear-rack bags sold in the Netherlands will suit your needs as they are 35x31x10 cm (12" record is 30cm in diameter). <S> The following link is purely as illustration, it is not meant as an advertisement of certain product or seller: <S> https://www.internet-bikes.com/176237-niet-verkeerd-dubbele-fietstas-metal-grijs-22-liter/ Edit: apparently the above mentioned product is not longer available from this retailer. <S> Since we are not advertising any product on this site, for those who are interested in those particular bags I'd suggest to run a search with your favourite search engine for "Niet verkeerd dubbele fietstas" - there are enough models and resellers available.
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You could also buy a pizza delivery bag and bungee strap it to a front or rear rack.
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Outside of Schrader valve is inflating. This isn’t right, is it? My wife has an old Moulton bike. I was inflating her tyres (small wheels, tyre imprinted ‘50 pounds’, when the rubber surround of the Schrader valve started inflating also. It all seems quite airtight, but I don’t think it should do this, and I wonder why it is happening, and what I should do - replace the inner tube, or just let it get on with it? I don’t want it to blow out when we are a few miles away from home. Anybody seen this? Any thoughts and advice? <Q> I haven't come across this before <S> but it's not right. <S> It sounds like the valve coating is coming unstuck from the metal part of the valve. <S> If that fails it would be quite likely to fail suddenly which could be painful. <S> Time for a new tube <A> Well, you were quite right Chris H - I went out the next day to look at it, the tyre was flat, and the metal Schrader valve was hanging out of the tube at a crazy angle with the rubber bit that goes up the side of the valve <S> split right open. <S> So I replaced the tube - a 20in Kenda 1 3/8 - with a Raleigh one. <S> Nominally the same size, but as you can see from the picture, actually somewhat fatter, with 1.75 and 1 3/8 printed on it, though 1 3/8 is actually 1.375, of course. <S> Anyway, I got the new tube in OK - the tyre itself seemed fine - and <S> it’s doing the job, so I guess there is some leeway in sizing. <S> The Raleigh inner shown is the spare, and has gone in the bike bag. <S> The Kenda and its valve, after their moment in the spotlight, have gone in the bin, though I salvaged the valve cap. <S> You can’t have too many valve caps :) <S> One <S> again, thanks for all the help and suggestions. <A> I'm guessing you have the sidewall of the tyre inflating sideways, and not the tube inflating through the valve stem hole. <S> Also look at the sidewall for any form of tear, a couple of millimetres is all it needs to start stretching strangely. <S> If this is the case, you need a new tyre.
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Generally this is a failure of the tyre bead, and its no longer seating properly in the rim.
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Why does shifting under power affect shift quality? I recently was attempting to shift up a hill and observed that The shifting levers on the handlebars displayed significant resistance to my pushing them. Despite several rotations of the crank, the bicycle had not shifted gears. Googling around, I've seen people claim that pedaling under power increases chain tension and that this chain tension will affect how easily the chain moves between gears. Intuitively, this does not make sense to me, as how easily the chain moves orthogonal to the direction of travel (i.e., the ease of shifting) would seem to be independent of the chain tensions parallel to the direction of travel. This seems to imply there's a causal relationship between the relative magnitudes of these forces. Moreover, given that the chain itself is the same length regardless of the power transmitted, it's unclear to me how pedaling increases chain tension. Is it that one part of the chain becomes more tense, and the other becomes less tense? A free-body diagram type explanation would be very helpful. How might one understand or model the shifting action and mechanism in a way that explains why chain tension affects shifting? <Q> There may be other factors that affect "shift quality", if I understand what you meant correctly, but the most significant by far is “direction of force applied. <S> Basically for a gear to change the mechanism <S> just pushes the chain “off rail” enough in the direction of the new gear. <S> When the chain has a higher tension applied on it the derailleur doesn’t have enough strength to push the chain “off the rail”. <S> (Derailleur is the name of the part the pushes <S> the chain)If you still haven’t understood, imagine a line stretched between two fixed poles, if it is loose and you push it to the side it will move some, if it has a higher tension and you push to the side with the same strength and direction than before it will move less. <S> And the tighter the line the less to the side it would move. <S> A gear system has a minimum distance that it needs to move to the side so it can change gears. <S> More advanced, modern and obviously expensive <S> have over time placed gears closer to each other and shaped individuals to make the “derailing” need a smaller push in a new direction, requiring less strength to push the chain and as a whole make the process more smooth. <S> If you didn’t understand something just ask. <A> I would suggest considering two power components: (1) rotational speed and (2) torque. <S> It should be naturally obvious that these two principles will impact the ability of a chain to jump across sprockets. <S> As rotational speed tends towards zero, shifting becomes problematic. <S> As torque increases, the chain will require more lateral force to be lifted above a sprocket’s cog. <S> Going uphill while maintaining a reasonable cadence has limited negative impact on modern cassettes that have sculpted cogs to promote easier shifting. <S> However, these designs are challenged if you are a masher (slow cadence + high torque). <S> In the old days, riders would put less pressure on the pedals to reduce torque while keeping a high cadence. <S> Today, higher end components work well under high torque as long as cadence stays above... <S> I’d venture 60. <A> Perhaps when you think of tension you are thinking of something like a rubber band or spring where tension produces very visible increase in length. <S> The individual metal chain links do in fact stretch when under pedaling tension <S> , we just cannot see it because the amount of deformation is so small. <S> If you take a long, flexible item such as a chain, rope or wire and put it under tension, there is in fact a force needed to push it sideways - think of a drawing back a bowstring, the greater the tension the bow puts on the string <S> the harder it is to pull the string. <S> A bicycle chain tensioned between sprocket and chainring is like a bowstring tensioned between the limbs of the bow, although obviously a bow string is deflected far more compared to it's length than a bicycle chain when changing gear. <S> So, a chain under greater tension does resist a gear change more than under less tension. <S> Modern chain, sprocket and chainring design have enabled successful gear changes under more power, but more pedaling force does still produce more difficult or noisy changes,
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Applying greater pedaling force does put the chain under greater tension - that's how the pedaling force is transmitted to the rear sprocket and hence to the rear wheel.
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Recommendations on how to make grips more comfortable? I find that on longer rides on my Trek FX3 that my palms (particularly my right palm) go numb from the pressure I am exerting on them. I appreciate that part of this is related to my posture and the need to strengthen my core muscles. Was wondering if there are any suggestions or recommendations on what I can do to make things a bit more comfortable? I have tried a pair of gel padded gloves but this does not seem to make any difference. Update Below is an image of grips: This weekend I paid more attention to when my palm went numb and it is definitely towards bottom outer half where the numbness starts. Basically where my palm rests on the "Satellite" section of the grip. Makes me wonder if I should try to adjust the angle which the Satellite sits. This will potentially stop my wrists from bending upwards and encourage more even distribution of weight on the palms. Update 2 After adjusting the saddle height/position and tilting the grips downwards to about a 45 degree angle I have noticed a huge improvement and my hands do not go numb anymore. <Q> I really think this is a fit issue (e.g., changing the bar height and/or reach, how you hold the bar) rather than finding softer grips or padded gloves. <S> Numbness should be taken seriously (as it can lead to permanent damage if left unattended). <S> Padding tends to help deal with issues associated with high frequency vibrations, rather than too much pressure that can result from poor fit. <S> With soft padding if there is too much pressure this just tends to force the padding further into soft tissues, which can exacerbate the numbness. <S> Ideally, with the proper fit your hands should only lightly touch the handle bars, which should make numbness rare. <S> Excess pressure suggests compensation from incorrect fit. <A> +, to allow you to change grip position <S> move your saddle further forward on its rails, to take some of the weight off your hands <A> You have flat bars, so your hand positions are limited. <S> Simply moving your hands a bit now and again will help. <S> Try rotating at the wrists a little, so pressure moves from your thumb ball to the outside and vise versa. <S> Decreasing the overall pressure on your hands is going to help. <S> Try pressing a bit harder on the pedals to take some weight off your hands. <S> Or raise the bars <S> so its not so far away. <S> If the road is quiet and smooth you can move your hands away from the brake levers too, for some relief. <S> Try cupping the very end of the bars as though you were going to crush them into the stem like a can. <S> You can also hold the bars right on top of the brake lever mounts (ie 50mm inboard from the normal position) or even further in, if there's some exposed bar. <S> Sometimes I put one hand behind my back for 30 seconds - this also gives the back a chance to relax. <S> More expensive changes could include barends or barmids, or aerobars (not completely silly) <S> You can also thicken your grips with extra layers, but this only goes so far before its cumbersome. <S> Try more gloves, and don't assume that more expensive are better. <S> The best gloves I've had were $4 chinese cheapies, and they outlast spendy $100 gloves. <A> I've had the same problem and the solution is to try to keep the forearm, wrist and top of hand in line. <S> Bending the wrist causes the numbness for me. <S> It is also helpful to keep your elbows slightly bent.
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If you're able, riding hands-free for a short distance can give relief, even if the hands are still hovering over the bars. You could try: adding some bar ends, or ergonomic grips like Ergon GP2
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Experience biking with child trailer during winter? What's your experience biking with child trailer during winter in the city? I live in Cracow, Poland. Recent winters were almost snow-less, but it's <0°C cold and slippery anyway. I am used to biking alone but never hauled 60kg behind me on a slippery road. Here are few things I am interested in: Tires on bike and trailer. I have Croozer 2 seater with whatever funky tires it came with. My bike is a folding electric city bike with nice Schwalbe Big Apple 20" tires. Mud/dirt. My Croozer came without any fenders. It get's dirty even during summer. Kids' clothes. It was 15°C recently and I closed the translucent "window" in the front of the trailer. When I put my hand inside after few minutes of biking it was really nice inside. Boys confirmed but they have a history of lying. (bonus) Electric 20" wheel in the back. This will be interesting :) Updated with bike details. It’s chinesium bike branded EcoBike in Poland. They probably sell under a different brand in other countries. <Q> I strongly suggest you put a studded tyre on the bike (ideally 2, but certainly the back in your case). <S> I run Schwalbe winters for occasional icy patches (overkill round here, except when they aren't). <S> This will be important for stopping as well as going. <S> Spinning the back wheel with a trailer is no fun. <S> The trailer tyres don't matter nearly so much. <S> They don't really need traction (though side-slipping isn't good). <S> You can get marathon winter tyres in 20×1.6" which will fit both your bike and your trailer. <S> The trailer will get cold inside in sub-zero temperatures. <S> But it will do a good job of keeping the wind off, so <S> your kids should be fine wrapped up warm. <S> Makes sure the to start with short journeys, as you won't be able to hear the kids easily (especially if you fit studded tyres) <S> and you want to know before too long if they get cold. <S> I know on a rear seat even above 0°C kids can get quite cold despite gloves and warm clothes, but that's only sheltered by my body. <S> Some form of hat or even a (thin) balaclava under their helmets would be a good idea. <S> Lining the seat with a blanket you can tuck round them might also be good if you've got room. <S> Visibility is important, including visual signs of the width of the trailer. <S> Drivers need all the help they can get to see your trailer in dirty, dark conditions. <S> I've got 2 of those plus a big steady rear light, as well as extra reflectors and lights on the wheels. <S> And that's just on the trailer. <S> Bikes and accessories get dirty in winter. <S> Mudguards won't help much on somethign so low to the ground, and every trailer is different when it comes to fitting accessories (as I found when fitting parking brakes to mine). <S> Folding makes accessories really tricky. <S> Overall you'd almost certainly have to make mudguard brackets of some sort, and remove them for folding. <A> Sounds like fun - I'd start by riding on quiet roads, and I'd fit studded tyres to all four wheels. <S> You can swap back to non-studded come summer. <S> Look if your ebike function has a limiter function. <S> You don't want full power else wheel slip. <S> My trailer always gets a skunk stripe on the front, from the rooster tail of the rear wheel. <S> BUT its got a "full" mudguard. <S> If you want to avoid throwing mud and roadwater at your kid's faces, look for a rear mudguard that goes a long way around the wheel, and hang a leather dangler/mudflap on the end. <S> These are more often used on the front wheel, but when towing will keep the trailer cleaner. <S> Comms <S> - I have a bunch of handheld radios, and use them for all sorts of weird things (eg dog training) <S> The inside one may work with Vox mode (transmit on voice) so you can hear their chatter :) <S> If the trailer does come around, you need room to stop braking and apply pedal power to get back in line, which needs road room. <S> Brake early when you need to stop. <S> If this doesn't help your braking you need to make the trailer brake the bike through the hitch, using some kind of brake on the trailer's wheels. <S> If you get a lot of snow, then you could fit skis. <S> Either change both the trailer's wheels and the bike's front wheel for short skis or somehow strap skis to the bottom of the wheel and let the length of ski prevent rotation. <S> For drive, fit a chain to the bike's rear wheel. <S> This would be a significant amount of work and only useful on snow/ice. <A> If you are going to ride main streets, you should not worry about the tires. <S> At least in Warsaw most streets are salted such strongly, that they are white from salt, dry and clean. <S> -10 is not a problem for "summer" bicycle tire on dry road. <S> Be careful during thaw. <S> Give up commuting with trailer when bicycle paths are covered with thin ice surface. <S> Make sure, that trailer hook is safe in every possible fall over scenario of your bicycle (turns, etc.) <S> and it will not pull the trailer and make it fall over also. <S> Keep in mind, that your pedaling helps you keep warm. <S> Your sons should be dressed even warmer than for winter walk. <S> Try work out some mini-excercises for them to make their muscles work, but will not affect trailer stability.
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Most important will be braking - your method may need to change, and if that's not enough you may need to fit your trailer with a brake. But if there are bicycle paths, even along those neatly cleaned streets, keep in mind that it may be icy and slippery the whole winter. Brake 80% with the rear brake, and only in a straight line else trailer will want to come around you. A rear mudguard on the bike would be a very good idea though, and one with a low, soft mudflap on the bottom. It would be hard to talk to the load when riding, so you could hook a radio inside for them and one on your collar. Little blinking LEDs as wide as possible on the trailer frame show up well.
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What kind of chain to buy for internal gears? What kind of chain should I buy if my gears are internal in a drum? I have seven gears but should I buy a one speed chain? What would happen if I would use a seven speed chain? <Q> The chain you need is 1/8 inch chain, usually sold as singlespeed chain. <S> A derailleur chain, which are sold as multi-speed chains, is narrower and the cogs may be too thick to fit. <S> EDIT: <S> As said in the other answers, some singlespeed and internal gear hubs have narrower cogs and can use the 3/32 inch chain. <S> An 1/8 inch chain may be slightly noisier with these cogs, but works. <A> To answer your question, if you used a 7 speed chain it will do one of two things 1) <S> It will either work perfectly (if the bike has "normal" thinner teeth on the chainring and cog) then its 3/32" chain. <S> 2) <S> or it won't sit on the teeth properly and will ride high, plus it might wedge onto the teeth and not come off when its supposed to. <S> This would be "Chain Suck" and would make for very bad riding. <S> In this case you require wider 1/8 <S> " chain Note: 1/8 <S> " is "wider" than 3/32". <S> 1/8 is the same as 4/32 and is therefore 25% more, or 33% additional space between the inner plates. <S> So you need the right chain. <S> Consider checking with a caliper, or take the old chain to your LBS and ask for one of those please. <A> You need a chain that is specifically a single-speed chain, not a multi gear derailleur chain. <S> However some single speed or IGH bikes use a narrower 3⁄32 inch (2.4 mm) single-speed chain, which is the same as derailleur chains. <S> To determine what you have currently, measure the distance between the inner plates of your current chain.
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For an internal gear hub (IGH) bike you probably need a 1⁄8 inch (3.2 mm) single-speed chain.
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How do I thread rear derailleur cable through this adjuster? this is a Lemond Zurich from around 1999 that I'm converting to 10 speed in rear. I can't get the cable to thread past this metal part that seems to be a fine adjustment for rear derailleur. I can't pull it apart. There is a spring mechanism between the part attached to bike frame and the rotating adjustment. Any experience with this? Ideas?Thanks,Bob <Q> They don't pull apart; the idea is that you're getting the couple mm of adjustment range you actually need, and the upside is it's an attempt at the easiest possible design to adjust on the fly while riding. <S> If there's something physically blocking the hole for the cable, you could presumably clear it by poking a pin or needle through. <S> Make sure the cable isn't actually getting stuck at the end of the housing though, either by the ferrule or by the end not being prepped properly. <A> The shifter cable come in two parts, the cable housing (outer) and the metal cable (inner) <S> that slides inside the cable housing. <S> The adjuster on the down tube acts as a "cable stop." <S> It stops the cable housing (outer) from passing through, but has a small hole to allow the inner metal cable to pass through and continue to the rear derailleur, where it enacts shifts. <S> The adjuster is threaded so that screwing it in it out changes the effective cable housing length, which in turn changes the tension of the inner metal cable allowing fine tuning of index shifting. <S> If you are able to pass the inner metal cable through, then everything is working as it should. <S> In no way should the black cable housing pass through. <S> If you cannot pass the inner metal cable though look for blockages (as suggested in other answers) or replace the downtube adjuster (they are inexpensive). <A> Thanks, everyone, for your answers. <S> I ended up pulling the whole adjuster and housing, which is inseparable from the adjuster, off of the down tube. <S> Eventually the tip of the cable found its way across whatever ledge was holding it up. <S> I didn't start this way because I couldn't get the adjust off of the down tube. <S> Having decided that this was my last resort, I whacked if off with a hammer.
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Being able to spin the adjuster and housing around the cable enabled me to pass the cable through (spinning the cable within the housing, when it is attached to the bike, is very difficult).
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Threading Shimano chain, over or under lug? I have an MTB with Shimano Deore/SLX components. I just replaced the chain. Should the chain go over the lug as I have it in the picture? <Q> Shimano seems to keep a lot of their documentation online , you can find your specific manual there. <S> For example, the site gives this picture for DEORE XT RD-M8000 derailleur. <S> Essentially, the chain needs to follow the shortest path between the two jockey wheels. <S> When installed properly, the chain won't touch the plate at all. <S> If it does you've routed it incorrectly. <S> But it appears from your pictures that it's routed incorrectly, the chain appears to be held off of the upper (lower in the photo) <S> jockey wheel more than I'd expect. <A> It's difficult to make out in this picture, but I believe the keeper bar on the cage should be forward of the chain. <S> If it drags, it's threaded wrong. <A> (See diagram) <S> It doesn’t matter that the bike is upside down, the chain is clearly on the wrong side of the plate.
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The way to determine whether the chain is threaded correctly is to see whether it drags on the keeper bar when it moves. The pictures definitely show a chain that is routed incorrectly on the wrong side of the derailment prevention plate.
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Installing a Bottle Cage without Mounting Screws/Threads I have a Next PX 6.0 mountain bike that I bought at Walmart a few years ago. It did not come with pre-installed mounting screws and/or threads for a bottle cage. The frame has large, strangely shaped tubes (oval-ish is perhaps the best way to put it), so many attachments that come with bottle cages also don't work as they are not big enough to wrap around the entire tube. My current configuration is with cable ties, but they keep breaking. It might be hard to tell, but the bottle cage is currently only attached by one cable tie, as the other two have snapped off. (The bike is hanging from the ceiling, which is why the orientation might look off.) Are there any options out there for a more permanent installation of a bottle cage? [EDIT/UPDATE: I gave this bike away when I graduated from college last year, which was before I got around to attempting any of the solutions offered here. If you're in a situation like I was, I'd say that the answers/comments that I was given should help you figure out how to the solve the problem.] <Q> Hose clamps are what (used to?) <S> attach a car's radiator hose to the radiator, if you've seen that. <S> If you have an old inner tube, you can slice that into strips to pad between the clamps and the frame so the paint doesn't get scratched. <A> Here are a few that I found while looking. <S> easy <S> if you know what to look for. <S> Will depend on what you want and need <A> I've used rivnuts to create mounts for bottle holders. <S> It requires you drilling into your frame and then tightening up the rivet nut, but once you have done that you would have effectively the same mounts that are present on bikes with the cage mounts pre-installed. <S> You would probably want M5 size rivnuts for compatibility with other bottle cage/fender bolt thread sizing. <S> Beware <S> This may compromise the strength of your frame. <S> Don't do this on carbon fibre or thin walled metal frames. <A> The answer of @compton brought me an idea - hose clamp but nicer - hose wire binding, like this: With some pieces of inner tube it will not damage the paint job and with some isolation tape it will be almost invisible. <S> The reasonable place for the knot is the underside of the frame so not disturbing anyhow. <S> Here is how to use one (DIY): <S> And here is how to make one:
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The approach I've seen is to use hose clamps to hold a bottle cage to the frame.
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How to service a Shimano TZ rear mech? I'm trying to swap out the top jockey wheel on a rear shifter mechanism. The bottom jockey wheel simply unbolted as expected but the top one seems to share a shaft with the main spring rather than having its own bolt. I can twist one of the cage plates a complete turn but it doesn't unthread anything. I can see a steel nubbin through a small slot, but its not shaped like a bolt head. Is this Unserviceable? <Q> These units are simply not meant to be serviced. <S> The end of the bolt looks stamped like a rivet anyhow. <S> It may be a bit short as an answer <S> but it's the (bitter) reality. <A> I cleaned my Shimano Tourney TZ today and i had the same problem (that's why i'm here). <S> I cleaned the bottom wheel and it was clogged with dirt and hairs .I <S> cleaned the top wheel the best i could because i can't remove it. <S> It now moves good enough without having to struggle and breaking the derailleur. <S> This answer confirms that the top jockey wheel is not removable in another Tourney rear derailleur. <A> Removing the top jockey wheel is simple. <S> Because the derailleur is budget the shaft for the top jockey wheel is riveted. <S> The photo also shows that there is a screwhead at the top. <S> It will be necessary to remove this by first taking off the plastic cover, then cutting off the screw head. <S> This allows the shaft to be removed. <S> This shaft is then replaced with a standard bolt and nut on the outside, having serviced the jockey wheel. <S> There is rarely a component that is not serviceable. <S> A bolt cost a whole lot less than a replacement derailleur.
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Manufacturers are relying on you not being able to work it out, or as in this case replace a riveted shaft with a standard bolt.
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What GT bike is this? I am thinking of buying this e-bike off of Craigslist but I am having difficulty figuring out if it an actual e-bike or a regular bike that has been converted. I wiki'd the list of GT hardtails and Google Images didn't show me anything that popped out. What we know: Hardtail Mountainbike The make is GT The Tires are Bontrager, possibly XR1 The guy isnt exactly answering my questions in complete English sentences. <Q> The brakes are cantilevers which would be 90s at best. <S> The tyres will have been replaced at some time, so brand means nothing to the bike's model <S> Batteries tend to be expensive. <A> Its a GT BMX Cruiser - the 24 inch - it looks like a 1999 model. <S> Cruisers are for BMX riders who are too old to be riding BMX :~) <A> Very definitely a conversion: motor in front wheel, strap-on battery pack. <S> Looks more like a BMX than a MTB. <S> Frame looks small.
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The whole bike looks like an overgrown BMX with a derailleur and rider bars with a reinforcement strut. Doesn't look anything special - theres a one-piece crank, indicates a cheap low-grade bike. The whole front wheel looks like its been swapped out for one of those hilltopper electric kits, which are not bad for a simple-fit kit.
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What is the foam tube on the top of bmx frame for? What is the foam tube found on some bmx bikes for? Here's an example: Besides for advertising, I'm guessing its there to save biker's legs when doing tricks, but I could be wrong, because I've seen most bmx bikes without it. What exactly is it for? <Q> Fine print: <S> More accurately, it’s to assuage the worries of the parents that are buying the BMX for their young male child that they might not have grandchildren. <S> Actually efficacy for such purpose is under debate. <A> It's to give the illusion of safety. <A> It's call TOP TUBE FRAME PAD or TOP TUBE PAD . <S> These were first seen on BMX bikes back in the 1980s, and did about as much good than as today. <S> A thin foam cylinder wrapped around the top-tube does little to protect the family jewels from a whack, but it does at least protect the knees from a knock when you bail on a 360º endo. <S> For a fixie, though, it is nothing more than posing — if the riders were that worried about safety, they’d buy a top tube pad. <S> price around $10-$30 <S> (Not exactly). <S> Thanks!- <S> Tim <A> For everyone who laughs of that foam tube: it's not a joke! <S> And you've seen most bmx bikes without because nowadays it's cool not to have as little parts as you can on the bike. <S> Some of riders (flatland bmx) still rides with ( often custom made ) stem pad like this:
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It's to ensure that young boys who ride BMX bikes will be able to have children when they grow up. It's exactly to save biker's legs as you guessed - for flatland bmx.
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How to fix an old bike I found? I'm new here and have a few questions if that's OK. I have been wanting to get a bike to ride around the beach town I'm close to so I mentioned it to my husband he asked what I wanted and I said we could just pick one up at a thrift store and if it needed a few things we could fix it up. Fast forward one week I was driving to the gas station at night and spotted a bike on the curb for trash pick up .You're gonna laugh but I thought well that's not in too bad of shape I would have bought that at a thrift store and I grabbed it and wrestled into my truck. I knew something was up when I had to fight it so hard that sucker was heavy (I'm five foot tall ). I expected a Walmart beach cruiser considering where I live and this was way heavier than that. I got it home and saw it was a JC Higgins bike. I haven't been able to find too much on what model it is so you have any ideas? The tires hold air which shocked me to death lol and I have cleaned it up somewhat, things seem a little loose, there is something up with the seat it doesn't feel like it's on right so I'll have to figure that out but it's in pretty good shape considering its age and fate as trash. Do you all have any advice to fix it up? Here's a picture lease excuse he mess we just had a tree come through the roof during Irma and everything is moved and jumbled around lol. <Q> If you don't want to spend any money, just take it slowly at first to ensure that the brakes and steering are working properly. <S> Ensure that the wheels spin freely and don't rub on anything. <S> It's ok if they wobble a bit on such an old bike, but if there is excessive wheel wobble you might want to have a professional look at it. <S> Looks like a single speed with a coaster brake <S> so there really isn't much to go wrong or adjust <S> but you might be best off having a professional take a look at it and making sure things are in working order. <A> In regards to the model, i can't post an image in comments so here is one to compare. <S> The Blue bike in the front is a 1960 JC Higgins flatliner. <S> Looks quite similar. <A> First thing to do is check everything's sound. <S> Watch a YouTube video on a safety check, go <S> round checking bolts are not only tight but that they are actually there. <S> Remember that if you got it for free it can be a good opportunity to learn bike maintenance and if you mess something up while fixing it you're no worse off, ask here <S> abs remember that YouTube is your friend. <S> I find RJ The Bike Guy particularly helpful if you're looking on YouTube.
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Alternatively, you can take it in to your local bike shop for a tune up and safety check. Try twisting the bars while holding the front wheel between your legs to make sure the bars don't turn with a decent amount of force.
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Conical head tube: does it really make huge difference? I am looking forward to getting a new mountain bike and in various reviews sites they are really focused on if a bike have conical head tube or not. In many cases it is the first thing listed as pro (or cont in case the bike don´t have it). It suppose to make the handling easier. But I don´t really see how that works. It is just another commercial trick or does is really affect the handling a lot ? <Q> Assume we have a tapered headset with 1.5" lower bearing and a straight 1 1/8" headset. <S> Let's compare two nearest thrust ball bearings from the manufacturer's spec (SKF ): 30x47x11 (dxDxH) and 40x60x13. <S> For 30mm bearing the fatigue load limit Pu=1.6 kN, for 40mm (the nearest to 1,5") <S> Pu=2.32 kN. <S> So the tapered headset can carry more weight or it will work much longer in the same conditions as straight 1 1/8" headset. <S> Additionally, the bigger lower part of headtube allows to increase the downtube diameter and make more stiff front-end. <S> The stiffer front-end gives more precise steering and increases the pedaling efficiency as well. <A> With a suspended mountain bike, obviously this is unnecessary and probably makes the suspension dynamics harder to dial in. <S> And increasing a tube's diameter is a better way to stiffen the tube than increasing its wall thickness. <A> Its an incremental improvement over a straight steerer. <S> A great bike from 2010 with a straight steerer will still outperform an average bike from 2017, and a tapered head tube is just one of 1000 small incremental improvements. <S> Today you cannot buy an average let alone a great bike with a straight steerer, so <S> a starting point for a quality check is if its got a straight steerer, its probably a BSO. <S> However, you need to consider far more than this one item to know if the bike is any good. <A> You mean a so-called tapered headtube probably? <S> Should be stronger in theory because there's more material on the lower part. <S> Geometry-wise it shouldn't affect handling as all measuerements stay the same (at least, I assume downtube length gets adjusted so all angles stay the same). <S> In theory it might be somewhat stiffer; that seems to be where most of the debate revolves around. <S> But I'd love to see actual measurements and blind A/B testing on that. <S> Let alone it makes for a true improvement when riding. <S> As usual: maybe if you are a pro and you can feel the smallest detail you could notice a difference. <S> (apart from that: not all forks are equally stiff anyway <S> and I don't think there was ever a huge debate in finding the stiffest one out there, so <S> it's a bit funny now that suddenly would matter a lot).
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Forks flex mainly at the lower head-tube bearing race (this is true even with traditional road forks that are curved to rake them), so increasing the diameter of the steerer tube at that point will stiffen it. With some bikes, you may actually want that flex, as it will dampen some vibration.
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Does having bigger wheels mean less effort pedaling? Assuming that we are using a fixed-gear bicycle and width of the wheels are the same, I wondered, does having bigger wheels mean I need to less effort to get from point A to point B in an urban setting? I'm thinking based on the formula for circumference: Where r is the radius of a bike wheel. Additionally when looking at this gif for a vertical visualization of circumference: It appears that having bigger wheels will get you from point A to point B in an urban setting with less rotations by the wheel, but does that also mean I need to work less to get there? What about uphill? Does having bigger wheels help/hurt biking uphill? <Q> Assuming a completely smooth road and neglecting the weight of the wheels, it makes no difference: you still need to do the same amount of work. <S> Essentially, larger wheels give you a higher gear ratio, so doubling the diameter of the wheels would mean you'd only need to turn them half as many times, so you'd only need to turn the pedals half as many times, but you need to press twice as hard on them. <S> If you need to lift 100kg of wood, it's easier to lift 10kg at a time, even though the total work done is the same as when you lift the whole lot at once. <S> Similarly, you'll be more physiologically efficent (and comfortable!) <S> pedalling with certain ranges of cadence and force. <S> Bigger wheels roll over bumps better. <S> As an easy thought experiment, consider a pit whose width is equal to the diameter of your wheel. <S> Obviously, the wheel will fall right into the pit. <S> But if you consider a wheel with twice that diameter, it will only drop a little way into the pit as it bridges over it. <S> In practice, though, there aren't a whole lot of wheel sizes to choose from. <S> Either you get a folding bike with small wheels, or you get a non-folding bike with wheels about 62cm/29in in diameter (or about 56cm/26in for mountain bikes). <A> Work is force times distance. <S> A larger wheel doesn't spin as much, but instead you have to deliver more force to turn it. <S> There is no escaping conservation of energy. <S> Additionally, I know you said fixed gear, but keep in mind that a multi-speed setup essentially does the same thing as you're hypothesizing about, but instead of changing wheel size it alters the torque-velocity relationship between the wheel and crank. <A> Wheel size is only part of the equation which connect pedal cadence with road distance. <S> Gears can change this ratio (almost) as well. <S> Even in a fixie you can get a lower or higher gear by changing the sprockets, thereby making the bike more suitable for flat or hilly terrains. <S> It can be just difficult (even impossible) to pedal very fast or very slow because of human limitations. <S> Gears ratios only allows one to keep the cadence where the human body can work better. <S> Given you set the preferred gearing, then the wheel size will only affect comfort (bigger wheels can go over road irregularities in a straighter path) and weight <S> (bigger wheels are somewhat heavier). <A> No it depends on which gear your fixed gear is. <S> Big wheels with a (fixed) low gear is similar to small wheels with a (fixed) high gear. <S> The (fixed) "gear" is the ratio of the number of cogs on the front to the number of cogs on the back (which, I guess, may vary from bike to bike). <S> Also I'd expect big wheels make it harder, not easier. <S> Wheels an inch high are easy to turn (but don't go very far or very fast). <S> Conversely, wheels a mile high would require a lot of effort to turn. <A> Maybe it has something to do with momentum. <S> Imagine the wheels like a fly wheel in a car. <S> The larger the wheel, the more momentum it has, so <S> maybe once you get the large wheel turning, it is easier to keep it going at high speed.
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If you decide that you cannot modify the sprockets of a fixie, then the wheel size (which is actually much harder to change than the sprockets) will affect the cadence for a given speed. Regarding work: at any pedal-to-road ratio the physical work is exactly the same. But, in reality, there are limits to what you can do.
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How to install flat mount road disc brake calipers on IS mount bike? I have custom MTB frame and I bought a pair of Shimano Hydraulic road shifters.They have on Shimano BR-RS505 Road Hydraulic Brake Calipers Flat Mount when instead my frame takes standard IS 51 mount (+adapter of course for it). What kind of adapter should I use?I have noticed that this kind of calipers use a front adapter mount and it might work on the back too... Thanks for your help! <Q> As of now there is no commercial product you can buy to make this possible. <S> An adapter that did this would be awkward to design because the flat mount caliper, in its native spatial position relative to the rotor and stay/blade, is trying to occupy some of the same space as the IS tabs. <S> I believe it's physically possible <S> but it would have to resort to being bulky and positioning the caliper quite far away along the rotor from where the tabs sit, which is a very negative design trade-off. <S> It may even raise questions about how much leverage the tabs or mounting bolts can handle. <A> I am not sure if I could build an adapter to use flat mount calipers on post mount frames, but this would mean putting the caliper farther from the rotor, affecting the positioning of it. <S> There might be as well another problem, that the natural curve of the rotor would not fit on a flat mount caliper used as post mount. <S> I hope this is useful (for somebody) and please let me know if you have any other question. <S> Paolo <A> A.S.Solutions <S> makes a post mount to flat mount adapter for 140mm rotor. <A> AS Solutions in Canada now sell an adapter for IS directly to flat mount, with caveats. <S> https://www.assolutions.ca/shop/adapters/flat-mount-adapter-for-is-frame/
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Just an update on this topic:I have now checked what is available on the market and realised (as we have discussed previously here) that the easiest way to achieve my goal is changing the calipers to post mount.
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Ghetto Tubeless w/ Gorilla Tape on a BMX Bike or Dirt Jumper - Good Idea? Why or why wouldn't you go tubeless on a 20" BMX or DJ bike? Got a lot of pinch flats recently and was look for a better solution than having to buy a tube every day/ I was considering doing the gorilla tape method on my 20" single wall BMX... is this a bad idea? From my research, I've found: Tubeless Cons Sidewall takes a beating in BMX / DJ causing the tires to burp (more dangerous, could cause crash) Sometimes you want higher tire pressure (BMX street riding) and tubeless is not good for high pressures Tubeless Pros Lighter (by a little) Easier flat maintenance Better against thorns than a tube Is able to run lower tire pressure for more grip Cheaper in the long run (tubes are ~$10 a pop) I mostly dirt jump with my BMX, so I see more pros than cons. Any experience or thoughts? <Q> Your pros list for tubeless is highly debatable. <S> Tubeless are less likely to puncture and more likely to self seal if they do puncture, so you have to fix less often, but.... <S> Fixing a tubeless puncture that did not self seal is a workshop job, not a field job. <S> MTBers running tubeless carry spare tubes so they can get home if they puncture. <S> Cheaper in the long right - very doubtful. <S> Tubeless require a slime top up every 3 - 6 months. <S> Tubes are a one off lifetime cost. <S> As is you cons list. <S> Maintenance - 3-6 monthly slime topup vs an occasional squirt of air into a tube. <S> IMHO tubeless for a DJ or street BMX makes little sense as the single big advantage - running lower pressures to get more grip cannot be utilized. <A> Better off using tubes and making sure they line the rim properly / are seated properly and you have inflated them enough. <S> For SS / DJ you need air. <S> Like 60PSI or more not uncommon to avoid pinch flats. <S> Also it helps to learn how to not smash curbs and things will full velocity. <A> I've run tubeless "ghetto" style before. <S> Meaning on rims and tires not specifically designed for tubeless. <S> It's not that hard, other than getting the beat to seat, but that's a pain anywhere. <S> I used STAN's rim strips that have the valves built in, and a ring of gorilla tape. <S> I would always have wet beads, but not enough to drip out. <S> It will function. <S> That said, like others have said, this isn't really solving the problem you want. <S> You're supposed to run high pressure for BMX and DJ stuff. <S> If you are having traction issues, maybe try better tires? <S> I don't know what's available for BMX size, but on a 26" DJ you could try pretty much anything. <S> I use Maxxis Holy Rollers on my DJ (again, a 26") and I get very good dirt traction. <S> One place I have had traction issues is in indoor skate parks, particularly when they haven't cleaned the ramps recently. <S> But lower pressure is exactly what you don't need in situations like that. <S> One think you could try is putting STANs sealant inside your regular tube. <S> It should sell seal punctures. <S> I don't know what effect this would have on anything. <S> But it sounds like the best bet here is better tires, "double thick 'DH' tubes, <S> if they have such a thing for 20", and high tire pressure. <S> If the harshness of high pressure is what's making you want to drop the pressure, gif a 26" mtb-type DJ bike for a spin.
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You would build up a lot of sealant between your tube and tire over time. Weight - much less a concern for DJ and BMX bikes. Cost - slime is not cheap. In reality, most riders could afford to loose 100 times more weight than the difference tubeless makes.
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Riding in single line Is it safest for a group of cyclists to ride in a single line? Is it required for cyclists to ride in a single line in a narrow bike lane, or can they pass on the left in open traffic? <Q> In general it depends on the road or trail, <S> how wide it is, <S> how straight or twisty, how visible the trail ahead is etc. <S> On a wide trail without tight turns and plenty of forward visibility riding two-abreast is fine. <S> On a narrower trail with tighter turns or less visibility, riders should ride single-file and stay on their side of the trail. <S> Common sense applies to overtaking, i.e., don't try to pass if you can't see far enough ahead. <S> There may be laws that apply to cyclists in different locations of course. <A> For example, suppose the road isn't wide enough that a car can safely pass a bike. <S> Conversely, if the road is wide enough to allow cars to safely overtake a single bicycle but not two bikes side by side, it's likely to be safer – and more polite! – to ride in single file. <A> I assume you're referring to a pace line, where riders take turns on the front. <S> You'd think a dual pace line is wider than a single paceline, but with a single there's almost always a rider drifting to the back, either on the left or the right. <S> So effectively they're the same width most of the time. <S> A dual paceline has two columns of riders, so blocks each other's view to some extent. <S> But a single line has a larger differential in speed between the column and the single, so its a higher relative passing speed.
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In this case, it may be better to ride two-abreast because that makes it impossible for cars to pass, whereas riding in single file might result in some cars trying to make unsafe passing manoeuvres. This depends very much on the situation, and on local law.
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Unable to get into a 'TT' position, is my bike fit wrong, or am I just fat? I've been road cycling since July 2017. I am an overweight guy, the cycling has helped shed some kilos but I'm not at my ideal weight yet, and most of my weight is stored in my belly. A month after getting my bike, I got a professional bike fit done, and it has made me very comfortable on my bike. However, when I go on group rides I see the more experienced riders always get into a TT position (forearms on handlebars) during long stretches of roads. I have tried to get into that position but its uncomfortable, and my peddling becomes extremely inefficient. My question, is this because i'm overweight and lack flexibility, and this will just come with time, or is my bike fit wrong? <Q> A bike fit is not intended to make any position you can adopt on your bike work. <S> You say you are 'very comfortable', presumably in the position you ride in most of the time, so the bike fit should be good. <S> If you have only been cycling regularly since the summer, starting from less than ideal physical condition, I would not be at all surprised that getting into a slammed position on the bike is going to feel pretty horrible. <S> The good news is that you can lose weight and improve strength and flexibility over time, and you will be find it easier to adopt a more aggressive position. <A> Even strong cyclists can have trouble with it. <S> This video (jump to about 4:25) shows how much trouble a guy who can ride at 300 W <S> (that's strong) can have holding a tuck for even a few minutes. <S> So what I'm saying is, don't stop working on it, but remember you've got lots of company. <A> I just went for a ride in the middle of the day. <S> Normally I wear cycling shorts under my regular trousers/pants with a leather belt. <S> However it was quite hot <S> so I simply put the critical things in my jersey pockets and did without the pants. <S> The difference was significant - on the drops my thighs touch my belly every pedal rotation. <S> Yes it was a lot cooler for riding <S> and I smashed a couple of PRs, but not sure if the inference between leg and stomach was less bad than the cooling <S> was helpful. <S> So, try wearing a belt while riding, and see if it helps or hinders.
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If the bike fitter did their job correctly, then would have set you up for your current level of flexibility, strength and desired riding style. Regardless of your weight, holding an aerodynamic position isn't easy: it requires some core strength and flexibility.
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Why do I keep getting cut looking flats? My flats are causing some deep confusion. In the last year I've replaced at least 12 inner tubes because I keep getting flats. They are not puncture or pinch flats, they look like cuts to the tube, sometimes small incisions sometimes long gashes. They're always the back tire on the side facing the hub and they're usually close to the valve. Tubes only last a couple of rides and it seems to be getting worse. I took the wheel to a shop recently hoping to gain some insight into the problem and the guy replaced the rim tape and put a new tube in and it went flat on the walk home. I tried a heavier duty 'hybrid' bike tube, and that only lasted one ride. What happens is I'll ride it once or a couple of times and either during the ride or more often at home later, after the bike has been sitting for some time, I'll hear a hissss and it's flat. When I examine the tube there's a hole that looks like a slice near the valve. Anyone have any clue what could be going on or what to do about it? I'm thoroughly confused.Could it be a poorly designed rim? I thought it had something to do with the rim being too narrow and that putting excessive pressure on the tube. Only thing is I can't figure out why it would pop when the bike is at rest. <Q> Is the cut always the same distance around the tube from the valve? <S> If so then you have something wrong in your rim. <S> Use the punctured tube to measure where the damage is coming from... that will give you at most two positions, one in front of the valve hole and one behind. <S> I think you'll find a cause in this very small sector of the rim. <S> BTW - had you patched your tubes rather than replacing them, the punctures might have been reduced by the extra thickness of the patch in that spot. <S> And if they punctured again though the patch, then you'd know straight away something's wrong there. <A> I could swear there's already an answered and highly upvoted post here that features this exact issue, but I can't find it. <S> This is a really infuriating and mysterious problem. <S> I've run into it a couple times. <S> It's hard to figure out and is an under-publicized issue. <S> The only bright side is the symptoms are always the same - repeat flats, always the same inexplicable cut/gash near the valve, rim side, no burrs, no irregularities, no protruding spokes, rim strip in good condition, replacing rim strip anyway doesn't help. <S> It happens due to this combination of factors: <S> Most of the inner tube is one single, supple layer of rubber that expands easily to fill whatever cavity it finds inside the tire. <S> The part that isn't quite like this is the reinforced area around the valve. <S> Some rims, from what I've seen ones with kind of a funky cross-section that narrows at the bottom more than usual, keep the reinforced area from being able to lay flat against the rim under pressure without introducing a stress riser into the tube rubber. <S> This is what causes it to burst, sometimes very quickly after inflation. <S> I've heard the notion that by tugging down on the valve aggressively as you inflate it, you might be able to mitigate the problem. <S> I'm highly dubious but it may be worth trying. <S> I've been able to fix it seemingly for good by layering pieces of rim tape and/or tube at the valve to build up the area there, essentially creating a more normal face for the valve to interface with. <S> A normal rim strip then goes on top of all that. <S> I believe I cut the valve hole on each of the layers first. <A> Sounds like a spoke is a little too long to me. <S> It could also be a bur of metal sticking up inside the rim. <S> Take the tire and the rim tape off the rim yourself and carefully run your finger around inside the rim. <S> Use care not to cut yourself. <S> If you find a sharp edge or spoke that is too long, well? <S> Sand it or file it or recruit someone to help you. <S> You may also want to consider just getting a new wheel rim. <S> They are not prohibitively expensive.
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Note that doing this on most rims could easily create problems with the tire bead not wanting to seat evenly near the valve, but from what I can tell this issue tends to come up on rims that are odd-shaped with deep well sections. In other words, it is not any of the usual causes of repeat flats from the rim side. I used electric tape to hold them in place and I layered several lengths of them to create a little bit of a taper effect to smooth the transition.
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What if I choose replacement tires narrower than my current tires? I have been looking for some tires I could buy but I couldn't find exact numbers (My current tires are 27.5 x 2.8) I found one which was 27.5 x 2.10 or should I get one which is 27.5 x 2.1 Both of them are the same price but I don't know which one to get, can you please tell me? <Q> 2.8 is bigger than 2.10. <S> When you run a bigger tire, you have to worry about the tire rubbing on the frame or fork. <S> Running smaller tires are usually simpler. <S> Narrow tire on wide rim could increase risk of damage from hazards. <S> See this page for details: http://www.sheldonbrown.com/tire-sizing.html <A> You have three basic concerns when thinking about changing tire width <S> Will different tires fit your rims? <S> If fitting wider tires, will they clear the frame and fork (and leave enough clearance for mud or debris if riding off road) <S> How will different width tires affect the ride and handling of the bike. <S> There are various resources for determining tire width / rim inner width compatibility, including the chart on the Sheldon Brown page linked to in other answers here. <S> Tire manufacturers should provide min and max rim widths for each tire model and size. <S> Presumably at 2.8" you have an MTB <S> so you need to think about the potential for reduced bump absorption and traction with narrower tires. <A> 2.8 is a fairly wide tire. <S> Mountain bike I assume. <S> Moving to a 2.1 tire is a big difference. <S> Here are some more questions to consider: <S> What terrain do you ride on? <S> (streets, trails, singletrack?) <S> Bead type (wire or folding?) <S> Tubeless tires (yes or no)? <S> Is there something you dislike about your current tires? <S> If riding on trails/singletrack, I would stick with the wider tire, as you can use lower pressures for more grip without fear of pinch flat.
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Tire sizes have to be appropriate for the rim width; wide tire on narrow rim could have some control issues/sloppiness (and if you had rim brakes, that could also cause some rubbing). Whether you can, or want to drop to a 2.1" from a 2.8" tire in terms of ride and handling depends on what type of bike you have and what riding you are doing.
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Use of winter (studded) tires on only one wheel? Does anyone have any thoughts on use of winter (studded) tires, such as the Schwalbe Marathon Winter tires, on only the front or rear wheel (and with a standard tire on the other wheel)? <Q> One winter tire is better than none if you're going to be riding in snowy conditions, so go ahead and throw it on. <S> If you do end up running only one tire, you'll probably want it on the front wheel so you don't lose traction while cornering and so that you can maximize braking performance. <A> I have found studs on the front and a regular tire on the back gets the best trade-off of speed and stability. <S> Two studded tires is just way too slow. <S> Sometimes rear traction isn't great and your rear slips and sldes, but not often and when it does, you rarely wipe out. <A> Studded tires are of the greatest value on ice, and if you are riding on ice you want as good as traction as possible, especially on the front wheel. <S> In patchy ice you can coast through at speed with no traction and not crash as long as you are not trying to steer, brake or accelerate. <S> With a studded front that changes to lightly steering may not result in a crash. <S> I also like studded tires on mixed ice and snow, but for heavy snow I like mudders. <S> A good knobby tire handles better in deep snow than studded does. <S> My general purpose tire choice is a tire with a smooth center ridge and big knobs that contact as I turn or sink. <S> I use such tires in every thing from 8" snow to rain and mud or dry roads. <S> They are not the best choice for ice but the local climate is not known for ice (beyond the occasional patch). <A> As I currently have exactly one schwalbe winter at home <S> I've been thinking about this myself. <S> I've come to the conclusion <S> it's a bad idea for me. <S> I'm mostly concerned about patches of sheet ice, and on those I want the front wheel to hold a line, but wouldn't trust it for much braking. <S> I wouldn't brake hard and would brake more than normal at the back, less at the front. <S> So I would want grip from the back tyre - it might fishtail if I get it wrong <S> but it would still slow me down. <A> I purchased my first set of Schwalbe Marathon Winter tyres after I destroyed the 28" back wheel of my Kalkhoff bike. <S> I hadn't realised that the temperature had been below zero (°C) <S> overnight <S> (it's rare enough in the west of Ireland). <S> As I leaned into a left turn I felt the rear wheel start to slide on ice. <S> It then hit a dry patch and I managed to right the bike and save myself but badly buckled the wheel. <S> I had to have the wheel rebuilt as it has an 8-speed Shimano hub. <S> I purchased the tyres for the next winter. <S> I found them quite reassuring but a bit noisy - like riding on fine gravel all the time. <S> The second set I purchased didn't seem to last very long. <S> The studs wore through the tyre and punctured the tube several times. <S> I felt as though there had been some deterioration in quality. <S> I would not recommend front tyre only.
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With a studded front, stability to avoid wiping out is there, especially in those obnoxious snowy ruts.
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Can you reattach an SRAM powerlock? An advert for their PC-1031 chain on chainreaction said the Powerlink Powerlock was one time use only; you couldn't attach the chain, detach it and then attach it again without a new Powerlock. I understand Powerlocks probably only guaranteed the first time, but in practical terms does it really work that way? Do chains usually snap if you try to reuse the Powerlock? <Q> For 9 speed or below, SRAM sells the Power link , which is a reusable way of opening and closing a chain. <S> You can open and close these a few times, at least for the life of a chain. <S> It is not designed to be opened and closed, and it is not suggested that you re-use it. <S> Do people re-use Powerlocks? <S> Sometimes. <S> Do they get away with it? <S> Fairly often. <S> Do they come apart? <S> Also reasonably often. <S> Would I recommend it? <S> Of course not <S> -- they're cheap, just buy a new one each time. <S> It's generally going to be worth the potential costs of dealing with chain failure when you're out riding. <S> If you want to use a quick link for a 10 speed+ chain thats able to be opened and closed repeatedly, try the KMC Missinglink for 10 speed chains or the Wipperman Connex link. <S> Both are designed to be reusable. <S> (*) <S> (*) <S> Officially, chain manufacturers don't recommend mixing brand X's chain closing mechanism with brand Y's chain when X!=Y, but people have generally found it safe to mix quick links between manufacturers. <S> So, with this in mind, I'd still recommend the KMC or Wipperman if you want to detach and reattach the chain repeatedly. <A> Do not reuse 10 or 11 speed quick links. <S> Doing so could result in a snapped chain. <S> This will potentially cause injury to yourself and/or others and it's not worth the risk. <A> I've had no problems with re-using them (on both mountain and road bikes). <S> Be aware though that unlike 7/8/9 speed SRAM powerlinks you can't remove the 10 speed ones by hand, you'll need pliers. <S> (You can get special chainlink pliers designed for the job which make it very easy.)
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For 10 speed and above, SRAM sells the Power lock , which is a one-time use way of closing a chain.
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Choosing frame size when still growing I am about to purchase a 2018 Kona Sutra touring bicycle but I need some advice on how to know which is the right size for me. My measurements are 174cm tall with a 79cm inseam. I was advised that a 52cm size frame was the right size but I am 18 years old and I still have the potential to grow. On a 54cm frame the top tube almost touches my crotch but I was told that if I were to grow anymore that a 54cm frame would be perfect and now I am left with the decision on which size to buy. <Q> I would go for the bike that fits well today. <S> You can allways increase the saddle height a bit should you grow a bit more. <S> A good fit is very important when it comes to your enjoyment of the bike. <A> The 2-20 years growth charts here includes predictions of adult height. <S> The boys chart shows that growth between 18 and 20 is less than 1cm (obviously this is averaged over a arge population, and delayed puberty would have a bigger effect, but that would be a different issue). <S> There are two ways given to predict final adult height. <S> One is percentile based (i.e. based on which line you;re on now) and the other is based on parental height (via the percentile you're likely to end up on). <S> Unless there's a big mismatch between the two, you don't need to worry about it. <S> Just don't get a bike that's on the small side. <A> As @Kristian said, best option is to choose bike size that fits you at the moment. <S> If you're afraid that your bike will become too small too fast <S> and you don't want to spend money on second new bike, <S> consider buying pre-owned bike now. <S> If you really want to buy oversized bicycle, make assumptions about your future height by taking into account <S> your (especially male) kin's height. <S> It could be burdened with non-negligible error. <A> I would go with the 54 on a touring bike. <S> I grew an inch between 18 and 22, and the clearances for Paineers are greater for the larger frame. <S> You might want your handlebars closer to your center if you get the bigger bike by asking for a shorter stem. <S> When you say “I was told” listen to the certified bike fitter. <S> If you’re buying the bike from a shop, they should give you a free fit. <S> You should have your seat fit for you as well.
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If you do grow, you can get a new bike in a couple of years, if you don't grow you're not stuck with a too large bike. Unless you're very unlucky or your growth has been delayed for some reason you should be within minor adjustments of your current height for the foreseeable future.
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For fitness's sake, is it better to ride with low cadence in high gear or higher cadence in medium gear? I've started riding to get fit and lose weight. As part of that, I set little challenges for myself, eg: "I'm going to ride these next two blocks as quickly as possible in the highest gear". I'd be pedaling slowly and strenuously but moving quickly. As I got more fit I would spend by far the greater part of my 20klm daily ride in the highest gear. However, someone at the bike shop where I get repairs mentioned I was doing it wrong - that I should be aiming for higher cadence and only use the top gears when going down hill. What's better solely for losing weight? <Q> In terms of losing weight immediately, the obvious answer is to use whatever gear combo allows you to produce the greatest energy output. <S> For most people this will likely be a hair lower than the "preferred" range of about 70-90 RPM -- maybe 50-60, and pedaling as hard as you can. <S> However, if you want to KEEP losing weight by getting on the bike again tomorrow (or even just later this afternoon) then you should avoid muscle and joint injury by running at a higher RPM (70-90) and not being quite so extreme in terms of putting out effort. <S> And one should consider doing "intervals" of alternating high effort and low effort (eg, 5 minutes high, 10 lower), as studies have shown that this produces both better weight loss and better muscle building. <A> All things being equal, aerobic exercise is probably best for losing weight (after all, the only way to lose weight is to breathe CO 2 out your nose). <S> If you use too high a gear, you might be less aerobic and more resistance training, which builds muscle mass. <S> Either way, at this point, it sounds like getting yourself moving in whatever way you like will be most effective. <A> Your cadence is not important for fitnes. <S> Your distance is. <S> tl;dr; <S> In terms of fitness losing/gaining weight is all about your energy balance . <S> You have calories you gain during the day minus calories you lose on different occasions(mostly physical exercising and walking, but variants are possible here). <S> That's what you get a day. <S> You also have some certain level of calories(call it X), you need just to keep on. <S> Changes in your weight depends on your consume rate relatively to X and on your lifestyle(your habits may affect your X, because of that some diets are more effective than others). <S> Move your body a certain distance by means of bicycle takes relatively same amount of energy with high and low gears(you may do physical counting to compare the difference, but you may also find more effective ways of spending your free time). <S> Your speed is important thou, cuz you put more energy into working against the wind that you don't feel, when your speed is slooow. <S> there was a plot of work against wind during bicycling <S> , i'd be glad if somebody post link in comments . <S> Your cadence affects does affect different stuff like consuming air efficiently or developing and strengthening your muscles as well as damaging your knees at too high effort for your level of bicycling. <S> But i assume, the main parameter you may need, if you prior target if fitness, is your ability to work regularly and get tired as less as possible, so <S> a good advice is to use both low-cadence and high-cadence riding to decrease the exhaustion caused to a certain parts of your body and divide it to as many parts as possible. <S> If you feel it's hard for you to ride with high cadence - ride with low cadence. <S> If it's hard for you to ride with low cadence - you've got me. <S> You target is kilometers, not the exhaustion. <S> You have to work hard to improve yourself, there are no easy ways, but you probably don't have to suffer . <A> Losing weight is a consequence of maintaining a net negative energy balance, i.e. metabolising more calories than you consume. <S> It's no more or less than this physiological fundamental. <S> The total energy you metabolise each day is a combination of your basal daily metabolic output plus whatever extra calories you metabolise through exercising and other activities. <S> If cycling then that's simply a function of the average power through the cranks (watts) multiplied by the duration you rode for (seconds) divided by an efficiency factor (approximately 0.21, since humans are not 100% efficient at converting fuel substrates into mechanical energy). <S> In order to metabolise more than you currently do, the trick is to ride harder for longer. <S> As for calorie intake, that's all about what and how much you eat and drink. <S> It's way easier to consume calories than it is to metabolise them, so keep that in mind when considering where the priority lies with weight management. <S> As a rule of thumb, think about training being mostly about improving your fitness (power output) while you eat in a manner to get lean. <S> With respect to what your bike shop said, there's not a lot of context to go on but <S> my view is if you are cycling, enjoying it and not harming yourself or anyone else, then who cares what gear you choose to ride? <S> Just have fun.
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However our ability to ride hard comes with some limitations on our ability to sustain the effort level for very long or to consistently repeat such effort, and so to increase the calories metabolised most people simply ride for longer durations. The gear you use on your bike is of little to no relevance.
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What are the brake housing stoppers on the end of the brake housing called (see pic) My brake cable snapped while riding my (80s road) bike one day so I replaced it. After replacing I noticed that the piece fixing the housing to the brake was missing so that when I pulled the brake lever the housing comes too and it doesn't move the brake. My questions: what is this piece called, and is it something I can buy separately, Is it something that comes with brake line housings, or is it part of the brake lever itself? <Q> They don't really have an agreed-upon name. <S> Probably the closest is "mushroom ferrule," which appears to be what Dia-Compe calls them. <S> They're not totally universally sized. <S> Different brake levers have slightly different bits that go there but do the same thing. <S> That said, the ones on the great majority of bikes with applicable levers are all the same size, which I believe is basically Dia-Compe and clones. <S> You can just buy the common size ones new. <S> In the US, J&B Importers (one of the largest parts wholesalers) has a house brand one they call a "Cable End Button" and <S> UBS has one they call "UNIV BRAKE CABLE ADAPTER. <S> " <S> There's also Dia-Compe part 94 , same thing. <S> Some shops will also have old levers around to cannibalize. <A> If you mean these things, they’re called cable ferrules — or more specifically, brake (cable) ferrules. <S> Some people also call them cable ends or cable caps. <S> They’re cheap. <S> Your local bike shop can give you a handful for a euro-dollar (or for free depending on how much you patronize them). <A> Looks like the component in question is part of the levers and might be a barrel adjuster. <S> BTW that style of lever units with the secondary levers accessible from the tops are known as 'suicide levers' around here. <A> I would call them cable ferrules , but that same name also applies to the round cylindrical brake and gear cables like <S> Your best bet might be to troll through ebay, or to search out classic bike parts resellers or breakers. <S> If you don't care about period look, then a set of more modern brifters could work for the brakes alone, and keep using your existing separate shifters. <S> These ones are part of the brake lever, and are generally hard to find separate. <S> Plus there's a lot of variation in diameters across brands. <S> These are intended to take the strain off the very end of the cable housing, and reduce the likelihood for the cable outer to bent sharply as it exits the top of the lever. <S> So they don't sit quite flat in the top of the brake housing. <S> Your last resort might be to mill something up from a block of aluminium. <S> I've made a gear cable endstop and <S> while it was many hours of fiddling, the result worked well for me. <S> Assumes a level of mechanical competence and access to a lathe and drill press, and inordinate amounts of time and dedication :)
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They're essentially part of the brake lever. You can just order any of them from an online reseller, or find a shop that has them.
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Are there any major outstanding recalls of bicycle parts? Sometimes bike companies don't get things right. Are there any major recalls people should know about? Where can people find information on recalls? There is one answer which has places to find information on recalls (for a given country). Other answers could be by part. (Moderators: I'd like this to be community wiki) <Q> Places to Find Information on Recalls and Safety Issues United States <S> Recalls.gov <S> To report safety issues, SaferProducts.gov <S> A convenient listing, Consumer Affairs <S> New Zealand <S> https://www.recalls.govt.nz/ <A> CPSC Recall Number 18-002. <S> Description: This recall involves the Avid SD7 bicycle mechanical rim brake. <S> There is a date code stamped on the back of the brake arm with the date format DDMMYY representing the day, month and year of manufacture. <S> The brakes were sold separately by SRAM and were also installed as original equipment on ElliptiGO model 11R elliptical cycles. <S> Remedy: <S> Consumers should immediately stop using the recalled brakes and contact SRAM to receive free replacement brakes and installation instructions. <S> Incidents <S> /Injuries: SRAM has received five reports of loose or detached rivets. <S> No injuries have been reported. <S> Sold At: Specialty bike stores nationwide and online at www.jenson.com and www.REI.com from June 2014 to May 2017 for about $40, and installed as original equipment on ElliptiGO model 11R elliptical cycles from October 2014 to May 2017 for about $3,500. <S> Importer(s <S> ): SRAM LLC, of Chicago, <S> Ill. Manufactured <S> In: Taiwan Units: About 7,000 <A> Quick Release http://bpsa.org/quick-release-recall/ <S> Certain front-wheel quick-release cam levers that are improperly adjusted or left open while riding can come in contact with the front-wheel disc brake rotor, also potentially causing the front wheel to come to a sudden stop or separate from the bicycle, posing a risk of injury to the rider. <S> Only applies if your bike has a disk brake, and a QR lever that could interfere with the disk in any open or closed position. <S> This could affect bikes from the 90s through to about 2015. <A> Manufacturers <S> This is a non-exhaustive list. <S> Brompton <S> https://www.brompton.com/About-Us/BB-Checker-Consumer <S> GT <S> http://www.gtbicycles.com/usa_en/recalls/ <S> Haro <S> https://www.harobikes.com/safety-recall <S> Schwinn International <S> http://www.schwinnbikes.com/int/support/recalls/ <S> Schwinn <S> USA <S> http://www.schwinnbikes.com/usa/support/recalls/ <S> Trek <S> https://www.trekbikes.com/us/en_US/company/legal_policies/safety_recalls/
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The US Consumer Product Safety Commission is the organization responsible for recalls and safety issues in the US. Brakes The Avid Single Digit 7's have been recalled :
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Bike travel bags, hard cases, and homemade bags I am regularly using airplanes for transportationbetween race destinations. In fact, travelling witha bike is always a very stressful situation. Usually, I amvery afraid when I have stopovers, because mostof the airport staff do not handle my bike bags politely. In line with this, when we arrive onfinal destination, bag is very dirty and someparts are even broken or damaged. Despite of manybags that I have already used, I am wondering ifthere is a possibility to create a bag at home. Has anyone experience with homemade bags? I am still looking for appropriate material. Woodseems to be very heavy, whilst cardboard boxes aretoo soft. What do you think? <Q> If you travel regularly, buy a decent, high quality hard shell or accept your bike will be damaged. <S> Depending on your travel and carriers, you will probably find a home made case will offer poorer protection and cost more in baggage charges due to it being heavier. <S> Its unlikely a home build case can be made light and strong compared to a commercial hard shell. <S> Also consider the cost of a damaged bike is may be far more than the cost of repairs. <S> If you bike is badly damaged going to your destination, your entire holiday could be ruined. <S> Travel insurance can help here as you would not need to be concerned about cost of repairs at destination (e.g. say you bend a derailleur and the only available replacement at the bike shop is Ultegra or XTR, insurance would cover the repair cost). <A> Packing things for travel or freight is a balancing act between convenience, protection, and weight. <S> A wooden case would be heavy, or thin enough to be light leads to less protection. <S> If you do make a case, look to making it layered with protection from sharp thing on the outside plus softer padding on the inside to absorb shock. <S> There are computer/server packing gear that involves filling a soft plastic tube with blowfoam and letting it expand around the item. <S> If you did it carefully, the bike/wheels should be able to pop out of the foam with minimal/no disturbance. <S> If your hard case was built like a big clamshell with clamps and it opened wide, that would be ideal. <A> While you want to take your own bike with you, have you looked into Bike Friday's foldable bikes that are the "same size" (= geometry) as a regular bike, but fold into a Samsonite suitcase?
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Even with the very best case, your bike could be damaged - either accept it as a cost of travel, or purchase travel insurance that covers the bike.
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Buying a DH frame to build an Enduro? First of all, I haven't set my budget yet but I want to build a full suspension MTB in the near future. I was thinking if it is a good idea to build an Enduro bike with a DH frame. I mean I know the suspension travel for DH is longer, so logically 'maybe' I can put an Enduro fork in there and effectively reducing the slack geometry (slightly) since the fork is slightly shorter (?), while setting/changing the rear suspension also shorter, also Enduro gearing, then boom I have an Enduro bike. Then when I want to do a more aggressive DH I can 'simply' change the fork and use longer suspension travel in the back and boom I have a DH machine. Initially I was thinking this but with Enduro frame instead, but it seems more doable with a DH frame as 'logically' you can use shorter suspension on a supposedly long suspension frame than the other way around. What do you think? is this a bad idea? <Q> If you are doing it because its fun and you want to play and learn about bike building, dive on in, but be prepared fro less than stunning results at higher than expected prices. <S> Unless you are a very skilled rider, and a skilled bike builder (not assembler) <S> I believe it's bordering on arrogant to think you can do better cheaper. <S> The other issue is the bike components them selves. <S> Would you rather have a $500 enduro fork and a $500 Down hill fork, or a single $1000 fork. <S> My money is the single $1000 fork will do both jobs better. <S> Same applies to wheels, gear sets..... <S> If you have done all that, and still feel the bike is the limit factor of your riding, you probably need two bikes. <A> Unless of course you want to make an enduro bike with 180mm front suspension, so its not enduro anymore! <S> If I wanted to build something nice and strong from the beginning, I would start with an enduro frame. <S> Both frame options can get any peripherials we want - fine! <S> As far as suspensios are concerned though, we need to bee ccautious, cause their size affects geometry. <S> Bigger suspensions <S> up to 20mm are acceptable to most frames and geometries. <S> I wouldn't personally risk go lower though. <S> DH bikes are made for 180-200mm and putting a 160mm enduro fork would mean bad behaviour from the frame and the fork in trails, bacuse geometry is ruined. <S> But an enduro frame upgraded from 160 to 180mm is not that terrible. <S> Actually is not terrible at all, its awesome and its predictable both by manufacturers and riders! <A> I'm 100% with you on this. <S> I have a 2007 Giant Reign X (6.7 inches, lighter version of the Glory) with Rockshox Totems (7 inches and 1 1/8 steerer), 11 speed, dropper post and ztr flow/hope tech enduro rims. <S> That frame is an excellent little piece of kit and is regarded as the DH's XC frame or the XC's DH frame. <S> I get out once a week and have been getting decent Strava positions on climbs against people on dedicated enduro bikes with my build. <S> I simply cannot afford a newer and more modern enduro bike, but am happy to forgo a little more weight for something to hit the DH etc sections a little harder. <S> The compromise is older kit, but more affordable. <S> Ok <S> it's not a perfect or ideal build, but certainly isn't a 'bad' build. <S> Next step are offset shock bushings to alter the geometry. <S> Also, I know they are a load heavier but out of preference <S> I run coil shocks, were they air then that'd be ace on climbs. <S> I'm guessing you're after one bike to do everything on? <S> I've got a spare pair of Shivers to stick on for DH fun...looking for a heavier spring too. <S> They are spare though, as mentioned in a previous post, better to get a single kickass fork than enduro and DH. <S> I've been really impressed with those Totems, they've been tuned and soak up huge rock impacts incredibly well. <S> There'll be hardcore enduro riders yelling at this that those forks are way too excessive, but out of the whole build, they make the biggest difference in DH. <S> 180mm single crowns are an excellent midway point for DH and enduro. <S> 8 inches rear travel is too much for regular climbs, but 7 max would be ideal if you are looking for something <S> a little more DH orientated. <S> As I've said, it's not an ideal build but the whole thing's worth £800 odd due to age, but deals with DH superb and climbs <S> well (climbs as in offroad). <S> If money was no object i'd have similar set up, but with a frame of similar weight and travel...and 27.5s. <S> I hope this helps in some way.
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If you are doing this to get a better Enduro and a Better DH bike, I believe this is a really bad idea. Given the manufacturers are fully aware most people have an S ( refer Rule 12 ) of 2 or 3, they spend a lot of time producing a wide range of bikes that in their range, there is one that will as close to a perfect compromise of price/performance/style for everyone. There will definitely be some geometry differences compared to what the manufacturer made the frame you will choose for.
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Is white spirit a too aggressive degreaser? Talking with a friend about maintenance on bikes, he told me he uses white spirit to degrease the chain, as it is effective and also offer some kind of waterproofing in case one forgets to lubricate the chain again. Talking with my bike dealer he advised to not use it, as it is too aggressive and would also remove the lubrification from within the chain bearings. He suggested using a dedicated soap. Who is right? <Q> How do you forget to lubricate a chain after cleaning? <S> If this is a possibility, you a would be better not to clean the chain at all. <S> White spirit is a generic name for different products, exactly what it means depends where in the world you live. <S> Some have a flash point of 20–30°C — extreme care is needed using it. <S> Others with higher flash points and lower volatility are safer (but not entirely safe). <S> All are hydrocarbon based and environmentally unfriendly if disposed of improperly. <S> Care should be taken using them To understand the arguments of what cleaner is best, you need to understand chains. <S> The last thing you want to do is use a cleaner that will strip this lube off the chain, in fact, for the first few hundred kilometers no cleaning is probably best. <S> White spirit is one of those cleaners. <S> Once the chain is older, and this lube is worn off, it needs replacing. <S> Stripping the replacement lube off completely is not problem — it's easy to lube the chain and get the same level of lubrication as you had. <S> So should you use it on new chains? <S> No way. <S> On old chains, it won't matter. <S> Question is when does new become old? <S> Who knows. <S> Easy answer and most (profitable for bike shop) is use a dedicated bike chain cleaner (you buy from them). <S> There are plenty of questions on this site and discussions on the internet about the various religions of chain maintenance you can delve into if you desire. <A> Yes white spirit is too aggressive, it will strip factory lubrication for something like waxing for example. <S> If you want to keep the factory lube then use something else. <A> White spirit is the way to go. <S> After years of messing around, I haven't found any better solution. <S> I'm over 5000 km with this chain now. <S> I'm using a quick-link and chain pliers, which will set you back 15 EUR. <S> You don't need to dispose the white spirit, even if it has turned black. <S> Take an old bike bottle, fill it halfway, take off your chain, soak the chain and shake the bottle. <S> To restore the lube, use a fine layer of teflon after cleaning the chain, and you're ready to go. <S> It doesn't oxidate, but the rings do wear out noticeably. <S> If you also use white spirit on the bike itself (which I do), the lacquer will lose its shine, and I can't guarantee it's good for the sprocket and the hub. <S> It saves you from taking out the pulley wheels though. <S> If you want to be really neat, clean the pulley wheels and the cassette in the same way as the chain. <S> One thing that bothers me is that the whole procedure could take half an hour, while a new chain costs only 20 EUR. <S> If you earn 40 EUR per hour, it's perhaps not worth the effort.
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Just wash away the remaining white spirit on the chain, or use paper and burn it afterwards if you want to save the environment. In the end I don't think it matters, as long as you are cleaning the chain regularly and lubing it properly. New chains come factory lubed with a very robust and long lasting lube that is much better than anything you can apply.
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How does one wear leg warmers without them sliding down? I seem to always have my leg warmers fall down. They seem a little tight, and I wear them under my bike shorts. Are they any tips to keep up around my thighs instead of my falling to my knees? <Q> So I would suggest a good pair of leg warmers with a nice grip on the top, however this still doesn't mean that they wont slip. <S> Shaved legs where they are connecting to is a good way, but a good pair of bib shorts with a grip on the bottom helps. <S> I found my Merino leg warmers would slip even though I had them under my bib shorts, so I made sure I didn't have them pulled too tight, and they were a good few centimeters under my shorts. <A> A trick that Japanese schoolgirls use to keep their knee-high socks up is some rubber glue(the <S> stationery kind not the bicycle kind ). <S> It’s easy to apply, won’t come off with moisture (sweat), but is easy to rub off the skin at the end of the day. <A> I'm using Endura windchill legwarmers, they're fine on the bike, and usually fine when walking (but can start slipping if I haven't gone to extra effort to give them even more room in the knees), they're pretty tight. <S> Observations <S> However I have also found the upper can be TOO tight also guaranteeing slip (the lower seems to be ok with being "too" tight in my case). <S> How I Put Them On <S> I put them on while sitting. <S> I usually put them a bit too high and tight on the lower leg to get plenty of knee room, and get the upper leg "just right" tightness... <S> then faff about getting just the right amount of knee space by pulling the lower down a bit (but still tight). <S> How I Deal With The (Rare) Times <S> They Do Slip <S> I have found that I don't want to pull the warmer up from the top <S> , I just end up with overly tight upper and knee and slippage over and over, instead I want to pull it up from around knee height (i.e. tightening lower area) before pulling it up comfortably tight at the top (if there's not enough knee space, then pull up from knee height again).
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I find I have to get this fit just right on the lower leg and upper leg, with a bit of slack in the knee area, if my knee area is noticeably tight, or either lower or upper leg not tight enough, then the leg warmers are going to start sliding down.
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When shifting both left and right shifters, what's the preferred sequence? My technique has always been "easier, then harder". When switching to the big chain ring, I first downshift at least twice on the right (easier) and then upshift on the left (harder). When switching to the small chain ring, I first downshift on the left (easier) and then upshift at least twice on the right (harder). I find this technique effective because it maintains my cadence and prevents loss of momentum in my legs, especially important when switching to the big chain ring. Does my technique hold water? <Q> I assume it does. <S> At least I do it all the time with an exception that I press both switches simultaneously, or at least without mentally dividing it into "first left, <S> then right". <S> And yes, it typically has the "two on the rear, one on the front" pattern to have a smooth transition. <S> The goal is to achieve a half-step gearing . <S> The huge teeth count difference on modern front chainring doubles explains why it requires a double rear-shift, otherwise the gearing jump is too big and unpleasant. <A> I've generally shoved both levers at once when shifting to lower gears and am out of range. <S> The front and back mechs are unrelated on normal bikes (excluding any fancy-pants electric shifting) <S> For example, If I've ended up in big-big, then stabbing both underlevers once would move me from 46:28 (ie 43.3 gear inches) to 36:24 (39.6 gear inches) from 36:28 (ie 33.9 gear inches) to 26:24 (28.6 gear inches) <S> So its essentially shifting to a "next" gear ratio without being overly complex. <S> I use RSX 3x7 brifters, without trim. <S> 46/36/26 and 12-28. <S> For me, shifts to the big chainring are iffy. <S> The joy of an old bike <S> , so I have no good words on that. <S> Sheldon's gear calculator says the same would function the other way at the small end of the cassette. <S> To say that mess another way, two shifts on the rear + a shift on the chainring is about the same gear ratio (within 1.9 gear inches or 5% at the low end, or 3.3 gear inches and also 5% at the top end of the cassette). <A> In particular, road compact vs standard front gap leads to totally different strategies with shifting. <S> The more gears in back for a given cluster range, the less downside there is to just staying in the same chainring chosen based on the terrain you're in. <S> The technically most optimal gear may still be on another ring, but there are efficiency and enjoyment downsides to doing all that back and forth shifting to stay on top of it. <S> This effect has increased marginally with each speed generation. <S> The greater the chainring gap, the more rear shifting you need to do if you insist on sequencing your gearing exactly. <S> That's a big reason why compact really took off in the days of 10 speed and not 5 speed - with <S> 5 speed rear ends you're priced in to doing that sequencing, but with 10 it matters a lot less. <S> Also the greater the ring gap, the more gear values you're going to have back to back on the same ring at the extremes of the bike's gear range. <S> For example, on 11-speed 34-50 11-25, the top 6 or so gears are all on the large ring and the bottom 4 or so are all on the small, so there's going to be a lot of the time where the most optimal sequencing involves no front shifting at all. <S> Compare that to five-speed 42-52 13-25, where the only the top 1 or 2 and bottom 1 or 2 gears are on their respective chainrings. <S> Again, you're then priced in to hunting around. <S> If you want to master this topic, studying different setups in a gearing calculator like https://www.sheldonbrown.com/gear-calc.html is a good idea.
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It doesn't really work to ask or answer this question independent of rear cluster gear count, range, and chainring tooth difference. Sheldon Brown calls the technique "Double shifting" .
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Question on new bike assembly If I order a Fat Bike online it will come in a box.Is the assembly hard to do for someone fairly good with their hands? <Q> This depends how much it was assembled before going into the box. <S> I've had one bike that just needed the stem bolts to be loosened and the stem rotated, plus the pedals fitted (using tools provided). <S> The one I bought recently needed a little more work but still only using tools you'd carry on the road plus a pedal spanner. <S> That was a used bike, and had been dismantled just enough to go back in the box. <S> The seller should be able to tell you exactly what is required. <S> It's well worth asking them. <S> Important things to be aware of: <S> Some bolts need to be done up to a specific torque. <S> On many bikes this can be quite roughly approximated but on carbon fibre and light alloy you shoudl <S> really get a small adjustable torque wrench (sometimes sold as a torque screwdriver). <S> The parts should normally be marked when the torque matters. <S> The left pedal has a left-hand thread. <A> You will need a decent set of Allen wrenches and common hand tools such as wrenches and screwdrivers. <S> I've assembled numerous bike for friends from a variety of sources. <S> The easiest involved installing the front wheel, inserting the seat post, mounting the pedals and handlebars. <S> Another required mounting the rotors to the wheels, the calipers to the frame, both wheels, bars and saddle. <S> Then it also required some shifter and derailleur adjustment. <S> I would suggest reading some of the Park Tool tutorials. <S> Pay particular attention to derailleur and brake adjustments. <S> While it is not rocket science it can be frustrating the first time you do it. <S> If the bike comes out of the box really out adjustment and your attempt to correct it is unsuccessful then bring it to your Local Bike Shop and pay for the adjustments. <A> As suggested I spoke with Moose Bikes and you don't have to do much more than put on the pedals. <S> This question has been answered.
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Double check that you've got the pedals the right way round, then grease the threads and do them up with your fingers for severalturns before finally tightening with a pedal spanner (a thin 15mm open-ended spanner) The level of expertise required will vary by the brand and the complexity of the bike.
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Is it normal Allen keys are loose fitting? I notice on my chinese made Norco that the keys are very loose fitting.I know there are different sets of allens but I seem to remember them either fitting snugly or not at all. The reason this concerns me isit feels like I could strip the hole especially on the brakes whichhave to be tightened down well. <Q> They all have some play in the fit. <S> The target outside dimensions for the most common bike hex wrench sizes (4, 5, and 6mm) are all around .1 <S> mm less than the bores they fit in, which match the nominal sizes with a tolerance of <S> I think + <S> /-0.05mm-ish. <S> That shouldn't lead you to feel they're "very" loose, but they typically aren't exactly snug. <S> The only exceptions I've encountered are certain 90s BMX stems. <S> That it's Chinese is here nor there. <A> In a word - tolerances. <S> The fastener tends to be oversize and the tool tends to be under the nominal size. <S> http://www.bikeradar.com/mtb/gear/article/dont-buy-the-cheapest-tools-44468/ is a good run down, but the upshot is that the larger the difference between the fitting and the tool, the more force is focused on a smaller area, being the corners. <S> A nominal 5mm hex hole should use a 5mm tool, but if it was exactly the same internal and external size, then your tool would be hard to fit and harder to remove. <S> This assumes your tool is the correct size for the job. <S> Using a 3/16" tool in a 5mm fastener is a recipe for disaster. <A> Ball end Allen keys tend to feel looser than square end. <S> While useful you should only really use them when you have to because the contact area is much less <S> so they wear the screws faster. <S> The tools also round off easily, making it easy to wreck screw heads (even in such a way that they feel fine at home, but then fail with your roadside tools) <A> I was an alarm technician with a couple of other trades thrown in as well. <S> While innovation is essential when it comes to tools and earning a living <S> I agreethe best tool is the one suitable to the job. <S> I use allen keys a fair amount and even fitted one into a battery drill asI had to use it to unscrew and screw one inch long fine threaded screws. <S> Any allen key up to date had a snug fit compared to working on my bike brakes. <S> I went to my l.b.s. and asked if it was normal. <S> My mechanic let me use brand new keys meant for my bike. <S> They had the exact same loose feeling. <S> It may have to do with the fact I am unused to working on bicycles. <S> Perhaps it is the highly polished screws themselves.
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Very loose suggests using imperial aka fractional/SAE wrenches, whereas virtually all Allen bolts on bikes are metric. If you don't own the right tool, buy the right tool, whether it be a workshop P handle driver or a quality multitool for on-bike.
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Maintenance for an idle bicycle kept indoors? I have recently bought a six-speed transmission bicycle, basic yet the latest one. But owing to my busy schedule I am not able to go for a ride on it, and the cycle is always left idle at one place. So, I wanted to know how I can at least maintain my bicycle, so that it doesn’t rust and stays healthy. Bike is always kept indoors. <Q> A lightly-used bike stored indoors in a dry (not humid) environment does not need much special maintenance. <S> The tires will slowly lose pressure. <S> A bike left sitting for a long time on one spot on un-inflated tires is probably not good for the tires or tubes. <A> As @Argenti Apparatus said, it is crucial for tires and tubes to keep them inflated. <S> Additionally, if you cannot hang it, at least change the tire - floor contact point by rolling the wheel. <S> You can also spray it with i.e. silicone compound for rubber parts. <S> Clean and grease your chain. <S> There is often enough humidity in the air to make not oiled chain to corrode. <S> Make sure that bearings are greased. <S> If not - repack and grease. <S> I would personally oil brake and shifting cables. <S> Use proper bike lock or even thick chain that you would not normally use and check periodically against theft issues. <A> Answer: <S> Park it inside, or in a garage. <S> If you don't have anything like that, at least park it under cover out of the weather.
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Keep some air pressure in the tires or hang the bike up off the floor if you can. Just keep it clean with light lubrication on the chain. The quickest way to ruin a bike is to leave it outside in all weathers. Protect rubber parts from the sun - keep the bike in the shade or cover it.
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Why are bicycles priced the way they are? This question may not fit the criteria here.Feel free to close or edit it. I spent six hundred dollars Canadian funds on a Norco Yorkville Hybrid.The rationale being that for that price I would get better than an entry level bike. It's a retirement gift to myself. I deserve better than an ordinary bike after forty plus years work. Now it has become evident that while it is a good bike it is rather ordinary. I look around and see riders spending one,two and almost three grand for what they want. Is this just a case of buyers remorse?I like the Yorkville. It is nice looking but I wanted something special.A bike that performs better than average.Why are bikes priced the way they are? <Q> Simply put, you are paying for the research and development that it takes to produce the top end framesets and groupsets. <S> It takes a lot of time, trial, drafting, creating, testing, and reiteration of all the above steps to create a marketable product that also performs. <S> (To some extent, you are also paying for the free product that goes to sponsored teams, but that is much smaller slice of the pie). <S> The good news, especially if you are working from a limited budget, is that you don't necessarily need the top end, current year models, unless you are intending on riding it for quite some time, or you really do need the small edge that the latest and greatest will give you. <S> The reason for this is that technology trickles down year after year, and/or you can purchase top of the line a couple years later for a much cheaper price. <S> I don't know the exact rate at which technology does move down, but the current SRAM Force group (Their mid range groupset), is probably just as good or better than the Red groupset of a few years ago, because as the Red group evolves to be better, they don't get rid of the older tech, it just bumps down a level and becomes Force, and the old Force bumps down to Apex, etc etc. <S> (That is very simplified, but basically true). <S> Or, because you don't need that slight edge, you can buy a used group a couple years down the line for much less than new. <S> The same holds true for bike frames. <S> For a long time, the gold standard in triathlon frames was the Cervelo P3, which outperformed just about every frame around, even 4-5 years after initial release. <A> How is any product priced? <S> There are three factors: <S> The cost to develop and manufacture the item, and cost of marketing and sales networks. <S> The demand for the item and what people are willing to pay Volume, the more units made and sold the lower the item cost <S> If you look into what goes into making a carbon-fiber frame you'll see where some of the cost comes from - it requires human labor and is difficult to automate. <S> Bikes are not a huge volume product - compared to say smartphones or laptop PCs. <A> Part of the price is materials employed, part is assembling know-how, the remaining (good) part is brand. <S> (Which is why you pay a Mercedes way more than a Dacia) <S> My approach with any sport apparel has always been pragmatic: "start with low gear, once you get real better improve the gear". <S> With bikes this meant riding my first 15k km on a low end bike, which I still use to commute. <S> That same bike was also my "horse" for the first two cycling holidays, riding up and downhill on the Italian Appennini. <S> With that bike I became able to overtake cyclists riding a 1k Euro full suspended MTB on paved roads (sic!)' <S> Then I decided that switching to a better bike was worth it, an moved to a slightly more expensive bike (900 Euros back then). <S> In the town were I lived before there was a skilled craftsman who was really good in hand making bikes. <S> For one of his works you could easily spend 12k Euros or even more. <S> Personally I would never put that much money on something that still requires my leg to move.
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Yes, it's always fun to get the new shiny, but unless you are at the pointy end of the spectrum, you will get much more bang for your buck buying a few years old. At the very end it's not the bike that performs better than ordinary, it's your legs. While the newest framesets have all the aerodynamic and construction/design tweaks that hours in the wind tunnel produce, you can easily get a top of the line frame from a few years ago and reap most of the advantages that you would need.
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Weight limit for my bicycle i bought my mountain bike litterally an hour ago but i feel im a bit to heavy for the bicycle.I weigh 120kg (backpack weight included).Its a Avalanche Reflex 29er 2018 model with a size 20 frame.Am i just being paranoid?If its the wrong size then ill just have to do an exchange so any help ASAP will be appreciated as it will be my transport to, and from work <Q> 120 KG is 265 lbs. <S> You might want to contact the manufacturer to get an exact number on the recommended maximum rider weight. <S> Usually aluminum/alloy frames are around 300 lbs while carbon frames are around 250 lbs. <S> This isn't because carbon is weaker, but rather because carbon bikes are designed with a different kind of rider in mind. <S> Double check with the manufacturer, but you are most likely fine. <S> You may have problems with bent spokes if you are rough on the bike, but the frame should be fine. <A> Most of the times the frames aren't the biggest issue with weight. <S> But in the end it depends on what you mostly ride with the bike. <S> If it is mostly commuting you should be fine. <S> As said before the front shock could also become a problem. <A> Your bike has an MSRP of ZAR3575 which equates to around US$285 or €240. <S> Assuming that it’s sold for less than 80% of MSRP that means it’s a 200 eurodollar bike. <S> That’s firmly BSO or flat pack bicycle territory . <S> The squirreliness that you’re feeling could simply be that the bike is poorly built or assembled. <S> Most BSOs are sold out of mass market retailers (supermarkets, department stores) and the minimum wage clerk who assembled it out of a flat pack might not know anything about chain alignment or proper torque values. <S> But to be honest, it’s often impossible to properly assemble a BSO as the manufacturing quality is so low and the materials used so suspect. <S> If your budget is sub-200 Eurodollars, you would do much better getting a used, brand name bike - preferably from a bike shop that has refurbished it. <S> Now, as other answers attest, most bikes have a 100-150kg or so maximum weight limit. <S> For gentle commuting, even at your weight you wouldn’t be putting the bike through the types of stress a 75kg semipro rider would be putting on it riding off-road.
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However on quality MTBs, that weight limit is calculated assuming the rider is going to be doing jumps and otherwise bashing the bike hard. tl;dr - You have a cheaply made bike which is why it's squirrelly, I’d return it and get a quality used bike. Especially if theses are cheaper 29" wheels you should check the manufacturer for a weight restriction. Other bikes by high end manufacturers usually are around 250-300 lbs. What's mostly limiting are the wheels.
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Type of Shimano "PlusMinus" (slot & Philips) screws Shimano uses a screw type that is a mixture between slot and Philips (PH): There's a "PlusMinus" screw type for electrician equipment like manufactured by Wiha : (Source: Wiha ) Are the Shimano screws officially PlusMinus types? Are they officially Philips (PH) compatible? <Q> The limit screws you mentioned just are extended a bit to handle a flat screwdriver if that's what's handy. <A> The point of these screws is that you don't need a specific driver. <S> It's just a combination head that will accept either a flat or cross-type driver. <S> Given that your actual screws are worn, you can't really tell what sort of drivers they were designed for. <S> However, at the sort of torques you need to adjust a derailleur, the difference between Phillips and Pozidriv shouldn't be significant, so any of flat, Phillips of Pozidriv should work just fine. <A> It is simply a dual drive screw. <S> Use flathead or phillips drivers(probably a size #2). <S> They don't support much torque either way, if you use the screw frequently then replace it with a proper drive like roberston, torx, maybe $0.15 $1 for stainless steel. <S> If you work in a shop just buy a small box of each size in the better drive style. <S> For a while in the late 90s and 2000s east Asian manufacturers seemed to occasionally mix in those weird posi-drive screws as they kind of look like phillips <S> but I think that has become less common. <S> (personally I would like to see Robertson square drives replace all Phillips <S> , I hate Phillips its one of those antiquated standards used only because it was popular long ago <S> and everybody has one. <S> Phillips is actually designed to cam out as it predates power-driver clutches.)
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As far as I know, every cross-type Shimano screw is JIS, or at least they are in the sense of being designed to mate correctly with a JIS screwdriver.
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(Apparent) chain slippage causes on new bike - usual culprits already eliminated I recently purchased a new bike (~7 weeks ago). Since day one, it has had an issue with chain slippage. I initially took it back to the bike shop from which I bought it, to be told that it was likely just down to "cables not yet being bedded in" and told to "just give it more time". (I am more than aware that cables don't need to "stretch" once installed; after a ride or two, the only thing that will change is cables/ferrules/etc being properly seated in their housing, and stable) Given that reaction from the bike shop, I have tried to locate the problem myself. How the problem presents itself: When pedaling normally, the cranks slip in a way at least similar to chain slippage. Typically, I hear a few single 'popping' sounds as if a part is moving back and then forth, before finally feeling the chain jumping feeling. Note that I only say "feeling" - as it could well not be the chain jumping, but something else which feels like that - the cranks rotate freely through what feels like 1 or 2 cog teeth (from experience), but perhaps it could be the freehub body? It doesn't happen during shifting - shifting performance is good It doesn't appear to matter which chainring I'm in It doesn't appear to matter which end of the cassette I'm in It is not caused by cross-chaining (I avoid cross-chaining) It doesn't appear to matter whether or not the system is under high load; it still happens when pedalling moderately It doesn't happen "regularly" - ie, it isn't every pedal stroke/every chain full revolution/etc. Sometimes it will happen multiple times in quick succession, and other times it will be 10 mins between occurences. Here are the key facts and what I have noted to try and eliminate possible causes: The parts are (of course, being a new bike) all new - no wear on the chain/jockey wheels/chainrings/cassette. The parts match - all are part of a Shimano 105 groupset (no aftermarket/3rd party parts, including chain and quick link) There are no sticky links in the chain, having checked the entire chain The bolts on the chainrings are properly tightened The bolts on the derailleur hanger are properly tightened The derailleurs are both properly indexed and high and low limit screws are set properly The rear derailleur hanger does not appear to be bent The chainrings aren't bent and are in alignment The cassette cogs aren't bent and are in alignment, and secured properly on the freehub body Frankly, I'm out of ideas. In the first instance, I am going to take the bike back to the shop to be looked at once more (now that I have "given it more time" as requested, however dubiously). That said, I would still like to understand possible causes of this in case they aren't able to or are unwilling to find the root cause. What could cause the above-described issue which hasn't been covered off by the above checks? EDIT: for reference (since it's now relevant having solved this issue): my bike make and model is a Pinnacle Arkose 4 (2016), the groupset is full first-party Shimano 105 and the wheel set has KT hubs. <Q> If everything is shifting smoothly and the hanger is aligned, it's very likely the freehub body slipping intermittently, which feels much like the chain slipping. <S> Usually it takes a visual to be sure it's the freehub and not the chain. <S> Different freehub designs call for different procedures to fix and investigate this. <S> I've seen both on new and new-ish bikes. <S> Ideally at this point one would put their eyes on the freehub internals themselves to check for damage, which can occur from skipping with partial engagement, often in the form of a pawl tooth getting blunted or torn. <S> Some designs make such a check easy, i.e. many cartridge bearing hubs, but others make it impractical, like generic OEM cup and cone hubs where freehub disassembly isn't really intended to be possible. <S> The good news is that usually it's just some overly thick lubrication at the pawls and fixing it is often as simple as getting some light oil worked in to reduce the overall viscosity. <S> Usually Tri-flow or similar. <S> If it's a "closed" design freehub it can just be dripped in at the crack, sometimes by temporarily pulling a seal first. <S> By taking the cassette off the wheel and turning the freehub by hand, experienced mechanics can take a pretty good guess whether there's something wrong inside. <S> Not 100% accurate <S> but there have been many times where I've done this and found it to be obviously rough or felt something jangle inside, implying a spring issue. <A> The freehub was the issue. <S> As it turns out, the bicycle manufacturer (Pinnacle) have issued a recall on the rear wheels of a small number of units of both my bike model (Arkose 4, 2016) as well as another model sharing the same rear wheel (Arkose 4, 2017). <S> It seems there were manufacturing defects in a batch of rear hubs/freehubs, causing the pawls to fail to engage intermittently. <S> My rear wheel has been replaced in its entirety by my local bike shop (Evans Cycles, UK) under this recall and the issue is now resolved. <S> Link to my LBS recall post for reference, including serial numbers of affected units <A> The rear derailleur hanger does not appear to be bent <S> How are you so sure the rear derailleur bracket isn’t bent? <S> A bend of just a few degrees - which is not visible to the human eye - is enough to throw off the chain line. <S> Such a bend can easily happen in shipping or even when parking your bike against a parking post. <S> All bike shops and most bike coops will have one. <S> It does necessitate unbolting the derailleur from its bracket but is otherwise a 10 minutes job.
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The root cause could either be overly viscous/gummy lubrication causing the freehub pawls (or other engagement element depending on the design) to not spring back rapidly enough, causing incomplete engagement, or an issue such as a broken, mangled, or out of place pawl spring. The proper way to measure derailleur alignment is with a derailleur alignment tool.
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Cause and diagnosis of wobbling crankset/chainring I was replacing the chain recently. When spinning the crank I noticed that the chainrings are slightly wobbling along the axis. I was able to see the wobbling with my eyes. First check I kind of verified the wobbling by holding a screwdriver next to the largest chainring's teeth. When spinning the crank it was touching the teeth when the right hand side crank was the bottom. The wobbling was in the range of 1mm - 3mm. I removed the crank from the bottom bracket. Then I pulled and spun the bottom bracket axle to verify it's not loose or grinding or wobbling itself. It was OK, no slackness, fluently spinning, no noise. Note that, though it looked fine, back then I had problems fitting the new bottom bracket due to a damaged bottom bracket thread. Fortunately I had a spare crank set at hand. I attached the left hand side crank at the right hand side. Now I had two cranks attached, none with chainrings. The idea was to match the cranks for their masses and eliminating any imbalance of the chainring crank compared to the left crank. Then I gave the crank a hefty kick assuming that, if the bottom bracket were off-axis, the cranks must wobble, which I could feed and maybe see. Holding the bike firmly perpendicular I felt no major wobbling of the bike. So I assumed the the bottom bracket is on-axis. Not knowing how to further diagnose the problem I reassembled everything and finished the chain replacement. Second check After a couple of kilometers cycling I checked for the wobbling again using the "screwdriver method" (this time with the chain in place) and the wobbling appears to be gone. Additionally I did another check with another method: Pointing a laser beam perpendicular onto the chain's teeth "bottom land" orthogonal to the axis. Then I spun the crank. The idea was, that if the chainring was wobbling, the laser beam must "touch" the chainring plane. This time I was unable to detect any major wobbling. Other issues Before dis- and reassembling the crankset I had a clicking sound for months when pedaling. It only happened when putting force on the right hand side crank and only along the way from the crank arm was parallel to the ground to when the pedal was at the very bottom. (Inspired by one intermediate answer: it might have occurred when the force reached its minimum.) I narrowed it down by putting force on the pedals separately and at different positions (angles). The clicking sound is gone now. Re-seating the cranks was on my to-do list for isolating the clicking sound anyway. I also had the problem of a slipping chain covered in another question. Though it might was caused by another issue (mentioned in the other answers), that issue might be related to this one too. Further: I now realized that a periodic scratching sound of the chain on the front derailleur arm may have had its cause in the wobbling. What was wrong? Could I have attached the crankset badly during the previous assembly? Is it likely that a octalink crank may misfit the axle (mounted at a non-zero degree angle for example)? Is it unlikely that there was a wobbling in the first place that could have been cured by re-assembling ? I mean, if there was a wobbling and a clicking that are now both gone, I find it very likely that there was definitively a fault. I want to understand possible faults and causes I should look out and avoid in the future. May the misalignment, if there was any, have permanently damaged the crank or the bottom bracket? Since I had trouble with the bottom bracket thread, might the bottom bracket be misaligned by some millidegrees? Setup Crankset FC-T521 (octalink) Bottom bracket BB-ES51 (octalink) Edit: added a little more explanations and clarifications to observations and questions <Q> As you put maximum torque on a pedal, a loose fit on your bearing allows the crank to force movement in the bearings outside the bearing race. <S> They can then click back in as pressure is released. <S> This matches up with having a "wobble" in your chain ring. <S> Tightening things back up can very easily have solved your issue - although be aware of any future problems, as the time you spent with the clicking noise would have induced more wear. <S> I had this problem many years ago, and ignored it (I know...) <S> and by the time I got round to looking at it I had to replace a number of components that were damaged... <A> From your description something was wrong with setting crankset onto the bottom bracket axle. <S> It could be not tightened enough, there could be some dirt between octalinks, that affected the whole set and caused it not to be laterally true. <S> If the bottom bracked is tightened properly and you, despite thread issue, are able to tighten crankset, you don't have to worry about. <A> Octalink cranks are very easy to mis-align the crank arm on the spindle. <S> By taking it off and reinstalling it, you solved your "wobble" issue. <S> Just take care when doing any more maintenance on your crank set.
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For me, that clicking sound nails the diagnosis - the only thing I have ever seen that causes that is an issue with your bottom bearing - either it isn't tightened up enough, or the bearings are worn and can slip.
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How to get a broken torx bit out of a bleed screw? In the latest episode of my disastrous bike maintenance attempts, I got a sub-standard torx bit that broke off in the bleed screw of my Tektro Vela disc brake caliper. Here's a sligthly overexposed picture of the brake caliper in question, the bleed screw is circled in red: And another shot from the side. Notice how the bleed port is recessed rather than the bleed nipple you'd usually see on a Tektro brake. Considering that the screw is slightly recessed into a somewhat expensive safety device, I'd like to find out a way to get the bit out in the least destructive way. If all else fails, I'm considering eating crow and taking my bike to the LBS in the hope that they'll have the tools, experience and/or spare parts to fix this. <Q> From the photo you posted reasonable option is to drill a hole in the bit and use drill extractor, spinning it anti-clockwise. <S> Bit is made of hardened CrV steel, so drilling it may be hard, since it should be precise and centered. <S> If you feel unsure about your skills, give it to professionals, to locksmith or to your local bike service. <S> It may appear cheaper, since damaging caliper housing would be much more expensive than spending some extra euros to have it fixed. <A> Do you have access to a drill press? <S> Good answer from krzyski <S> but you don't need to extract. <S> Start centered and use bigger bits until the torx bit fractures. <A> If the bit broke from being defective and not from too much torque, it may be as simple as turning the bike upside down and gently tapping the caliper with a hammer. <A> I would try alternating heat and cold. <S> Heat from a hair dryer (since your parts are painted, you can’t use a propane torch) or the tip of a soldering iron. <S> Cold using an upside down “canned air.” <S> Wear eye protection as the bit can fly loose. <A> It's a tiny bolt (maybe only around 5-6mm across) <S> so drilling it out and getting a screw extractor in might be a bit tough. <S> You might consider using a dremel rotary tool with a thin drill or abrasive diamond bit. <S> You want to drill a small hole in the center to get the screw extractor in -- or perhaps more realistically a straight trough into which you can fit a flathead screwdriver so that you can unscrew the bolt. <A> Getting a replacement bleed screw for this brake may be pretty difficult (or Tektro may just have one to send, who knows). <S> It is critical to use the right screw and o-ring so that the seal works. <S> Cow magnets are pretty strong and readily available, and the right shape. <S> Of course a pickup magnet or computer magnet may be more readily on-hand. <S> There may be some creative way you can figure out access to an electromagnet. <S> Drilling into the tool steel of the broken bit without destroying everything else does not seem very realistic to me. <S> In theory you could find something to bond a tool to the screw and broken bit, unscrew it, then use heat to undo the bond. <S> In practice whenever I try something like this the bond doesn't really get strong enough. <S> Using an adhesive to pull on the broken bit is pretty likely to get it stuck in worse, although it's true that in theory this might be avoidable. <S> You have the advantage that the broken parts probably want to mate closely and provide lots of surface area. <S> You might try cleaning the surfaces with alcohol on a q-tip, put a very tiny dot of epoxy on the connection point, sticking it on and securing with a rubber band, and leaving it for its full cure time. <S> If you can avoid using enough epoxy that any spills out the crack of the bit, you should be safe from making it worse this way.
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If there's a way to get out the broken bit with a suitably powerful magnet, that's got to be by far the approach that causes minimal further complication. It’s even better if you can get some moisture underneath the broken torx bit as you heat it up with the soldering iron tip.
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Will a 2x with a clutch RD be just as effective as a 1x with a clutch and narrow-wide chainring on an mtb? I am continuously dropping my chain on my enduro mtb rides (currently 2x). The rear derailleur that my bike is currently running is a deore non-clutch. My chain will normally drop after riding rock gardens, jumps, and drop offs. My friend says that even if i get a clutch version of my current derailleur I will still drop my chain and that I should just convert to 1x. But a 1x conversion is more expensive and will lower my gear range. So I would like to know if a clutch 2x will have the same effect? Note: My bike was new 2017 but has had hard use, the bike is a feul ex 5 <Q> It will help 2x, though 1x is going to hold chain better. <S> I think you'll still see an improvement with a 2x setup due to added chain tension. <S> When I upgraded the drivetrain on my full suspension to use a 10spd Shimano Deore clutch derailleur it didn't drop chain nearly as much if ever. <S> Make sure you have your chain shortened to the appropriate length as that's one of the biggest factors causing chain slap and <S> jumps is having a chain that's too long. <S> A 1x would likely work better if you switched to a narrow/wide chainring that prevents jumps though. <S> The front chainring does a lot to stop the chain from slipping off due to the tooth profiles that really keep the chain engaged. <S> I'm running a cheaper 10 speed setup on my hardtail with a sunrace 11-42 casette with a 10spd sram <S> x-9 clutch derailleur <S> and it works very well and was a cheap upgrade vs a whole new 11spd. <A> Its not as simple as that. <S> The difference between 1x with narrow wide and and 2x is both should not be dropping chains, ever. <S> Most people <S> I know who fixed problems by going to 1x <S> said something like <S> "My new 1x is a vast a improvement over my x years old worn out drive drive line, ho ra for 1x hail the 1x..... <S> " <S> (Followed no longer after by something along the lines of <S> "Shut up about the 1x already"). <S> These people also largely forgot they when their bike was new they never had issues. <S> Upgrading to 1x means a completely new drive line so of course it will work. <S> Upgrading just the rear derailleur means just a new rear derailleur, so it might not work depending on the state of the drive line, especially the chain rings. <S> If you 2x is dropping chains, something is not setup ideally - worn components, adjustments or bad chain line. <S> Upgrading to 1x will fix the worn components, but is most likely to make the chain-line worse unless you take great care or the BB has been changed on your existing setup. <S> If you need new chain-rings, a 1x would cost a bit more, but would be a better way to go. <S> The question you need to look at is cost - you could upgrade a few components to say XT level and keep the 2x, or deore level on 1x for similar money - which is the better drive line. <A> Switching to a clutch rear derailleur will help retain the chain. <S> It's hard to say whether a 1x drivetrain would work better. <S> Don't forget that with your 2x you have the front derailleur helping to keep the chain on the rings.
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IMHO provided you chain rings are in good condition, an XT clutch with new chain (and cassette if needed) will outperform you current setup of clutchless Deore. I almost never drop a chain on the 1x setup with a race face narrow wide ring.
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Relation formula between fork length change to headtube angle and bottom bracket height As we know, changing the fork length will change bike geometry a bit. For example, increasing fork travel by 10 cm will make the headangle slacker and raise the bottom bracket. I consider to increase fork travel on my bike by 20 mm, and to fix the increase in bb height with some headangle changing headset (like Cane Creek angleset). While I don't mind my bike to be slacker (actualy it's one of the goals of this modification), I do want my BB stay on the same height. Is there any formula we can develop to understand how would a change in fork length influences the headangle, and how the headangle influences the BB height? <Q> This isn't a formula for you so maybe not the answer you're looking for, but <S> it gets tricky because a fork isn't just a straight line; because it has offset it's kind of like a triangle itself for the purpose of doing the exact math here. <S> The thing most people who care about this question would do in practice is model the frame's fixed points in a 2d CAD program, model the forks in question (remembering that to do <S> so you're making a right triangle where the axle to crown dimension is the hypotenuse, the offset dimension is one leg, and the other leg is an unknown length that can be solved for or figured out automatically in CAD), then plug each fork in to the frame model such that the unknown leg is in line with the head tube, and then pivot the whole thing around the point of the rear axle until the front axle snaps to being in plane with the rear. <S> Then you can see the resultant head angles and BB heights easily. <S> You can also easily see what angle changes at the headset would give you. <S> There are many free 2d CAD programs that can do all this. <A> I'm not that technical <S> and I did dismally at maths. <S> So I'd lean the bike against a light coloured wall, stand back and take a photo of it from a distance (to reduce parallax and distortion) <S> Try and squat down <S> so the lens is about in the middle of the bike. <S> Measure your current fork length, and print your picture TWICE onto paper. <S> (example 480mm) <S> (example 53mm)and divide by the real length, <S> (example 53/480 = 0.1104 <S> This is your scaling factor.) <S> Now find the length of the new fork - this is harder if you don't have it, and published specs might not measure like you want. <S> (example 566mm made-up) Multiply that new fork length by the ratio (566 * .11) <S> to get 62.3mm Draw directly on your picture a fork that is now 62.3mm long, or 9.3mm longer than the pictured fork. <S> Cut out the front wheel from your second copy, and pin or place it accurately on the first picture, but at the end of the new fork line. <S> Tape it down. <S> Finally, rule a new straight "ground" line that just touches the rear tyre and the new front tyre. <S> You can measure the new BB height from your composite picture, and then divide by the scaling factor. <S> (say the page measured 15mm between BB and new-ground, so <S> 15/0.11 = 136mm) <S> Note this will be Unladen, or "unsagged" fork length. <S> Ideally both forks will have the same sag settings, but its still just an approximation <S> Also, my sample measurements are completely made up, and yours will vary. <A> The math is fork length X cosine of the angle for height. <S> If straight up and down the angle is zero. <S> Cane Creek angleset is only 1 degree so it might not be enough.
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Accurately measure the printed bike's fork length on the paper
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Is this old chain of a different type? My friend's bike needs a new chain. Looking at the chain, it looks like the pins have a slot for a flat head screwdriver? Is this just cosmetic or does this type of chain require unscrewing the pins? If so could it be replaced with a regular modern chain (of appropriate type [10-speed road])? My question is referring specifically to the pins of this chain which are visible in the attached photos. You can't see it in the picture, but the chain is HKK brand and it was on the bike when he bought it (used) <Q> On some there's some level of intentionality to it as a shift aid. <S> There are no bike chains where all the links are screwed together. <S> (There are some half-link styles where the pin screws in place, but that's a tangent.) <S> The pictured chain is an older bushing-type chain, which was the norm until bushingless chains took their place. <S> From the look of the cranks/rings/guard the bike is a bike-boom era 10 or 12 speed (as in 2 front chainrings and either 5 or 6 rear cogs). <S> If so, chains specific to such drivetrains, which are labelled 5/6 speed usually, are still made and available. <S> You could order one, but many shops don't carry them, instead choosing to use more modern 8-speed chain for replacements on such bikes, which works perfectly. <A> You'd take them out using a standard chain breaker. <S> Newer chains tend to use a different process to join chains together so that mark isn't visible anymore. <A> No. <S> Measure off 12 links (12 inner and 12 outer) <S> and it should be exactly 12 inches long. <S> if its 12 and 1/8" long for 12 links its totally dead and you need to replace the cassette. <S> Often the chainring is savable, because it has more teeth to spread the load. <S> Yours look okay.
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Different chains, including modern ones, have all sorts of patterns or markings on the tips of the pins. The horizontal marks on the rivets that you think are screw heads are just an artifact of the older riveting process. Its just drastically badly worn and needs to be replaced to avoid skipping and mis-shifts.
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Do bike frames actually break so easily? I've been thinking of getting an MTB. Watching all those videos on YouTube of people doing cool stunts or even just riding in a forest off-road looks amazing - until I got to videos like this one: I've seen lots of posts on how to prevent breaking a bike frame, and I completely understand that the maintenance of bike should be regular, but are all these broken bike frames only because of bad state of bike itself? I've got some friends who have broken their new MTB in few weeks of riding, was it just coincidence? My question is: do bikes actually break that easily? That may sound like a noob question because, yeah I am not into biking at all. And I am looking at getting an MTB. (I can drive bikes pretty well, on roads.) Thanks for any comment, answer, upvote or downvote (oh and yes if you downvote tell me why so I wont repeat my mistake) <Q> No, they are not, if used in a way they are designed to and regularly checked for health. <S> I think that a proper answer to your question should include statistical information on what percentage of bicycle frames (btw, why only frames? <S> wheels, handlebars etc. <S> break too) break over the time. <S> The reason of a breakage, such as crash or manufacturing defect, should also be taken into consideration. <S> However, I do not possess such information. <S> So instead I want to warn you against being affected by the survival bias effect by only looking at "bad" examples. <S> I want to comment on several points in regard to the video above, or any other bike crash footage. <S> We do not know how often and how hard these bicycles were crashed before they finally gave in. <S> Quite a few crashes in the video were caused by front wheel detachment. <S> That's not frame but fork issue or rather user installation error. <S> A couple of episodes demonstrate just direct crashes. <S> Nothing is guaranteed not to break after that. <S> I am not sure that all of these bikes were used in their intended discipline. <S> I've had bad experience riding an XC hardtail on an DH course. <S> The good thing is, even after all these crashes most of the riders were able to walk away from them more or less fine. <S> That stresses proper use of personal protection. <S> P.S. <S> Every bicycle user manual that I've read ( <S> and I am one of those weird people who actually read manuals to things) <S> states that bicycling is inherently dangerous activity . <S> Not just MTB but any cycling. <S> So, wear protection appropriate to your discipline, know your skills and improve them, regularly take care of your bike, and have fun! <A> Generally a name brand bike frame (not a big box store bike) ridden within its design limits won't fail. <S> Most of the videos show bikes being ridden beyond what they where designed for. <S> The image in your link shows someone going off a 5 foot ramp on a 30 year old rigid framed "mountain bike". <S> If that bike were made today it would be classified as a road hybrid. <S> Most of the major brands have 4 or 5 types of mountain bikes. <S> They vary by how aggressively they can be ridden or the terrain they can handle. <S> If you ride a cross-country bike on a downhill course you are likely to see component failure. <S> It is less likely with the appropriate equipment. <A> Watch the video carefully. <S> Very few of those are professional riders, most are amateurs with (presumably) little knowledge of proper maintenance. <S> A few examples: <S> At ~ 1:00 in the video - Working on (I think) <S> a bunny hop, but basically just slamming up and down on the front tire/frame assembly. <S> 1:26 - Misses the landing, with way too much front weight on a high drop. <S> 1:40 - Again misses the landing area, with most of the impact being taken by the frame rather than shocks. <S> 2:20 - Runs into a tree at speed. <S> So rather than blame the bike, realize that it is most likely going to be user error or a stress beyond what was intended by the manufacturer. <S> Although, I would also make sure that while it looks cool, you need to realize that even the amateurs in the video spend hours practicing, and working their way up from basic trails/tricks to the stuff you see in the video. <S> Along the way, you are definitely going to break a frame or two. <S> It's the nature of the beast. <A> There are many scenes in that video of bikes being ridden well beyond their intended use, and consequently failing. <S> There are some scenes where a bike fails despite not being abused. <S> That does happen occasionally. <S> What you are not seeing is all the millions of times <S> bikes <S> did not fail. <A> I would suggest that the range of conditions you can encounter on a mountain bike are wider than most other bicycles. <S> That makes it easier to break a mountain bike because you hit something unexpected. <S> I'm a roadie. <S> Our bikes are built much lighter and you can ruin one (especially the really light ones) hitting a pothole. <S> For us, that is outside the expected use. <S> You can ride a mountain bike in reasonable terrain with good assurance it will survive. <S> How do you assure that the terrain is reasonable? <S> It's hard. <S> You might ride a reasonable trail but miss a curve and hit a tree. <S> As you ride you will get a better feel for the risks. <S> You need to decide if they are reasonable for you. <S> You don't have cars to worry about. <S> Ride with others, learn from them, and have fun. <A> No they do not break easy <S> these breakages are due to extreme stunts being performed on a bike that is not intended for these stunts
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Many of those "bike failures" are a direct result of over stress on the frame compounded with user error. Damage, especially in carbon parts, is not easy to see without special equipment. This not to say that even with the best components a serious crash won't break things.
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How do I improve my cycling at my age (77 years) I am 77 years old and newly come to riding a road bike. In the better weather I do between 75 and 100 miles per week, consisting mainly of fairly easy roads with four or five reasonable hills, depending on length of rides. I do routes of 17 miles, 23 miles and a Sunday ride of 40 miles. I average speeds of about 14 miles per hour and can get up all the hills but fairly slowly, I have trouble standing up to rest or get a boost in climbing. I do stretching and power exercises and three lots of HIT on an exercise bike each week. I cope with my mileage OK but would like to improve my hill climbing. <Q> You are already doing quite a bit of training. <S> What might help is training on hills specifically, or when on the trainer, raising your front wheel to simulate being on an incline. <A> One thing I found useful was to track my progress over time. <S> I run Strava on a smartphone, and it records my ride and how I did at any given point. <S> This lets me compare my earlier trips with later ones. <S> Here's an example of a fairly strenuous climb: <S> This shows my first efforts were above 45 minutes and approached an hour. <S> My best effort so far is under 24 minutes. <S> I find this to be a good motivator. <S> The downside of strava is that it defaults to showing you everyone's efforts, and it can be disheartening to see your effort as #997 of 1000 attempts. <S> So the trick is to change the options to display "my efforts first" or similar. <S> That shows where I have ridden, and what roads I have missed this year. <S> This helps by showing roads I haven't used, so are candidates for the next big route. <A> Light riders clearly favor standing up more than the heavier. <S> Standing up is (as anything else) a matter of specific training, and by time then, the ability of continous standing up will increase. <S> When boosting, lean less on the handlebars by shifting the weight to the rear, if required. <S> For the ultimate relaxed, yet efficient style out of the saddle, do not lean too heavily on the hands and arms, though. <S> Also, practice standing when down in the drops, for a short boost. <S> There is no mention of group riding; if that be the case, try to spare yourself on the preceding flat (strategical drafting) to have more ressources left for the hill. <A> First, good on ya. <S> I'm 50, and I got back into cycling 9 years ago. <S> I still remember my first Club Ride in 2012. <S> It was about 12 miles, and I thought I would die. <S> Today, I bike commute mostly year round, 5 miles each way <S> , I do Club Rides of upwards of 60 miles, and I've done two Century Rides. <S> Look around for a Bike Club near you and consider joining. <S> I find that riding with others is a great way to push myself more. <A> I would suggest that you also ask your cardiologist, how hard you can train, it is a good thing to do as I also did as I am 63 years old. <S> His advice for me is "train as long as you like but keep your heartrate low".
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As my Ride Leader says, the secret to hills is riding more hills. I also map my rides using http://www.jonathanokeeffe.com/strava/map.php to combine my year's ride. One can relieve the legs by leaning the hands quite heavily on the handlebar/grip when standing, transferring the weight a bit forward and thereby letting the arms carry part of the bodyweight; also useful in the learning period. Trivial, but nevertheless, as bodyweight range is not supplied: For an optimal hill performance, strive to keep (body)weight suitably low. Note that the cadence standing up usually must be lower than when seated.
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Flashing light when pushing bike with (constant) low speed When someone pushes his bike beside him in a constant (low) speed the light will not be at constant (low) brightness, instead it will flash with it's full brightness. Why does it work like that? <Q> This happens because the power from a hub dynamo (which technically is a magneto, not a true dynamo) is not clean sine-wave AC but consists of short pulses with alternating polarity. <S> At high speeds these pulses follow each other fast enough that a LED can burn continuously with a small capacitor and a filament bulb does not have time to cool down between pulses. <S> The effect does not have anything to do with programming or the fact that LED is a diode, and it happens with filament bulbs too. <S> A more complex LED setup could have a capacitor to enable continuous dim light and perhaps even be programmed to flash at low input power, but I doubt this is the case. <A> If the light is LED and the dynamo has no AC to DC conversion circuit, then the LED should turn on when it gets the right polarity and turn off when it gets the reverse polarity. <S> When the AC frequency is high (which is when the wheel is spinning very fast) <S> the flickering is not noticeable. <A> If there is a super-capacitor in the system it will need a full charge before permanent full brightness. <S> A bright flashing light <S> it is more visible than low brightness permanent light.
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The electronics may be programmed to switch to bright flashing mode at low voltage and low rpm/speed before the full charge at normal operating voltage and high rpm.
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Is this crank usable or should it be replaced? I've been suffering from weird noises while pedalling for a couple of weeks. Noise has been isolated to the left foot, its definitely not the right side. After an inspection revealed no cracks or other badness, I pulled the left crank off with a puller. The lip around the presser on the right hand side of the image? That's compressed outward, and once I got the crank off the pusher of the puller was wedged in the taper. The other two sides are only lightly marked. The two sides pictured are the worst damage. The crank was cleaned and refitted with a light coating of copper slip on the facing surfaces and it seems to be functioning fine. But Question : Is this crank safe? Or is it vulnerable to further damage? <Q> It's hard to tell if it will be OK, and it will depend on how heavy you are and how much pedaling torque you can produce. <S> The main problem you are going to face is not the reduction in area of the taper surface, but that the puller will have pushed the edges of the gouged area up, so that the crank will not fit quite properly on the spindle taper. <S> Because of this you may find that you have problems with the crank staying on the spindle. <S> If you feel inside the taper with a finger tip (my pinkie fits inside a crank taper, and I have fairly big hands) <S> you will feel an raised edge or 'burr' of material around the gouged area. <S> You will want to very carefully file that off with a fine, flat needle file. <S> It will only take a few light strokes to remove it. <S> When you re-install the crank, torque the retaining bolt up to the maximum allowed. <S> Do a test ride and check that the crank is staying in place. <S> Check the crank regularly when you ride after that. <S> Hopefully it will stay in place. <A> The damage shown is unlikely to cause a structural problem. <S> Once you reassemble, torquing the arm on very tightly, you should feel no wiggle of either crank arm relative to the other one. <S> If, after some riding, you find some wiggle, torque the arms on more (within spec). <S> As long as there is no wiggle, the damage will not cause any problems. <S> There is not enough alloy missing to weaken, just to potentially maladjust the tapered fit. <S> The noise you were hearing could have been any of a number of things: a loose crank arm (fairly unlikely if you hadn't removed it recently), a pedal, or the bottom bracket. <S> Check the pedals first -- they should turn freely and without grinding or noise. <S> Service or replace the pedals if not. <S> If the pedals are ok, then test the bottom bracket. <S> Since you have the crank arms off, make sure that the spindle turns freely and without grinding or noise. <S> Also check that it does not have any play by trying to wiggle it up and down or front and back. <S> If there is noise, binding, or play, service the bottom bracket. <S> In the future, use a crank puller with a smaller push surface. <S> Alternatively, you can loosen the screw in the crank <S> spindle a few turns without removing it and have the puller push on that. <S> That will extend the spindle enough to prevent the pushing surface from going into the tapered opening in the crank arm. <A> It may or may not be ok if you tighten the crank down really hard. <S> I had a similar experience <S> so I overtightened the crank to prevent it from making noise, but I ended up damaging the bottom bracket even though it is a much harder material.
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If that screw head prevents the puller from threading into the crank arm far enough, you can put a screw with a smaller head into the spindle and push on that.
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Effect of drinking coffee before riding? I'm 173 cm with about 45 kg weight (underweight). In the same ride of 30 km with short but steep uphill and downhill, if I drink coffee I tend to feel better when riding, but about two hours after the ride I would feel weak and shaking. Note that I drink about 150 ml moccachino. I don't feel like this if I don't drink coffee.Is there an explanation to this? Am I maybe intolerance of coffee? Maybe I don't eat enough? Personally I don't really enjoy the taste of anything other than moccachino. <Q> A recent documentary on the BBC in UK covered some aspects of ingesting caffeine prior to exercise. <S> A written summary is here: http://www.bbc.co.uk/programmes/articles/23hqLh1TYQqZdql7GkqQZ1L/which-types-of-exercise-benefit-from-caffeine <S> Without reviewing the science in detail, it basically suggests that for endurance type activities, caffeine blocks receptors in the body, leading the brain to "perceive" less pain and fatigue, allowing someone to exercise longer. <S> The article states an optimum amount of caffeine to be 3mg per kilo of bodyweight (somewhere between 1 and 2 large cups of filter coffee for average man / woman). <S> To experience the benefit you should drink the coffee approximately one hour before starting the activity, and the effect will last for "a few hours". <S> If you regularly drink a lot of coffee (or take other sources of caffeine), it is likely the impact will be reduced. <S> Of course, other factors may be causing your fatigue, but your question specifically asked about effects of coffee / caffeine. <A> 2 hours is about how long your body has glycogen stores for. <S> So you're bonking because your body has used all the available glycogen. <S> The caffeine will be making fats easier to process instead of glycogen, theoretically leaving you with more "on-tap" at the end of your ride. <S> But you are a scrawny wee twig and lacking in mass, so for you there is less fat available, and the bonk wall will be steep and and immediate, a figurative wall. <S> Your solution is to eat more while riding. <S> Start with a gel <S> every <S> ~30 minutes and see how you feel at the 2 hour mark. <S> Gels are basically easily-digested sugar slop with some flavour. <S> If you don't like gels, then try a square of chocolate. <S> Break it up and freeze it overnight, and store it in a top tube bag or somewhere else not directly on your person. <S> Chocolate is also a significant component of your drink, making it a good substitute that can go with you on the bike. <S> A moccachino is 2/3 cocoa and milk, with an espresso shot, topped with milk foam and dusted with powdered chocolate and optional chocolate syrup. <A> I suggest taking a break from caffeine before riding for 2 weeks to reset the body and see how you cope with your normal mileage
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Your experience may just be the effect of the coffee / caffeine wearing off, plus any lessened impact due to the amount of caffeine you ingest on a daily basis.
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Hit by a car bent rim I have a new 199.99 Schwinn I got from Wal-Mart a few months ago. Just the other day, a lady didn't stop for me and knocked me off my bike. The front wheel was stuck under her SUV, rest of the bike is fine. Now, it's still rideable but has a bent rim that wobbles when I ride. Is there a way to repair by straightening it rather then replacing it? <Q> It depends on how much the rim is bent, and if the deformation is lateral (side-to-side) or radial (in the direction of the spokes). <S> Take the wheel to a bike repair shop and get it evaluated. <S> The shop may be able to true it. <S> If it's not repairable they should be able to recommend a replacement. <A> When a metal is bent, it means it has undergone plastic deformation. <S> Even though it might be brought back to the original shape, its mechanical properties with respect to impact absorption are severely degraded. <S> The only way to restore the integrity of a plasticized metal is to use a thermal treatment known as annealing (heat it above a certain temperature, keep it for a certain time, cool it down slowly), which is going to cost more than a new rim. <S> Considering how critical is the wheel for your safety and the fact <S> you say the wheel wobbles, I would replace the rim. <A> But if you're stuck with paying, I'd ask around at your LBS and/or look on Craigslist to get a used replacement. <S> You'll likely be able to find what you're looking for, and you'll certainly save some money if you find one.
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As a safety precaution, don't ride the bike in the meantime. I agree that if the driver was at fault, she should be paying for a new wheel.
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What photos should I include in an ad of a bike? Now and then I have to sell a bike on an internet marketplace (e.g. Craigslist, Facebook). What type of photos should I include in the posting to convey useful information to potential buyers? <Q> Short version: As many as you can. <S> Slightly longer version <S> :I always include an overall photo from drive-train and non-drive-train side. <S> In addition to that one of the cockpit and close ups of the drivetrain and brakes. <S> That should include most parts of interest. <A> Bike perpendicular to the camera view and centered in the shot <S> Well lit Against a plain, light colored background without any thing else in the picture High resolution <S> Depending on the bike, a single good drive side photo can suffice. <S> As @nollak says: including good, well lit close up pictures of parts of interest to highlight higher end components, good condition, lack of wear etc. <S> is a good idea. <S> As @Grigory Rechistov says, pics of minor cosmetic damage you want to 'own up to' help to depict you as an honest seller. <A> Also, being able to see the pad-to-rim contact is great, too. Front and rear deraileurs, and with..... .... <S> A shot down the top and bottom of the chain in highest and lowest gears to show alignment, photos edited into one, but with high-quality so that zooming in doesn't ruin the photo quality too much. <S> Seat and handlebars, including particular emphasis on the shifters and brake levers. <S> Front and rear hubs, showing if any grease is splurging out or if it's nicely set up, and so if any rubber seals are present, their condition is visible. <S> Chainstay for any damage from chain slap. <S> A birds-eye view shot of the whole bike. <S> A drive-side view shot of the whole bike. <S> Front shot of the bike to show the cabling routing from the front; If it's ugly or unsuitable, we want to know about it. <S> No dirty living-rooms or unmade beds in the background, please. <S> Also, please don't put your workshop/garage in shot as almost every photo of a bike with their garage shot in has a horrific mess that, if anything, merely sets off my OCD and makes me not want to look at all.... < /RANT>) <S> It's also handy if you take a photo of the whole bike, and show what products you use on the bike for maintenance (Lubricants, degreasers, cleaners, etc) so that people can see how the bike is maintained. <S> Hardly essential, as a good bike will show in the pictures, but seeing what's used is good reassurance to a prospective buyer. <S> If you're just putting an ad up for a really cheap bike that you want to get rid of, just include the Main 7: Brakes Front Brakes Rear Gears Front Gears Rear Drive Side Non-Drive Side <S> Front <S> Good luck with the sale, <S> and I hope you get a fair price for both parties. <S> :)
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When I take photos of my bike, I particularly focus on the following: Front and rear brakes, showing the pad thickness as well as alignment with the wheel and forks to show set-up of the pads. A non-drive-side view shot of the whole bike. However, it's vital that if you take ANY photographs, they need to be of decent quality, have to have good lighting - preferably cold-white LEDs or daylight is even better- and background ( In case of suspension photos of the sliding surface of fork and damper could be of intereset for potential buyers. You should have at least a good quality drive side picture:
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Skidding/skipping a fixie with ratio 48/16 I'm a noob. I have a single speed with 48/16 ratio with flip-flop wheel. I wanted to try what is a fixie and installed pedal straps. I tried to lock a rear wheel, but it just pushing my hard and keep spinning. I don't see how I can stop it :( I guess it may be related to ratio/speed/surface. What is the minimal advised ratio for a fixie?Advises are welcomed. <Q> The less weight on the wheel the easier it will be to skid. <S> Lean forward (BE CAREFUL) and then try to lock your legs, think about where your legs are the strongest and try there. <S> Many people also do "hop skids" where you hop your rear wheel (lift it off the ground) and lock it while it is in the air, then return it to the ground while it is locked. <S> 48/16 isn't a bad ratio (pretty normal). <S> you don't wan to dictate your ratio based on your skidding, you want it to be based off your riding cadence. <A> I'd suggest thinking less about 'locking your legs', and instead think more about pressing down hard with your trailing leg. <S> I find that if I put too much effort into pulling up my leading leg <S> I end up pulling the muscles in my groin. <S> You'll still need to pull up a little and lean over the front to initiate the skid, but focus on the push to make it easier on your legs. <S> Also, practicing in the wet makes it much easier to get the rear wheel to slide. <S> Anyway, install a front brake for when someone pulls out on you or jumps out from the pavement so you can stop it quickly, and practice skid stops in more controlled environments first :) <A> Using a fixed gear develops muscles that you don't normally use on a geared bicycle. <S> It'll take time for your body to get used to using those muscles and until then skidding will be difficult. <S> First focus on hopping the rear wheel. <S> When you're comfortable doing that, hop the wheel and then hold your legs in place on the landing to get a short skid. <S> When you're used to that you can practice shifting your weight forward ("unweighting" the rear wheel) and dragging the skid out further. <S> You must make sure your feet are in the correct position - they'll be relatively flat horizontal to the ground. <S> Also be aware that skidding ruins tires quickly. <S> I commute using a fixed gear <S> and I scrupulously avoid skidding. <S> I can stop as quickly or even faster by keeping my weight back on the rear wheel and using my leg muscles to slow down. <S> That being said, being able to skid is a practical skill - a short "hockey" skid has saved my ass at least once from getting creamed by a car.
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the easiest way to start learning how to lock your legs correctly is to alleviate weight to rear wheel.
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Mountain front derailleur for braze-on mount? I'm converting a Giant 2006 carbon road bike to flat bars. It has this setup: Ultegra 6600 Triple, braze-on mount, bottom-pull, 52/39/30 105 5600 10-speed, 12-27 I have a set of SLX M670 10-speed shifters I'd like to use. The cable pull is (apparently) wrong on both ends, so I'm looking for replacement derailleurs. What front derailleur can I use with these shifters that'll work with a braze-on mount? It's not clear to me which, if any, Dyna-sys derailleurs fit this frame. Or if any of them can handle the 52T ring. The fallback is to give up and buy a set Shimano R770(?)/R780 or Microshift TS83-10. Microshift and R780 seem most likely to be compatible, but there's not a lot of documentation on the former. <Q> Have you considered cable pull adapter that would allow you use both MTB shifter and present road front derailleur? <S> Jtek Shiftmate 7 seems to do what you need. <S> I have not used any such adapters myself yet <S> but I thought you should need about such possibility. <A> First, no MTB braze-on front derailleurs are currently made, and certainly none with the capacity to handle a 52/36t shift. <S> Second, your backup plan is the correct path. <S> I have no hands on experience with the microshift shifters, but the SHIMANO Tiagra 4703 flat bar triple shifters, or <S> the R770/780 sets are what you need. <S> Either will work, and the Tiagra are cheaper and more readily available in my experience. <S> Documentation can be found at http://si.shimano.com <A> This turned out to be complicated enough to merit another post. <S> There is no 10S MTB ("Dyna-sys") <S> front derailleur with a braze-on mount <S> , so I've listed Shimano-compatible flat-bar road shifters. <S> http://blog.artscyclery.com/science-behind-the-magic/science-behind-the-magic-drivetrain-compatibility/ <S> http://productinfo.shimano.com/download/pdf/com/3.0/en <S> These shifters will work with 10S Shimano road RDs, except for 4700: <S> Shimano R460 <S> | 2x10 <S> Shimano R780 | 2x10 <S> Shimano R783 | 3x10 <S> Shimano 4600 <S> | 2x10 <S> Shimano 4603 <S> | 3x10 Microshift TS83-10 <S> | 2/3x10 <S> Microshift R760-2 <S> | 2x10 <S> Microshift R760-3 <S> | 3x10 <S> These shifters will work with 11S Shimano road RDs: Shimano RS700 <S> | 2x11 <S> Shimano U5000 <S> | 2x11 <S> Microshift R860 | 2x10 Microshift R761 | 2x11 <S> This shifter set works with a 4703 (and probably 4603) FD and a 4700 RD. <S> Shimano 4703 <S> | 3x10 <S> This shifter set works with a 4700 FD and 4700 RD: <S> Shimano 4700 | 2x10 <S> These shifters work with a 9S Shimano FD and a 10S Shimano road RD, excluding 4700: <S> Shimano R770 | <S> 2x10 <S> Shimano R773 | 3x10
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Get a road flat bar shifter set.
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Can I use Rockshox tokens with my Sektor fork? (Fuel EX 5) I would like to experiment with ramp control with tokens but I cannot find out if my fork is compatible with the regular Rockshox tokens, is it too low end?? Thanks. <Q> The Sektor fork does not appear to have a compatible token. <S> From the Rockshox web site https://www.sram.com/rockshox/technologies/bottomless-tokens : <S> Grey bottomless tokens are compatible with the following Solo Air forks: Pike, Lyrik, Yari, Pike DJ, BoXXer. <S> Dark red bottomless tokens are compatible with the following Dual Position Air forks: Pike, Lyrik, Yari. <A> As far as I know rockshox sektor is just a cheaper version of revalation (motion control damper, no sag indicator etching on right stanchion and no ability to add volume spacers) <S> so you can just swap out the top cap (on the left side) and add volume spacers. <S> Cheers <A> No, the Sektor fork is too small in diameter internally. <S> I‘ve tried but the tokens‘ diameter is too wide to fit inside the bore.
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Black bottomless tokens are compatible with the following Solo Air forks: RS-1, SID, Reba, Bluto, Revelation.
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Seat post slipping down It looks like my saddle/seatpost is slowly sliding down into the frame, so every 2–3 months I have to move it up by 1–2cm. Yet I tighten the clamp pretty tight, so I can't move the saddle by hand. Is this a common thing? Should I fix something? I weigh about 55kg and cycle on the road, about 50km per week. I try to lift my weight off the saddle over bumps. The bike's a hardtail. <Q> It may seam counter-intuitive, but in the case like you describe a little grease may be the solution. <S> NOTE: <S> If you have a carbon frame or seat-post, carbon specific grease and a torque wrench should be used. <S> It's very easy to destroy a carbon frame or post by over-tightening when installing parts. <S> Remove the seat post and clean it and the inside of the frame thoroughly with a little degreaser. <S> Remove the seat post clamp if it has one (some frames have braze-ons through which the seat bolt is installed rather than a separate clamp) and clean the inside of the clamp and the outside of the frame. <S> Apply a very thin coat of teflon or lithium grease to inside of the clamp, and to the threads of the clamp bolt. <S> I generally do not apply any grease to the outside of the frame. <S> Apply a very thin coat of teflon or lithium grease to the seat post and the inside of the seat tube - just enough to facilitate installation and inhibit corrosion. <S> Install the post and adjust the height. <S> Tighten the clamp to the manufacturers specification. <S> The cleaning should remove any grit or dirt that may have been working like tiny ball-bearings and allowing the post to slip. <S> The small amount of grease on the clamp, frame and post should allow the parts to constrict and tighten evenly with out binding in one particular spot. <S> If, after cleaning, lubricating and reinstalling you still have a post that slips you may have a frame that has deformed, or a post that is slightly smaller in diameter than spec. <S> You can try either replacing the collar/clamp with one that is a little "beefier" that can be tightened to a higher torque, or you use a shim like a piece of thin aluminum between the frame and the post. <A> Ideally, the first thing to check is how good the fit is, or in other words whether tolerances are causing or contributing to the problem despite the nominal sizes matching. <S> That way you have a better sense of what you're up against. <S> If the post has a lot of slop with the collar loose, it's possible nothing will make it work, although that's an outlier. <S> Now that carbon grip is an everyday item <S> , there's no reason not to use it in slipping post situations regardless of material. <S> So start by cleaning everything, putting a generous amount of that on the post/frame interface, and making sure all the mating surfaces of the collar and bolt are clean and greased. <S> That's about as much as you can do without changing parts. <S> If that doesn't work and it's a bolt-down collar as opposed to QR, the first thing to look at is how beefy the collar is, if applicable. <S> The thicker and heavier, the harder it pinches the post and the less it itself flexes as the bolt is torqued. <S> Slippage happening due to tolerances on frames with collar type clamps can often be obliterated by just putting on a stiffer collar. <S> If it's a QR collar, there are some bad ones of those in the world, and they can get worn/mangled with repeated hard re-tightening, so replacing them can be necessary. <S> Bolt down ones clamp harder in general too, so if you don't care about QR then that can make sense. <S> (The average case scenario of a slipping post in shops is it's a junky QR collar, and the fix is replace it with a bolt down one and slather with carbon grip. <S> Usually fixes everything.) <S> Sometimes the seattube opening needs some reworking too. <A> Some stock seatpost clamps just do a poor job, too skimpy due to the manufacturer wanting to save a few bucks or a few ounces - I had a problem with the seatpost slipping on my otherwise excellent hybrid cruiser. <S> Beefy and strong generic aftermarket alloy seatpost clamps are a common upgrade, $7 USD or so on Amazon or Ebay in a variety of colors for metal frames, $20 USD if you want a name brand component compatible with carbon frames/posts.
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If it's an integral clamp, or none of the above fixes it, and it's not an undersize post, then some of the more advanced, shop-tool-requiring fixes can come into play, such as reaming the seattube or knurling the post.
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Which kind of bicycles is better and comfortable for shorter communtes, 4-5 km daily This kind straight handles or this kind? <Q> My priorities: Right size for you. <S> A must . <S> Light weight as possible/desired Low price - it needs to be do a simple job without being a thief magnet (at least here) <A> The difference between handlebars, or in general body postures on bicycle, starts to show itself at distances of 50 km. <S> For 5 kilometers a day, which I assume consist of two intervals of 2.5 km each (to work and back), it really does not matter. <A> One style of flat handlebar is not absolutely better than another. <S> You should test ride some bikes and see what you personally prefer. <S> Bicycle stores offer test rides in the USA, but I realize it might not be the case where you live.
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I would say gearing would play more difference than type of bike.
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Please help me identify the specifics on my older Giant Sedona? I was generously given this working, older Giant Sedona. I have searched and searched, high and low to find out specifics on the bike, to no avail. I've been to Giant Bicycles website, there's no info available about older bikes and you can't register an older bike either. I have been to Bikepedia, again no specifics about my bike. bikeindex.org, it was never registered there as stolen. I have google searched "giant sedona" and have looked at images for hours trying to identify specifics on my bike. I have spent hours reading links and pages and pages of posts about identifying bikes. It would be neat if Giant or someone would create a site that one could plug in the serial number and find info about a specific bike. I'm surprised no one has done that yet. Nonetheless, if anyone has any useful tips I'd appreciate it. Thank you. <Q> This is a 1996 Giant Sedona. <S> I had this exact bike, right down to the color. <S> If you notice the top tube and down tube are flared at the joints. <S> The was the 'external butting' and they were also butted for tube wall thickness internally. <S> The groupset was entirely shimano STX, which, at the price point (about $600 CAD at the time) represented an amazing value. <A> I can see a sticker on the seat tube - which might be the Giant size sticker but if it is a bike shop sticker you can call them and there is a chance they will have the serial number <S> In terms of registries that is a no-go. <S> There is no single national bike registry. <S> It varies by geographic region or jurisdiction, most places going away from registering bicycles in the nineties or earlier. <S> Giant buys the rest of everything else from a third party - especially things like wheels and shifters are made by Shimano, and a bunch of other wheel makers. <S> its not a bad bike, its an inexpensive one, that any shop will know how to work on. <S> I would just appreciate the working wheels <A> There were cooler paint jobs on versions like the ATX. <S> After that in the late 90s the started offering forks with shocks. <S> What are the specifics that you are looking for? <S> You should be able to identify the components by sight and markings. <S> count your gears. <S> Wheels look pretty basic 26", tires the same.
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7 speed rapid-fire shifters, panaracer smoke and dart tires, non descript black quill stem, giant branded aluminum bar, saddle and grips (which were thin and hard, but after a while I got so used to them that any other grips felt mushy).I can't recall the rim manufacturer and model, but they were 36 spoke....a great bike, and if you still have it, I'd be tempted to offer to buy it, strictly for nostalgic purposes.... This is a early 90s, maybe 1992 Giant Sedona Base model. The frame is 4130 cro mo and the tubes are 'triple butted'. The other thing is about the only thing a bicycle "manufacturer" builds is the frame. In the later 90's they moved to having shock absorbing seat posts, and different styles of brakes. That being said as far as specs I can tell you that you most likely dont have a lot of the original parts on this frame.
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How to re-terminate frayed brake cables? I've bought and installed new cables for my bicycle, but I didn't have any cable-ends to crimp the ends. I've been riding for a few days now and just noticed that one of my cable ends has unwound itself due to movement or vibrations. Now I have a frayed set of wires sticking out of the end of my brake calipers. Is there a good or proper way to reset these wires back to their original position so that I can crimp the end of the cable properly? Thanks <Q> Seth's Bike Hacks channel on Youtube has a video that specifically addresses this problem: <S> A quote: <S> When I showed the cable fray trick in another video, some of you thought I was playing it in reverse, but it’s true! <S> You can unfray some cables by twisting them from the base and working your way back up. <S> This works particularly well on cables that were recently frayed, and usually by clipping a little off the end and adding a new cap, you’re back up and running without needing to swap the whole thing. <A> You can just try to do it by hand first, then use pliers to twist the cable back into place. <S> That is what has worked for me. <A> I twist them back together, then if its my bike will thread a length of heatshrink over the wire and contract it with a hot air gun. <S> Then I nip off the very end with my cable cutters. <S> I've also used flux and solder to join the frayed <S> ends together once they were retwisted. <S> That was a sleek-looking fix (more aero too!) <S> Putting a crimp cap on works too - do be careful to capture all the metal threads because they're no fun later.
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If that fails, cut off the cable to a point where you can twist it back.
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Rental bike for holiday: wise to change handlebar style? For my next cycling vacation I am evaluating the possibility to locally renting a bike instead of taking mine along: the costs are equivalents and I would save the hassle of carrying the box around. The rental services I am exploring offer either city/touring bikes with flat bars or cyclocross/road bikes with drop down bars, while I normally ride on flat bar. Is it advisable to keep the same bar style on the rental bike, or "muscle memory" and other stuff will not be a problem? I'd gladly avoid settling problems while riding 100+ km/day. Additional info : I am looking to cycling in Japan, Biwa lake and Koyasan. Therefore paved roads but hilly, not really away from civilization, but still with some roads among the mountains. <Q> I'd recommend getting used to a new handlebar style (or frame geometry or any other change) slowly. <S> On a multi-day trip problems tend to accumulate, so I would't recommend trying anything new. <S> An additional problem with drop bars is that the brake and shift levers work differently and some people seem to have problems getting used to them. <S> You could try to rent a bike with drop bars at home and see how it works out. <S> Edit: For the kind of trip you are planning, many cyclists prefer drop bars. <S> I would recommend trying out them if possible. <A> Most countries drive on the right (including probably yours, but not mine). <S> In Japan they drive on the left. <S> Driving etiquette is also very different in Japan (we've had questions here about some aspects that affect cycling and are non-obvious). <S> Unfamiliar bars (brake location, lower head position affecting your view) and unfamiliar traffic habits aren't a good combination. <S> I've also found the fit on flat bars to be more forgiving (get the saddle height right <S> and I can jump on and ride for a few hours). <S> Even though my tourer is a very good fit it still took some getting used to at first <S> and I'm not sure a multi-day trip is the time to do that. <S> Your back could well suffer. <A> Drop handlebars give a rather different riding position to flat bars. <S> They tend to be narrower (much narrower if you cycle on the tops), farther forwards (if you're using the hoods) and lower (if you're on the drops, but probably on the hoods, too). <S> If you're not used to riding in that position, 100km per day is going to be very hard work. <S> It'll probably hurt your back and also your neck from having to bend it more to see where you're going. <S> I recommend sticking with what you're used to. <S> Enjoy your holiday on a bike like the one you ride at home. <S> If you want to start riding with drop bars, do that on time that (a) you're not paying for and (b) you don't have huge <S> "This is going to be the awesomest week!" <S> expectations for. <A> You haven't mentioned what a "cycling vacation" is for you: Is it a four-day wine tour in France, or is it a month-long trek across Kazakhstan? <S> You mention "100+ km/day", which implies a decent pace, but it still leaves the riding style open as to how often you take breaks, how tough the terrain is, etc. <S> Easy/short/safe rides <S> The closer you are to civilization and the more frequently you take breaks, the less important the actual handlebar choice is: If it's not comfortable or you don't feel confident using them, take it slow, take more breaks, etc. <S> If you really don't like them, spend an extra day relaxing in some nice town and cut your trip a bit short. <S> The cost of changing out handlebars in terms of money, time and hassle just may not be worth it. <S> Hardcore tours <S> On the other hand, if you're going to be in the middle of nowhere and absolutely have to e.g. get across those mountains and to a specific village by nightfall <S> or else you're in big trouble, the costs of using a new handlebar style may be more critical. <S> In fact, if this is the type of tour you're envisaging, the "cost" of renting and riding a bike you're not used to (and possibly don't trust) may be higher than the cost of bringing your own bike along.
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Drop bars may be more aerodynamic, but not by enough to make up for a bad geometry you can't adjust in the field, and if you're touring with a slow group, being able to blast round and get off the bike sooner isn't much help. I'd stick with what you're used to.
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How can I fit a bigger rear tyre when limited by the front derailleur? I've recently bought a hardtail, just an entry-level bike, but I've only got entry-level skills. The tyres it came with are WTB Nano 2.1". They aren't exactly ideal for the sort of conditions we have in the UK in winter (lots of deep mud, wet tree roots, muddy rocks etc.) and I'd like to fit something (i) knobblier and (ii) a little wider. At the front this is easy, something like a Maxxis Shorty 2.3" or Magic Mary would easily fit. At the back, there's also plenty of room except behind the front derailleur where there's about 3 mm (and that filled up with mud today) There are 2" tyres for mud, but they're reputed to have a harsh ride on anything else, and not grip well on wet rock/tree roots -- something I need at my skill level as my lines aren't up to much and I don't always carry enough speed. This is the only bike I've owned with a top-pull FD. And I can see why they've used one rather than have cables under the BB getting coated in mud and even bashed. But it takes up much more room than any of the bottom-pull FD's I've got. Is it because it's a cheap FD? Because it's a triple? It's an Altus 3×9 drivetrain. Is there an upgrade that would gain me a few mm? As an aside: I picked it up in a hurry, lightly used/ex-rental and without a test ride, for around half the shop price. I'm happy with it apart from this, and assumed that I might upgrade consumables (perhaps as they wear out). I looked at the specs in detail to be sure the fundamentals were there, but is there any way I could have spotted this? <Q> Easy and cheap option - remove FD (change chain ring by hand if needed). <S> Put it back on for summer riding. <S> More expensive - Go to a full 1x - cost <S> is the only limiting factor <S> As its disk brakes, you could install a 27.5" rear wheel with a small change to bike geometry (this will help if chain stay clearance is too small on 29" rim). <S> In all honesty, I suspect your fighting a loosing battle where you will waste a lot of money on a compromise. <S> Be careful listening to the advice of 'expert's who ride $5K bikes, its easy to criticize and suggest improvements when its not your money. <A> Put a larger tire on the front and don't worry about running a larger tire on the rear. <S> Back when North Shore BC riding was just starting to take off (i.e., 1990s) we often did this setup as we were equipment limited. <S> At the time the "thinking" was that it was bizarre ride a tire bigger than a 2.0 anything but a dedicated race downhill bike. <S> So we would often swap a fork and run bigger rubber up front as there was clearance issues in the rear. <S> Now 25 years later and anything less than 2.3 is pretty much considered anemic for most riding. <S> Anyway, the mismatch tire size works fine. <S> The front is where you are often traction limited as you brake and steer with this tire. <S> A small rear tire may mean a bit harsher ride <S> (i.e., higher pressure with all other things equal) and a tad less traction, but you can afford this compromise on the rear. <A> There are several options that stem from the idea "Something cannot hinder you if it is not there", namely the FD. <S> Specifically, you can go the ways of 1x or single speed. <S> Both variants assume you remove all the machinery related to the front shifting (== bonus weight savings!) and leave the single front chainring. <S> For MTB applications the lowest teeth count you can have on the alivio spider is most likely 32t, and that is what I recommend. <S> The rear derailleur you have is not optimal for achieving a wide ratio range, as 9 speed cassettes are not that wide and will never be. <S> Now even a 10 speed Shimano deore cassette can be had with range 11-42 teeth, and that is just fine for a casual off road adventurer. <S> One can choose to throw all this gearing bullshit away and go boldly with single speed. <S> Rear hub conversion kits (a cog, cassette spacers and a chain tensioner) are cheap. <S> More weight savings, no thought power wasted on choosing the right gearing because you are always in the wrong gear, and more fun on descents. <S> On climbs, not so much. <S> Another crazy idea is to cut some knobs of the rear tyre. <S> There are in fact MTB tyres that are meant to be trimmed by users to their liking, and dedicated tools to do that. <S> The drawback is obviously losing some traction in situations when the removed knobs would have been working. <S> Finally, moving the rear wheel farther back would be the easiest solution. <S> This is what I actually resorted to when I faced the same issue on my fatbike, because its frame was designed as a multipurpose one. <S> But it requires sliding rear dropouts, which are not super common on MTBs with derailleurs.
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An eccentric rear hub would also do, but I am unaware if there are any designed for non single speed systems. Plus, one tire is cheaper than two, and if any one asks just tell them the setup is more aero (#AeroIsEverything - /sarcasm). With 9 speeds (11-34 teeth range) in the back and 32 teeth at the front, one might sometimes feel out of range, but even this setup might be fine on flatter terrains.
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Magura rim brake does not work well on a new rim I have a bike with 20inch wheels and Magura HS11 rim brakes . On the rear wheel I have just replaced the rim, because the old one had split after many thousand kilometres. The new rim is an Alex DM24 406X24 . The old one was another wide aluminium rim. The Maguras were braking fine with the old rim. In contrast now with the new rim the brakes do not work well: After some initial moderate stopping power the brakes do not grip harder when I pull the lever harder. To explain it a bit more in detail: When I press the lever slightly (say, of a “feels-like’ amount of 10%) the brake reacts as expect by braking of “10%”. But when I press hard, say 50% or 100% (=as hard as I can), the breaking power does not increase at all, it stays at around 10%. I am pretty sure it is not an issue with the brake system (oil, etc), because when pulling the lever I feel that the pressure against the rim increases. (Furthermore, not oil is leaking out and the brake behaviour is consistent over days.) I guess it must have to do with the brake pads an the rim surface. The rim looks to me like it has normal alloy sides, so I kept using the old black brake pads. So, what might cause this strange behaviour? Should I replace the pads with pads of another type? Or is there another fix? <Q> As it turned out, the problem were not the brake pads. <S> The issue was cause by the fact that the new rim is slightly narrower. <S> The brake cylinders still touched the rim, but were the already nearly fully extended out. <S> This lead to the particular situation that the brake started breaking lightly, but full force coupled not build up, because the two cylinders had reached their maximum extension before that. <S> The fix was easy: I moved the brake cylinders (in the released position) further in <S> and now they are gripping the rim again properly. <A> You need to bed-in them. <S> Additionally, because you've changed the rim it is possible that pads need re-alignment as they do not fully engage with the new rim's surface. <S> Watch closely if they contact the braking surface at the right angle from both sides, do that with their full width, and that they avoid touching the tire. <A> Magura rim brakes were/are known as "rim-crushers" because they were capable of putting out a lot more pressure than the caliper brakes of the day. <S> I had them on a tandem <S> and I could lift the rear wheel with the front brake, when riding it solo. <S> So pressure is unlikely to be the problem. <S> I'd take the wheel out and have a close look at the brake pads <S> - I bet they've got a layer of something that has rubbed off the rim. <S> Probably unmount the tube and tyre first, and left the rim stand for a few hours after cleaning and before reassembling. <S> Last resort before replacing the pads is to see if they will swap left for right. <S> That way the edge that meets the rim will be clean or cleaner than the other end. <S> Magura pads come in 4 colours <S> Black - Standard pads suitable for all rims offering good performance and good wear in most conditions. <S> Grey - Standard pads designed to work better on anodised(hard-coated) or ceramic coated rims offering good wear in most conditions. <S> Kool stop (Red) <S> - Performance pads for all polished/uncoated aluminium rims offering greater stopping power particularly in dry conditions. <S> Green Frog - Performance pads for all hard anodized(black) and ceramic rims offering greater stopping power particularly in wet conditions. <S> So for dull aluminium brake tracks use RED and for ceramics and shiny aluminium use GREEN.
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It is expected that new braking rim surfaces, brake disks and pads are less efficient in the beginning. You could clean off the braking track using Isopropyl alcohol and clean tissues.
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My bike goes up one gear at a time, but down two: is this normal? Just over a year ago I bought a new bike (a Giant Escape 3) with a trigger gear system - my previous one had a grip-twist to change gears. After riding and experimenting for a while, I was able to determine that the trigger down didn't shift a single gear - it changed down two. This behaviour is consistent as far as I can tell: it does it every single time I've thought to check, whatever gear I'm in. The trigger up does increment a single gear as expected. It's just something I've learned to ride with: it's not entirely inconvenient in traffic when you're stopping frequently at lights. But lately, I got to wondering whether it was, in fact, a "feature" or a "bug"? If it is a fault, how can I fix it? <Q> On or off road, but especially off road, it is desirable to be able to shift down more than one gear at a time to deal with abrupt changes in gradient and avoid being stuck in too a high a gear and stalling out. <S> Also (as you mentioned) if you are required to slow down or stop suddenly, it's convenient to be able to drop down several gears while simultaneously braking, then be in an appropriately low gear to accelerate back up to speed. <S> Some modern shifters allow downshifts of 4 or 5 gears. <S> Yours may provide 2 with a full stroke of the lever, so the solution may be to simply 'half stroke' the lever to get a single downshift. <S> If you edit your question to add the make and model of shifters and derailleurs you have we may be able to provide a more specific answer (or tell if there is something wrong). <A> Both shifters have the same User Manual which has this information on downshifting: <S> Assuming you are talking about your rear derailleur (right shifter), to shift 1 position you need to push the lever a small amount. <S> Pushing the lever more will cause it to shift 2 positions (and depending on the type you have, pushing further will cause it to shift 3 positions). <A> I have a Giant Escape 3, although is is a few years older than yours. <S> I think this behavior is normal for trigger-shifters. <S> When shifting into a higher/harder/faster gear (on the rear) you use your index finger and it will shift one gear at a time. <S> When shifting to a lower/easier/slower gear you use your thumb. <S> If you push until you hear a single click it should shift one gear. <S> If you keep pushing it will click up to three times and shift up to three gears. <S> Is this what you are describing? <S> This is presumably to allow you to quickly shift down multiple gears when encountering a hill or obstacle. <A> Most likely you have friction in the rear shift system cabling. <S> if the derailleur cable is frayed or dirty or if any of the cable housing is bent you can have the shifting not work the same in both directions. <S> Inspect all of the housing and cable. <S> Look at the housing where it goes into the derailleur in particular - this is a tight bend. <S> Lube the cable with a light weight oil like triflow. <S> There is a trick you can do if you have slotted cable housing stops. <S> Shift into the lowest gear and then shift back to the highest gear without pedaling to free up cable and allow you to slide the housing out of the stops and lube the cable. <A> I am not sure what is happening actually. <S> If you change the gear index by one and chain goes two <S> it is a problem. <S> Usually caused by misaligned derailleur - you are, say, in 3.9 position and change to 2.4, index shows 3 and 2, respectively, but the chain aligns to 4th and changes to 2nd gear. <S> If you are able to change indexes not only by 1, or by more, per one push, it is not a bug. <S> It is a feature allowing you to downshift much faster when you need downshift fast. <S> If you are able to downshift by 2 gears only, there might be problem, though. <S> Maybe one lever in the mechanism isn't alligned properly and it misses to lock the first position.
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Old lever or twist gear systems allow this fast change by design, indexed system needs "reload" to be able to change. Depending on the year of your Giant Escape 3, it either has Shimano EF40 or EF41 shifters.
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Why shouldn't I care what model/make/year my bicycle is? We often get questions on bicycles.stackexchange about identifying a bicycles manufacturer, model, make, and year. Often these questions are downvoted or closed -- usually with a comment attached to them that it's not necessary to know the exact model/make/year of a bicycle if you want to fix, repair, or ride your bike. Why should owners not care about the model/make/year of their bicycle? Especially when it comes to less expensive bikes (aka BSOs) and BMX bicycles? This is intended as a canonical question that we can point closed questions to. Also cf: How can I tell what year my bike was made? <Q> The problem with the question is not the owner's interest in the answer - it is clearly there. <S> The problem is that the answer has almost no value for the community of this site: most generic bikes are hard to identify to begin with most successful identification will be based on a photo which cannot be used to answer the same question again because questions and answers are centred around searchable text and tags. <S> Hence, they should be banned in my opinion . <A> The latter do not make suitable questions for SE sites and will normally be closed. <S> For the former, fortunately the bicycle industry is fairly standardized (even if there are many and evolving standards), so knowledge of the bike make/model/manufacturer is rarely helpful in determining any maintenance issues and parts requirements. <S> Ultimately the industry is dominated by a few parts manufacturers and a very large number of "Bike manufacturers", who largely build a frame to the standards of the day and attach components. <S> In most cases, a better question that will lead to more practical answers for the community should revolve around the specific problem that needs to be addressed. <S> Photos of areas of a problem are almost always all that is needed to identify what components and work is required. <S> In rare cases its helps to know the bike manufacturer and model as some parts are very specific (e.g. Bottom bracket widths) <S> These are valid "Identify my bike" questions. <A> I think an owner should care more about what generation their bike and groupset are from. <S> I've successfully fitted a 2000's 105 groupset to a 1980s steel 10 speed, mostly because the groupset was moved over complete. <S> Had I been mixing an 80s deraileur with a 2000 shifter, that would have been less successful. <S> So there are two motivations for "what year is it?" <S> questions Compatibility with stuff <S> Thinking of their bike like a car, where the year model is more related to monetary value. <S> So to the asker - you should care more that your bike is Safe to ride Comfortable to ride (fewer aches) <S> Reliable (breaks down less) <S> Functions <S> well (no misshifts etc) ...rather than nailing down what year each part is from.
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In cases of vintage bikes and none traditional bikes, knowing the bike manufacturer/make/model and year can help track down old and obsolete parts, and the real problem is solved by knowing this information. In total, there is too little to gain from answers for the community in the short and in the long run to make them worthwhile. Most questions are based on a need for knowledge about what parts to use or curiosity.
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Can a tire that blew off a rim be safely used on another rim, and under what criteria? I have a set of tires where one of them blew off the rim on my bike after I slightly over-inflated it. I originally asked a question about this here , and there are more details at that link. The tire did not appear to sustain major damage from the blow off, just some mild scuffing where the bead popped out over the rim. When I took both tires off after this, I did notice they're quite loose on my specific rims (easy to remove with hands, no levers required), so that's probably why it happened. I was thinking of posting these online for free, with an explanation of what happened, and ask that whoever takes them just state clearly to me that the know the implications of a tire blow off, they know enough about bikes and tires to determine if the tires will be safe on their bike, and will take responsibility for any subsequent injury or bike damage if the same thing happens to their bike. The tires seem to be in good shape and I think someone who knows bike can determine if it's safe to use them on their bike. I just don't want some noob throwing them on their bike and having the same thing happen while riding, leading to injury, etc. So I have a several part question: Can a tire that blew off one rim be safely used on another rim? If so, are there any special stipulations? 2. Is it OK to give those tires to someone else, assuming I provide a detailed explanation of the blow off issue I had, and ask them to stipulate that they understand the dangers and know how to determine if the tires are a good fit for their particular rims? Or, should I just throw them in the garbage? Feel free to provide your personal opinion on this one, I don't think it has a concrete answer. 3. Assuming I'm clear about the issues as outlined above, are there any legal implications (i.e. liability for me) if someone else has a blow off and injures themselves with tires I provided "as is"? I'm located in Canada. Thanks. <Q> I have a MTB where the tyres can simply be removed by hand once deflated. <S> The tyres are at 50~60 PSI normally. <S> But I can feel that they engage the clincher bead fine when inflated. <S> My guess is that your tyres never hook into the rim properly, and then overinflating found that area of the bead that wasn't fully seated. <S> As for the social side, as long as you clearly advise the recipient that you're giving them away, because they didn't stay seated properly on your rims then its the recipient's choice whether they use them or not. <S> I wouldn't want to see anyone hurt, but they'll be adults and can make their own choices. <S> Just help them to make an informed choice by sharing the history. <A> There are exactly two possible reasons for the blow-out: <S> You misinstalled the tire, so it was so unevenly sitting on the rim that the failing part was way too high on the rim for the bead to make sufficient contact with the rim. <S> It must have been very low at almost all other parts of the rim for this to be possible. <S> If this is the case, well, you may be fine with keeping the tire. <S> Just make sure it's properly seated all the way around the rim after inflating. <S> The bead is weakened. <S> (Due to age, wrong installing/removing, other mistreating, whatever...) <S> If this is the case, don't use that tire anymore. <S> Throw it away. <S> Your tire is one of the most security critical parts of your bike, you don't want them to fail abruptly when going downhill. <S> If your tire is a city/touring bike tire, the first failure mode is next to impossible. <S> I don't know how racing bike or mountain bike tires behave, but the touring bike tires I use are way too stiff to blow out in the first failure mode. <S> And no tire I have ever installed myself ever blew out in that first failure mode. <A> The question is WHY the tire blew off the rim: <S> The tire was poorly installed. <S> This would be the most common reason for such a failure. <S> The tire is simply the wrong size. <S> The tire is a poor fit to the rim. <S> Some manufacturer's tires are a hair large or smaller in inner diameter than "standard", and the same is true of the mating surfaces of rims. <S> Ie, some tire-rim combos are just a poor match. <S> The tire bead failed. <S> This could be due to damage while installing, or it could have "just happened". <S> The rim failed. <S> It's not at all uncommon for a rim to be worn through by rim brakes to the point that the rim side buckles outward. <S> This may or may not be obvious on first inspection of the rim, but should be obvious if you look for it specifically. <S> The tire was simply overpressured. <S> This is unlikely, but can occur when tire fit is poor. <S> There is also the question of whether the tire was damaged in some way when it blew off. <S> Not only may the failure have been due to a failed bead, but also the rubber around the bead may have been damaged, or the tire may have contacted the frame or other parts and been cut before it came to a stop.
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Not only is it possible to install some tires on the wrong diameter rim, but also a tire that is too wide or narrow for the rim may blow off.
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How to avoid hand strain when landing with a road bike? Whenever landing from a bunny-hop or jumping a couple of stairs, my hands strain just above the wrist. How can this be remedied? Things I have tried: Warming up before going out. Position the handlebars, so that the hoods are parallel to the ground, so that my writs are straight. This results in extremely uncomfortable drops position (wrist rotate at an extreme angle if I want to clear the brakes). Staying relaxed on impact. Absorbing as much as possible with the legs. Keeping the wind away from my joints. Things I haven't tried: carbon forks gel gloves lower tire pressure (35x622 tires @ 7bar) landing back tire first Meta: This is no question, whose answer can not be verified quickly. I have upvoted all the answer and will, or will not, accept one as 'best' some day. <Q> I used to experience this when I switched from doing a lot of mountain biking to BMX - you really have to learn precisely how to absorb the impact. <S> I thought I was doing it right until I no longer had a suspension fork. <S> Simply absorbing with your legs isn't all there is to it. <S> What I mean by that is extending your limbs - just like suspension travel on a full suspension bike would extend once airborne. <S> As you land, the bike needs to touch down the front and rear wheel simultaneously, or ever so slightly tail heavy (touch much and it will slap the front down though, and that's no good!) <S> And the moment before impact your should already initiate absorbing the impact; this is the "careful set down" part. <S> As for the absorption part, we're talking 95% in the legs. <S> Get your weight back. <S> The picture below really shows what I mean. <S> If your weight is way back, the front wont impact as hard. <S> Yes, the rider would've landed very tail heavy to absorb the initial impact of a drop of that magnitude, but the point here is shifting your weight back. <S> His hands/arms are not in a position to absorb much of anything, rather, they're a pivot in the suspension system that is his body. <S> Of course, you've always got the disadvantage of the road bike geometry and proper riding position. <S> But, you can also see in the photo how much space is available in the cavity between the rider's body and the frame. <S> There's plenty of space for a road frame in there! <S> Hope <S> this helps you! <A> Sounds like your wrists are taking too much impact. <S> Try placing the bike on the ground rather than slamming it down. <S> Reducing the violence of the landing will help all round. <S> Gloves are a great idea but won't really help much with this. <S> Your hand/hood position might benefit from a review too - I personally have my knuckles quite vertical, and the wrist moves in the direction of the thumb and little finger. <S> At the other end my ankles rotate, after the initial push-off, and only then would I flex my elbows and legs to raise the bike, to gain height. <S> Hand crunches (those squeeze things) might be a good start. <A> Two things: Learn to absorb the impact. <S> Just before the bike hits the ground need to start retracting your hands and feet. <S> Google "youtube street bmx" and see what they do with their bodies when they land to flat ground. <S> Your body should be supported 90% by your feet and 10% by your hands.
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You want to land flat and carefully set the bike down. You might get benefit from doing some hand/forearm exercises too, to increase the control inside the wrists.
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Aluminium rigid fork for winter I'm looking for the bike for winter riding and found this one . It's all good, except for the fork: some people say that aluminum rigid forks can not absorb vibration and therefore are bad for the winter 'cause there's firm snow and ice, which is not smooth at all. So, are they right and I have to look for steel or carbon fork? (I'd really like to use rigid one for the winter) <Q> Presumably you are looking for a cheap bike to ride in harsh winter conditions. <S> The advertised price of 35,960₽ is about US $615 (at the time the question was asked) which would be considered a quite inexpensive bike here. <S> An aluminium fork will be fine, but look for a bike with clearance for bigger tires. <A> I assume you would use the bicycle in the city. <S> It will make even less difference in a deep snow when all terrain features are smoothed by it, and you cycle slower than usual because the ground is more slippery and treacherous. <S> I would definitely go with a rigid fork (no matter what material). <S> In terms of comfort, I would also go with the widest tires possible. <A> Just in case some one will see this question:I've bought an aluminum rigid fork (some no-name brand) and to test how it feels went on an xc race on that bike. <S> There was quite a lot of snow and bumps. <S> As I've expected I was quite fast on the uphills, but slow on descends <S> - I was feeling that there's limit (for bumpy xc trail) <S> somewhere around 30 km/h <S> - if I try to go faster, I immediately loose control over the front wheel. <S> But for the city riding purposes this fork is a great thing <S> , I have no regrets and like the look.
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Your choice or tires is going to make a much bigger difference than a carbon fiber vs aluminum fork. In this case, a suspension fork does not make much comfort difference compared to a rigid one — there are no roots or rock gardens in St Petersburg.
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My folding tire has kinks in it I just bought my first set of tires. They were of the folding type.Even after unfolding and leaving them overnight they still had kinks in the bead. It is a bit unsightly but that isn't the issue. Do the kinks affect the way they should be installed? <Q> This is completely normal for folding tires. <S> They will settle into round shape when they are mounted and inflated for a while. <S> One way to avoid it is to keep the part that is already on the rim tight. <A> Kinks should disappear once the tire is mounted and inflated and the bead is under tension. <A> I got an unused 20" folding tyre that had sat in someone's bag for 10 years. <S> It was seriously zig-zagged when unfolded, but once on the bike it was perfect. <S> Later I suffered a puncture, and on changing the tube I noted the tyre still wanted to zigzag, but its completely unnoticeable on the rim. <S> For peace of mind, you might want to lubricate the rim with water when first fitting, and then half-inflate the tube, and give the whole tyre a good visual inspection before fully inflating. <S> You can also use your thumbs every inch or two around the outside, to push the tyre's sidewall sideways. <S> Any oddness, stop and evaluate. <S> Note that a "pop" is probably just be the bead seating, compared to a herniation where the tyre is bulging out.
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When installing the tires with kinks, they do slip away from rims more often than perfectly round tires. Leave the wheel fully inflated overnight before riding the first time, and check it again before your ride. There's no need to align the kinks to something, or anything like that.
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Flat tire after inflating to max pressure Bought a used mountain bike for mom. The bike wasn't used in quite a while . Mom used it for 3 weeks , tire pressure was ok but it needed some air. So I pumped air in both the tires to max recommended psi on the tire. After sometime , both the tires were flat. I did not hear any sound of leaking air right after I pumped it. I tried it again, this time I heard a hissing air leaking sound. What could have happened ?Not sure if anything in the valve is stuck.How can I determine what is wrong ? Thanks in advance. <Q> When in doubt, it's much easier to just completely replace the inner tube. <S> They are consumable (like brake pads) and will only cost you a couple of pounds/dollars. <S> This can be annoying and tricky at first but after a few tries should only take 5-10 minutes or so. <S> In my opinion, it's easier and quicker to just buy new tubes the next time you're passing a bike shop and spend 15 minutes replacing them than spending several hours identifying and repairing the old tubes - and having the psychological weight of whether or not your repair was fully successful looming over you whenever you ride. <S> What could have happened ? <S> Not sure if anything in the valve is stuck. <S> How can I determine what is wrong ? <S> A number of things. <S> The tyre pressure could have been too high for the weight of the person riding it (you don't always need to inflate a tyre to the max pressure), the inner tube could have naturally weakened with age, the rider may have hit a pothole or thorns/nails without remembering it that pierced the tire and tube. <S> Ultimately; it doesn't matter. <S> The tube is punctured AND old; get a new one and brush it up as bad luck. <S> I doubt reverse engineering the problem at this stage will help you reduce punctures in the future. <A> Well, either the valves are not closing properly (may have dirt in them) or there are a punctures in the inner tubes themselves. <S> You can get the tubes out and test them for leaks by inflating them a bit and submerging them in water, then either patch punctures or remove valve cores and clean out the valves - or - if the tubes are quite old (older than 5 years) you should probably just replace them. <A> Tires pumped up to max pressure may blow up at the spokes due to a poor rim tape. <S> This does not happen immediately after or during the inflation process but it can take some time to develop. <S> In one of my cases, I heard a blowout and hissing of air at 2 a.m. though I'd pumped them at 10 p.m. <S> Alternatively, it could be just a regular tire/tube puncture that took some time to develop, and a high pressure helped it to manifest itself. <S> Which is good — now you can fix it at home, not on the road. <S> Open the tire, get the tube and inspect it. <S> If it is just a regular puncture, simply change the tube. <S> If you do not know how to change a tube in a tire, take your time and follow one of the numerous on-line guides.
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If it blew up at the rim, check the rim tape as well as it will blow up again with another tube if not fixed.
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Long post v-brake (or canti) shoes? (Canti studs not sufficiently inboard) Someone built me a small, custom recumbent bike recycled from older bike frames. He did a generally decent job, but seems to have messed up placing the rear canti studs. They should have been spaced inward toward the rim at least 5mm per side. At least, that's the estimate I get doing some measuring and initial setup. Where there's only about 4mm of pull left there (pads are contacting the rims at that point) there should be about 40-45mm between the noodle end and the right lever -- according to tektro's directions. I had first hoped to solve this problem by finding longer threaded post brake shoes. No one seems to market anything like that as a feature. The posts on these are 25mm, which look about the same as any others I've had in the past. I found nothing longer. Next, I tried to approach this with a pair of female-male m6 spacer on each side, but I can't get enough male threaded post to install correctly. My other potential option is (not my fave) canti brakes since he did put a canti stop bridge up top, just out of the photo. However, I'm not sure I won't have similar issues with the spacing, depending on post length. It appears that if I use a smooth post canti, like an altus , I might be able to get the far enough inward, since they secure by a loop pulling on them perpendicular to the direction of the post. (Probably should have gone for the canti brake first -- cheaper than the spacers were!) But not knowing the length of those posts (anyone?) I wasn't sure they'd solve the problem, and I wanted to avoid having to buy new brake levers as well, plus match the front brake to the back. (On this bike, the front doesn't carry much weight, so it should really have a weaker brake than the back to avoid locking up and washing out...) The final option that I brainstormed was to use some 5mm or 7mm thick by 20mm wide aluminum stock and build a short adapter that attaches to the inside of the brake arms (toward the rim, thus providing the inward spacing) and secures with an M6 screw to the brake arms where the shoe normally mounts. Offset about 8mm to the side (opposite, across the arm center point, for max rigidity) a 6mm hole to mount the brake shoe as normal, with the beveled spacers for making angular contact. Up/down would be accomplished with the normal slot. That would give me the spacing and the pieces are thick and short enough that they shouldn't flex much. It's a couple hours work with hand tools, I guess. Adding sketch. The stock I've got is good quality, pretty stiff, and mounting as shown in the sketch actually places the shoe post a similar distance from the middle of the lever arm as the stock mounting slot, and the flats of the middle of the arm are pushing the adapter toward the rim too. Second photo shows midline of the brake arm better than my sketch. Anyone ever run into a similar issue? Anyone know of longer threaded post shoes or happen to know what the post length is for smooth post canti shoes? Builder is willing to take it back, redo the rear end, which would mean re powder-coating as well, plus two trips shipping across the country. He won't charge for the fix of course, but it seems like a lot of effort and material, so I'd like to explore less resource-intensive options first. Failing longer studs, taking any and all ideas! <Q> There are a wider selection of wide rims available now, although I do not know if this extends to smaller wheel sizes. <S> Wider rims will likely mean running a larger volume tire, but there is plenty of room. <A> Fwiw the closest thing there is to a standard is 80mm post to post. <S> Comparing that number to what you're working with may be helpful. <S> Rim width does of course have an impact; 75mm is supposedly a better number if it's known that road rims will be all that's used. <S> The genre of brake that I think would work the best are traditional wide-profile, long-armed, smooth-post cantis ala Mafac and similar. <S> The reason I say that is the mechanical advantage characteristics of that type of brake get screwed up the least when the starting position of the arms is splayed in from the more intended starting point. <S> If you can make a low profile canti like an Altus work without running into that issue, then fine, but it's going to depend on what the post to post distance is. <S> They might buy you some millimeters <S> but I don't know that you'd be able to get them so extended as to solve this. <S> Edit: <S> Depending on what width rim you've got now, going with a wider rim could help the situation, although judging by the picture I doubt it would solve it all by itself. <S> Sun Rhynolites are cheap and make good rear recumbent wheels by their own right. <A> This is a collection of thoughts rather than a real answer, but pictures don't work in comments. <S> I'm sure I've used some in which the stud was a normal M6 bolt, which you could swap out by removing the rubber pad. <S> However the ones I currently run (Kool Stop) use a custom-headed bolt: <S> Maybe this will jog someone's memory, or maybe you can look around for ones that use a similar construction but the usual spherical washer arrangement for alignment. <S> Alternatively if you're prepared to use the spacers you bought already, you might be able to make them work on these pads, as you don't need nearly so much male thread for the alignment. <S> You may need extra nuts/spacers, and a lot of care and threadlocker -- I'd be cautious about extending the thread giving that you're relying on a single point fixing to stop you. <S> Canti pads have a much longer post. <S> Unfortunately at ⌀7 mm <S> I reckon <S> it's too thick to cut an M6 thread unless you can find them with alloy posts (I've got a few different ones <S> but they're all steel; online I find rumours of alloy posts). <S> Not all v-brake pads have the same length of stud. <S> Unfortunately I think you've already got fairly long ones. <S> I have some cheap but effective XLC pads with 25 mm unlike the ~22 mm of my other pads. <S> Finally, there exist v-brakes which take canti pads. <S> I have some on an MTBSO I use as a shopping bike but plan to keep outside work: <S> These are cheap and nasty, and came on a bike I date to early 2000s ( <S> which seems like the forks were badly built, if you're wondering why the brakes look wonky). <S> They might help, but on the other hand they might not, as the canti adjustment method needs a little more length than the typical V-brake method. <A> Thanks for tall the input, folks. <S> I made spacers and they do the job of moving the brakes in, but they introduce some funky angles and make the brakes come in heel first, and interfere with the tire sidewall, so that's not going to work out. <S> Unfortunately, the answer is going to be to send the frame back to the builder to have him redo the canti studs and re-powder coat the entire thing.
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Some v-brake pads have permanent shoes in which are fixed replaceable pads. A rear wheel with a wider rim could make up the gap, depending on what you have in there now. There are v-brakes, mostly early and/or cheap ones, that use smooth posts.
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Is there a trick to inflating a flat tire with deep section rims? I have a Schwinn floor air pump and its nozzle is the kind you push down and flip up the lever to connect. With a brand new inner tube installed I could not get it to connect with the valve as I have rims with a deep section, with these particular rims even inflated you only have the brass end of the valve showing. Is there an easy way to inflate the tire with this set up? <Q> Tubes come with various length stems to accommodate deep section rims. <S> There are screw-on valve stem extenders available for both Presta and Schrader that you could use to extend your stems. <S> (I think some Schrader ones are actually for car tires, but they would still work for a bike.) <S> With out an valve extension, to get started, try pressing down hard on the tire and tube where the valve stem is to press the it out of the rim so you can get the pump nozzle attached. <S> Having someone to help you will make this easier. <S> You can also thread a valve stem nut onto the stem to retain the stem when you try to get the nozzle on. <S> Another approach to getting started, before getting the second tire bead onto the rim, reach inside the tire, press the valve stem out of the rim, clip on the pump, then fit the second tire bead. <A> Well, it seems that your pump has both connectors: the car one and the Presta one. <S> (Sorry, I'm not sure about the terminology in English, in Czech they are "auto" and "velo".) <S> The trick is to get this little gadget which is screwed on top of the valve <S> and then the pump is connected. <S> Now, as the gadget is wider than the valve, it prevents the valve from slipping into the rim. <S> I found it on Amazon under the name Bike Adapter for Air Compressor . <S> However, here even some bike shops sell them. <S> Just be sure you get the correct thing! <A> One trick I've used for wily valve stems is to use my thumb or a broomstick on the floor or some such object to push the stem as far out of the hole as it will go. <A> The valve stem may simply not be long enough. <S> Try, as previously suggested above, press on the tread directly opposite the valve in order to push the valve farther through the rim. <S> Hold it in place while connecting the pump. <S> The better solution, again, as mentioned above, is to replace the tube with one having a longer valve stem. <S> If you do this, you may want to consider switching to a tube with a presta valve (you would also need a small adapter for the rim hole, available at bike shop, because the presta valve is smaller in diameter). <S> Presta valves have a nut that tightens against the rim to prevent the valve stem from retreating into the rim.
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The real answer is you need inner tubes with longer valve stems.
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Uneven friction in front hub after rebuild I serviced my old mountain bike after 6 years of use. This included replacing balls and regreasing the hubs of the bike. When I tightened the lock nut on the front axle and checked for wobbling the axle felt like it was okay (no wobble). And when checked if the wheel turned freely, the wheel turned smoothly for almost a full turn but I'm getting enormous friction at one specific angle. I've loosened the nuts to check if the hub was overtightened. Then friction disappears but wobbling comes in instead. My front hub is a Shimano HB-RM60. I've replaced my bearings with 3/16" ones. I've disassembled and reassembled all parts twice, but couldn't find what causes the friction at that particular angle. Now I am not sure whether I cross threaded something or something is in bad condition (like a cup or cone). Is there any advice I could take to check it? Update: Apparently my axle is bent. I think this is my problem. Update 2: I've replaced my axle with the new one, lubed and packed up everything. Now the wheel turns smooth constantly. An addition to answer is, after checking cup and cones, check the axle too. <Q> Disassemble the hub, clean away the grease, and carefully inspect the surfaces of the cups and cones. <S> If you see irregularities then that's probably "spalling" and it means that the part must be replaced. <A> Did you mix old ball bearings with new ones? <S> Or mix balls from the left side to the rear? <S> This is why best practice is to just replace all of the bearings from new ones that come from the same batch/box. <S> They’re so cheap <S> it’s not good to recycle them anyway. <A> In general, a recently regreased hub tends to show more friction than it had before the regreasing. <S> In normal circumstances, I would recommend giving it a spin during a ten-twenty kilometers ride and then would recheck if the friction is still bad. <S> However… It is not clear how "enormous" the friction at that position is. <S> If all the balls are new and the races did not look to be beaten to death or at least looked evenly worn, the only explanation I can imagine is that you've put more balls to one or both sides of the hub than necessary. <S> Did you count amount of old balls per side? <S> It is safer to set one ball less than optimal than to cram in one ball more. <A> this wouldn't account for enormous friction, but one way to check for non visible palling on your bearing surfaces is with a ballpoint pen, just draw around the race and you'll be able to feel any cracks or divots. <S> (if you hadn't said you'd replaced the bearings i'd say it was a broken ball)
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Uneven wear in the ball bearings can cause this.
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Keeping cables free of dirt when in transporting Any ideas on how I can keep grit and all of the other nasty road stuff when transporting my bicycle 2,000 plus miles this spring to get home? It will more than likely be rain and snow on the way. They will be on a bicycle rack behind our Chevrolet Equinox. The suggestion of garbage bags over the cables sounds promising. Update: Thank you all for your ideas. It looks like I will be driving into wintery conditions the closer I get to home. I wish I could afford an enclosed trailer, but I have no use for it after transporting bicycles. Bicycle covers are great, but they block the vehicles turn signals. I was looking for a low cost solution. I am going to remove all of the cables and wrap parts of the bicycle in shrink wrap. Thanks again for all of the ideas. <Q> I'm assuming that you're putting the bike on a bike rack on a car or something. <S> Note that different racks and cars can give different amounts of dirt accumulation; for example, the roof of a Chevy Suburban would probably be cleaner than on the back of a Mazda Miata. <S> One solution is to just let it get dirty and then clean it off when you get to your destination. <S> Yet another solution is to put the bike in the car or trailer or something. <S> I can get a 58 cm road bike in my hatchback <S> pretty easily provided <S> I don't need to have someone in the back seat. <A> Wrap the bikes in plastic stretch wrap used for protecting furniture when moving house. <S> It wraps tightly so will not whip around and should be much easier to shape around a bike than a polyethylene tarpaulin. <S> Secure with judicious amounts of packing tape. <S> You can poke holes in it for the rack arms to go through (or put the bikes on the rack then wrap them). <S> You want to protect against crud coming up off of the road surface so a few holes at the top will not matter. <S> Perhaps put a couple of square feet of cardboard inside the wrap to soak up any moisture that manages to get inside. <A> When transporting a bike on a bicycle rack behind a car, there's all manner of bicycle-destroying grit, grime and chemicals that can get to your bike's components. <S> Whether it's snow and salt or mud and oil, it can all cause damage to the workings of your bicycle. <S> This means, then, that protecting your bike is the number one priority. <S> The best method to protect the bike is using a simple cover over the bike. <S> This will stop rain, snow and any dirt from getting to the bike. <S> This is probably the most common way! <S> However, there are some drawbacks; Water, when it evaporates, can condensate within the cover if it's waterproof. <S> They also don't help paintwork when in windy situations. <S> I had a gorgeous red road bike which it's paintwork was brutally damaged by the cover after a 300 mile drive, and the bike had never looked the same again. <A> You can try using a bike box/bike case. <S> Those are cases specifically designed to pack your bike to be easily transported and protected from damages and dirt. <S> See the video below for the way you can use it.
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Another is to wrap the bicycle parts in something like trash bags taped tightly to the bike, leaving the parts necessary to grip onto the rack exposed.
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Compatibility of bar end shifters and 10 spd Tiagra I want to try an aero bar type set up, with bar end shifters on my 10 speed Tiagra road bike, do I need a particular bar end shifter to do this? <Q> With Tiagra in particular this answer is different from if your bike had any other 10-speed group. <S> Presently there are two different 10-speed Tiagra generations, 4600 and 4700. <S> (So the STI from one is ST-4600 and the other is ST-4700, etc). <S> 4600 uses the same classic actuation ratio that all pre-11-speed Shimano road groups used other than first generation Dura-Ace. <S> 4700, however, is an oddball group. <S> It's 10-speed but uses the new 11-speed actuation ratio, resulting in a situation where ST-4700 is currently unique in Shimano's history in terms of number of clicks (10) and amount of cable pulled per click. <S> No other shifters interchange with ST-4700, including any of the bar-end models. <S> , there's no way of doing this. <S> You would have to also get a new rear derailleur from any other 10-speed road group, like for example RD-5600, RD-5700, RD-6600, RD-6700, RD-7800, or RD-7900. <S> Then it will work. <S> (The front derailer will be friction so no issues there - otherwise it would also have a cable pull issue.) <S> It hasn't become clear yet whether more 10-speed groups with 4700's cable pull will be released, but I wouldn't wait for a bar-end version. <A> Yes. <S> This sounds obvious but you need shifters compatible with the cable pull ratio of Shimano road derailleurs. <S> SRAM uses a different cable pull ratio. <S> I think bar end shifters appear in the 105 and above ranges. <S> Component manufacturers such as Tektro and Microshift also make Shimano compatible shifters. <S> Update - The above is true for Shimano 10 speed and below except Tiagra 4700 generation. <S> See @Nathan Knutson's answer. <A> If you have a Tiagra 4700 or a GRX 10s deraileur, there are two models available from Microshift that will work. <S> Microshift main page BS-A10B: <S> right side index <S> only BS-T10B: <S> right side index and friction switchable <S> Both have left side friction shifter.
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Any 10 speed shifter made by Shimano will of course work. Each shifter model will specify which group set it is compatible with. So if you have 4700-level Tiagra the answer is no
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I get dizzy when I dismount. Causes? Saturday I went on a ride with the local cycling club. At a certain point in the ride (after about 20 miles/32 km), I was extremely tired to the point that I decided to get off of the bike and walk for a space. After dismounting I became so dizzy that I fell over (and don't remember falling over). Oddly enough, I rode the same route the week before without any problems. I am curious to know if anyone else has had this problem and what steps they took to effectively deal with it. The two possible causes that I am already aware of are: I am taking blood pressure medications (amlodipine and lisinopril) I am not entirely sure my bike is a good fit; after about twenty miles I find it very difficult to find a comfortable position while riding. I was dead-dog tired at this point in the ride (I had just gone up a fairly steep hill in a stiff headwind), and that probably exacerbated whatever is going on here. Clarification: I have spoken to my physician about this, about nine months ago when this first happened to me. His advice was that this was probably due to the readjustment of blood pressure after changing positions. This makes sense, as it only happens once I dismount. My meds are for high blood pressure, so they could be doing the job too well. I actually drank more on the ride where I was dizzy than on the ride where I was not, but the doctor has advised that I drink more, so I need to scrape together some funds for portably fluids. Update Went out riding with the local cycling club. I had a bit more to eat before leaving the house, and I brought along a whole lot more water, and a banana which I ate when the group stopped. I was fine until the 26-mile point, when I got a flat tire. None of the problems of the prior week appeared. Final Update I did the Houston MS 150 in April. I downed a banana or and equivalent amount of food at each stop, and drank my fill of water as well, and drank every time my mouth felt dry on the road. No dizziness at all. <Q> It sounds like you over-exerted yourself and " bonked " – your body ran out of sugar so you fainted. <S> It may also be blood-pressure related: people with low blood pressure are (as I understand it) more susceptible to fainting. <S> Since you're on blood pressure medication, <S> you should talk to your doctor . <S> I don't think bike fit is really a contributor <S> but, of course, improving that would make you a happier, more comfortable cyclist so you should do something about it even if it doesn't help the problem you most want to fix. <S> * <S> In this context, snacks are not evil and you should eat them. <S> Or, if your username indicates that you are the snack, consider eating yourself. <S> However, this probably isn't a long-term strategy. <A> A further effect is likely to be that exerting yourself hard on an uncomfortable bike means you get to the top, get off, and have a good tall stretch. <S> That could make anyone a little light-headed and dizzy. <S> Combined with the points suggested in David's answer this was probably enough to tip you over the edge. <S> Just getting off a bit more gently, and slowing down the urge to stretch (take the first bite of a snack first) could be enough. <S> Don't underestimate the fatiguing effect of a strong headwind -- the same route isn't the same ride, and you don't get back the effort when you turn away from the wind. <S> And as others have said, talk to the doctor <A> I would recommend drinking more water. <S> I frequently experience symptoms of dizziness, tunnel vision, heart-racing, cold-sweating, from simply standing up too quickly. <S> My legs are quite large compared to my upper body and I have naturally very low blood pressure: as a consequence, when I stand up blood rushes from my head to my legs. <S> The best solution for me is to stay very well hydrated at all times. <S> Drink more water --- even if it doesn't work it's still a good idea! <A> How's your breathing and circulation? <S> If you're feeling uncomfortable and adjusting your posture to compensate, you might be putting pressure on an artery in your leg or somewhere else, combined with your blood pressure medication maybe your circulation is being affected. <S> When you get off the bike and suddenly become upright, and are no longer putting pressure on your ass/legs, this combination might suddenly increase your circulation to your legs and your brain may have access to a little less oxygen for a few moments until your circulation/heart/breathing catches up. <S> As with other comments, make sure you have enough fluids & sugar, but breathing and circulation are important and they can be affected by your posture/position, so add some padding to your seat or try some thicker pants or whatever you have to do to be comfortable on the bike. <S> Also consider your seat and handlebar height etc.
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On a bike, you'll be dehydrating yourself considerably; combine that with your blood pressure medicine and I'll bet you're experiencing a very similar problem. In that case, you reduce the risk by eating more while you ride* and by listening to your body more and backing off when it's getting too much.
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Is it better to get a commuter bike with a front suspension or without one? Is a commuter/city bike without front suspension comfortable? <Q> Commuter or city bikes are designed for paved surfaces. <S> Suspension forks add weight, which brings a different type of discomfort as you have to exert effort to move that weight around. <S> This gets worse the more inexpensive the bicycle is. <S> Low end suspension forks are heavy and have poor performance. <A> I find the ideal commuter bike is: lightweight, reliable, and inexpensive. <S> Reliable: <S> Light weight: it has to be lightweight as you’re navigating it around bike stands, carrying it up stairs, taking it over curbs, and putting it on bus racks or in the trunk of a car that’s come to pick you up when and if your bike breaks by the side of the road and you can’t fix it before being late for work. <S> Inexpensive: <S> your commuter bike often has a shortened lifespan. <S> It either gets stolen, hit by a car, or damaged by the elements. <S> If you’re buying new, the bike you’re looking is likely inexpensive but likely fails in terms of reliability and weight if it has front suspension. <S> Most bikes that are inexpensive and have front or full suspension are what we call on this forum somewhat derisively [Bicycle Shaped Objects] or BSOs. <S> A used steel-frame road bike or hybrid with no suspension that can fit panniers is often a much better choice for commuting. <A> The drawback of the suspension is that it can swallow energy, i.e. if you stand up to push the pedals harder, you can not exert the same force, plus I find the motion of the suspension annoying in this situation. <S> I used a bike without suspensions for more than 20 years, and I was happy with it both on paved and dirt roads. <S> In my opinion a good seat and well adjusted handlebar adds much more comfort, than a suspension. <A> I think a big impact of with/without suspension is maintenance . <S> Suspension brings more movable parts, which means more maintenance and repair costs. <S> Suspension can feel comfortable when it works, because it absorbs some shocks. <S> But one other thing it does, is to absorb energy you might want to use for speed, not bouncing. <S> Imagine standing on your bike and pedaling really hard; you want that energy to drive you forward, but with suspension some of that energy goes into bouncing you up and down. <S> Sometimes you need suspension, like if you're going offroad or riding on roads with lots of holes. <S> But in a city you might prefer not to have suspension, as you'll get lower maintenance and more energy efficiency. <S> For a commuter bike, I'd recommend something dead simple. <S> Fewer bells and whistles that will eventually break. <A> It depends. <S> If you are going to ride with your commuter bike on roads where a front suspension benefits your riding or comfort, it is better to have a front suspension. <S> If, however, you are going to ride on roads where a suspension fork does not bring you any benefits, it is better to have a rigid fork. <S> There is a caveat though: <S> If you like or dislike front suspensions for other reasons, e.g. you like or dislike the looks of it, you have to evaluate above decision considering these other reasons. <A> Basically depends on commute, trade off of comfort over efficiency. <S> My commute is full of speed bumps. <S> I prefer the ability to ride at speed over those bumps without having to keep doing 'brace-brace-brace' to avoid jarring to bits. <S> Maybe its because I'm on old side. <A> I would add that while I agree with the above answers, the conditions of the road on your preferred route might have a big impact on this decision. <S> I opted for a fixed fork for both ease and cost, but now regret it as the roads I ride on are extremely pitted and bumpy near the edges (approximately 1-2 cm irregular ridges / patches where the top surface has broken away). <S> I've yet to try padded gloves or raising my handlebars to take some of the vibration out, I mention it as I assumed that main roads that feel perfectly smooth where my car tyres are positioned are not necessarily so nearer the edges where you'll be riding. <A> If you can afford it, for the average fun-loving , sociable person, suspension is a must! <S> Fixed forks will limit you options for comfort in these situations and in fact the shaking handlebars can be seriously annoying along with any unstable traction. <S> Bikes don't have to be taken too seriously and should be a staple part of the fun of a normal life.
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A suspension fork on such a bike is not going to add much comfort, except perhaps when riding over potholes or kerbs, which are avoidable. A commuter bike can’t fail or you’ll be late for work. There will be times when instead of doing the commute, you may want to do a social ride with friends along riverbanks and other areas where the path will be less than smooth.
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I have got 29er tires and I want to upgrade to 29 plus Hi I am just about to take delivery on a new bike (Carrera Hellcat) with 29 inch wheels however I want to upgrade to 29 plus wheels and I have found some tires that will work but will my normal inner tube and wheel work with the 29 plus tires? Thanks in advance. <Q> Factors that decide whether or not a certain tire width fill be compatible with your bicycle are many. <S> This applies to any transition that keeps the tire diameter (29 → 29+, 27.5 → 27.5 <S> +, 26 → 26+). <S> The most important, in my opinion, are the following. <S> Both in increased width and height . <S> Typically, bicycle vendors designate if a bike is "plus" compatible. <S> If not, the risk is high that no tires designated as 29+ will fit in a 29 frame. <S> In such case, you'd better consider switching to 27.5+ wheels if you are firm to go plus. <S> Your rim width. <S> There are limits to how wide/narrow a rim can be to accept a given tire width. <S> Here's ERTRO guidelines, copied from here : <S> Having a too wide or too narrow rim would result in a suboptimal performance or even straight unstable wheel. <S> Another picture from 1 : Actual tire dimensions when installed on a given rim may differ from what's designated on it. <S> There are a lot of reports online that a 2.6" tire actually measures closer to 2.7" or even 2.8". <S> The same applies to non-plus tires: <S> a 2.1" can sometimes be 2.25" when installed on a wider rim. <S> Knobs can add to width and create problems with clearance. <S> I recommend either playing it safe and taking a narrower "plus" or finding an online review with actual measurements of chosen tire applicable to your situation. <S> Other factors are less deciding. <S> Inner tubes should be fine. <S> There might be some extra muscle effort needed if you install tubeless-ready tires on a regular rim (or was it the other way around? <S> cannot remember). <S> If your fork does not accept wider tires, you can change the fork. <S> If it is the frame that has too narrow rear wheel clearance, changing it equals practically to obtaining a new bike. <S> Getting new wider wheels is easier, because you'll then have two pairs of nice wheels. <A> According to the Halfords page the Carrera comes with 2.2" front and 2.0" rear. <S> Going up to a 3.0" tire is probably a stretch. <S> The limiting factor is most likely the clearance between the chainstays. <S> If you can, go into a branch of Halfords and have a look at an example of the bike and see how much clearance the tire has there. <S> Also check the fork and seat stay clearance while you are there. <S> The rims may also be below the optimum width to support that wide a tire. <S> If the Carrera won't take 3" tires, as you are buying new , don't event think about changing anything to support wider tires (such as switching to 27.5 wheels), just find and buy a bike that comes with the tire size you want. <A> Most "plus bike" frames have a lot more tire clearance around the rear wheel, especially near the front chainrings and front derailleur. <S> You will see many of them running a single chainring up front for this reason. <S> In your case, the tires in the original post hyperlink will not fit the hellcat 18 mountain bike. <S> Reason: <S> There isn't enough room inside the frame [as it wasn't designed to fit plus-sized tires].
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Your frame and fork clearances should allow wider tires. Some people use 27.5+ wheels on 29-ers, but if bike geometry is not an empty sound for you, you might consider doing some calculations before going that way.
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How can I make better use of the dead space under my bottle cages? There's an annoying/useful bit of space under each of the bottle holders on all of my bikes; I currently strap a spare tube there (which keeps the right tube on the right bike). The tube is in a bag but the bag tends to snag and rip, and dirt/grit gets in. It also doesn't look very nice. I should be able to make much better use of this space, to hold more than just a tube, and hold it better I don't believe there's a product on the market, so I think I'd like to repurpose/make something. It should be secure against falling off, and keep the dirt and the worst of the water out. I've found this winter that on long rides (200km+, essentially unsupported but with occasional food stops) the bike is fully loaded. I don't really want to fit the rack/panniers (weight and drag) when I'm already pushing myself quite hard, and can't add a handlebar bag because of my lights. I've already got a top-tube bag (snacks/gels, backup battery for phone/lights), saddlebag (first aid kit, foil blanket, more snacks/gels, spare tube, jacket and shoe covers strapped underneath if not on me), 2 water bottles, tool case in 3rd bottle cage, jersey pockets full (2nd breakfast/litter, money/cards, any extra warm layers) <Q> Good question - I've wondered the same. <S> I looked at the Specialized SWAT toolbox for inspiration, but it only fit certain models of frame. <S> https://www.specialized.com/us/en/equipment/bike-accessories/swat-technology/c/swatstorage <S> Here's another specialized product to do exactly that: https://www.specialized.com/us/en/emt-cage-mount-mtb-tool-for-right-zee-cage/p/132369 <S> Downsides of this is that it only fits their multitool and nothing else. <S> Also exposes the tool to a lot of dirt and muck that it wouldn't see if higher up. <S> I have tried a solution of using a frame mount bag right at the front of the main triangle. <S> Advantages are that its forward weight so helps me keep the front wheel down on a steel climb, and I can put a USB battery in here for powering my gopro on long rides. <S> Alright this bag was measured for another bike so its a bit saggy here. <S> The pump hook gets in the way, and the downtube is much smaller and a different angle from the designed bike. <S> Flaws - the zip is the wrong way around, and should close forward <S> so cables can come out easier. <S> Velcro is all wrong for this bike. <S> I also use a top-tube bag for more storage when on a long ride. <S> That holds snacks and my phone running on another USB battery (because its annoying when strava stops recording.) <A> I recently saw an instructional video that you might be interested in: While there are some off-the-shelf products that are similar (the one I use is the Z-box by Zefal, in the large/adjustable size), this video's DIY hack has the advantages of being cheap (or free if you have an extra bottle laying around that fits the bill) AND the end result is kinda stealthy, in that it doesn't look like anything worth stealing. <A> Take a block of styrofoam, whittle/ carve it into the perfect shape to fit that area for your specific bike/bottle combo, then use that as a mold to wrap 1-2 layers of fiberglass around (using a fiber glass repair kit from automotive store), then cut the end or top off that, and you have a container for the space. <S> Figure out how to waterproof the seem around the cut, add velcro straps to your seat and down tube. <S> For the repair kits, you can buy them from automotive stores or Amazon and a small repair kit probably includes enough fiber to do a small project like this. <S> The kits I have in mind are in the $20-40 USD range. <S> Example: Resin <S> Cloth <S> If you wanted it to be a little more slick and/or lightweight, there are also DIY carbon fiber kits and carbon fiber mold kits. <S> You're looking about 3-4x the cost of the fiberglass kits. <A> You might also be interested in the B-RAD system by Wolf Tooth. <S> http://www.bikepacking.com/gear/wolf-tooth-b-rad/ <S> It looks pretty adaptable and enables you to reposition the bottle(s) to allow for an accessory strap mount. <S> For example, like this: <S> NOTE: <S> The frame they chose to model the product doesn't look like the best use case. <S> Removing/inserting that aft bottle deson't look easy. <S> Regardless, they have more photos at the link above. <A> Another option (for completeness) is to move the dead space up by moving the bottle cage down. <S> I hinted at this in a comment, but I've tried it recently: <S> I had to swap to a cheap plastic bottle cage on the seat tube, with the top screw hole using the lower boss on the frame, and a heavy-duty cable tie at the bottom of the cage (unfortunately hidden by the crank in the photo). <S> That then makes room for a small frame bag above (even with a 1 l bottle like the Magnum in the downtube cage). <S> It's a bit of a stretch to get at the lowered bottle, but at least in my case it can be accessed when freewheeling. <S> The spare tube, tyre levers, chain link and brake pads that I used to carry under the bottle cage are now in a pouch between the seatstays and rear mudguard (visible at the top of the pump in the photo). <S> The black cylinder with the yellow tape under the downtube is my full toolkit; the pouch containing tube etc. <S> is a set of cheap consumable parts so the right parts are with each bike.
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You could try a DIY custom fiberglass tool compartment for that area. Another option is to mount things directly to the waterbottle cage mounts.
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Can I make this bike fit me? There are two questions here really though they both have to do with fit. Today I tried a Baad Raad electric fat bike.This question isn't about batteries or fatties.I just wanted you to know this bike will be used on rough trails,snow and whatnot. The question is about fit.This is a one size fits all bike.The frame is said to be a large one.It seems to be about ninteen inches.I am six foot two. I tried the bike out andwas pleasantly surprised as far as performance is concerned.When in pedal assist it does exactly what I want it to do and more. Do some bikes have shorter cranks on them?I could still put up the seat more no problem.The cranks feel short to me. Is that because the seat should be raised?Is there more to it than that? What about the handle bars?My mechanic says they can be raised as well.Will that affect how the bike fits as far as legs are concerned? The price is more than right if I can tweak the fit a bit. <Q> Years ago, the US Airforce commissioned the design of a 'perfect cockpit' for a new fighter, spending millions measuring and testing pilots and coming up with the right cockpit for the perfectly average pilot. <S> Only to find there was no perfectly average pilots to fly plane. <S> After that, they made planes with cockpits adjustable to the actual pilots that was flying the plane. <S> Its cheaper and gives better bikes to make different frames. <S> All that aid, the bike might fit you - <S> The US Airforce never found their perfectly average pilot, maybe the manufacturer of that E-bike has found there perfectly average rider in you. <A> Do some bikes have shorter cranks on them? <S> Yes, but not really. <S> The standard crank lengths are 170, 172.5 and 175mm. <S> Those are so close together (2.5mm is a tenth of an inch) <S> that I'm pretty sure it would be about the last thing you noticed, if you jumped onto a new bike and it had different cranks to what you were used to. <S> but, basically, any bike you buy will have one of the three standard lengths. <A> A big part of what makes the cranks seem "short" is that the bottom bracket height is very high. <S> On one hand, you might argue it helps improve clearance <S> but really it's a function of the design with relatively large wheels. <S> Because the bottom bracket is so high up, your legs can't stretch as far down as they might <S> and so you have to raise the seat height, which then brings in a whole cluster of other problems. <S> Sheldon Brown actually wrote about this problem here: <S> https://www.sheldonbrown.com/upgrade.html Bottom-Bracket Height Traditional bikes for road use normally had bottom brackets about 10 5/8" from the road. <S> Everybody knew that they shouldn't pedal while leaning sharply into a high-speed corner. <S> When mountain bikes became the default style of bike for most buyers, people got used to 11 1/2", 12 1/2" or even higher bottom brackets. <S> This is a good thing for serious off-road riding, giving better clearance for logs, rocks, ruts and other obstacles. <S> Once the marketplace had become accustomed to high bottom brackets, manufacturers became afraid to sell bikes with low ones any more. <S> The nightmare was that some clueless rider with a good lawyer would pedal through a high-speed corner, catch a pedal, spin out and crash. <S> In court, the shyster could point to all the other bikes on the market with high bottom brackets, and accuse the manufacturer of making an abnormal, unsafe bike. <S> A higher bottom bracket should require a higher saddle. <S> The higher saddle precludes putting a toe down when stopping for a red light, stop sign, etc. <S> This is a cumulatively major inconvenience for cyclists who ride in built-up areas. <S> It generally makes starting and stopping noticeably more awkward. <S> (See: Starting and Stopping.) <S> Many cyclists, unaware of this change in geometry, adjust their saddle height as they always did, with respect to their reach to the ground. <S> This results in their saddles' being too low for efficient pedaling, which is harmful to the knees and encourages excessive standing pedaling. <A> Your main concern will be the saddle. <S> From the image, it is a) very low by default, and b) the tube in the frame that holds the seat post ends very low. <S> Your body dictates the distance between pedals and saddle. <S> With the frame you've shown, that means that you must use a ridiculously long seat post. <S> And that is a problem: <S> The longer the seat post, the longer the lever that exerts bending force at the point where the frame starts, and thus the greater the danger of breaking the seat post. <S> This is a strong security concern in my eyes as I have indeed already managed to break a seat post. <S> I would not try to fit this bike for a 6-foot person.
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For a good fit, your saddle must be high enough so that your leg is almost fully stretched when going through the lowest point of the pedals. Bikes take this further - the frame is not adjustable without making it heavy and unreliable, and unlike an aircraft, frames are relatively cheap compared to the the rest of the kit. A high bottom bracket has no real virtue for most on-road use, and actually represents a fairly serious drawback for the typical rider. From what I can see, SRAM make cranks between 165 and 177.5mm; Shimano and Campagnolo make at least 165–175mm
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Keeping the bottom of your legs warm in very-cold-weather biking I come from a country with a warmer climate,but am now living in the Netherlands. It's not that bad really, but in winter, it sometimes gets to -5°c / -6°c - and occasionally with strong head wind when I cycle to work. I'm also very sensitive to the cold, and can catch a cold very easily, so I need to cover up. I'm wearing street clothes, rather than cycling-specific gear. Now, I'm doing that well enough - for the most part: Gloves, balaclava, winter coat with a head piece, wind-and-rain overpants (is that a word?), gloves and well-insulated shoes. So, I mostly stay nice and warm. There's one problematic spot though: Where my shoe ends and my pant-like clothing begins: None of it is long enough to "grip" the shoe, nor do I think I want it to be. It's a shoe, not a boot (and I dislike boots); so not long enough to tuck the pants inside the boot/shoe. If I wore two pairs of socks, one on top of the other, I would have a hard time fitting my foot into my shoe. What do you do, or what would you suggest, to keep that tricky area warmer? <Q> Or wear mid-calf or knee length socks and roll the upper part down for double or triple coverage on the ankles. <S> Or, mini ankle warmers :-). <S> Pics of my Pearl Izumi MTB overboots. <S> The sole is exposed so walking is possible. <S> (Not a product recommendation, just what I happen to own.) <A> I would think that leg warmers will suffice for your situation. <S> They come in different sizes(width) and generally cover from the top of the shoe up to the middle of the calf. <S> I wear them a lot in cold weather since I suffer from cold feet and hands due to thyroid disease since I was a teen and ended up having both types of the disease when I was a teen. <S> It took me years to find them since there was no internet then; you should have no problem accessing a supplier now. <S> The really neat thing about them is that you can wear more than one pair at a time <S> and yes, they do make them for men. <A> Wear skiing socks <S> They are long enough to cover the legs below the kneelings <S> They are very warm <S> They fit into most shoes if they are not overly tight <S> They often offer some protection <S> There are some in bright colors, what makes them great for visibility <S> They or similarly long and thick socks are very popular amongst bicycle messengers <A> If you wanted to go cheap, you could just take a pair of socks and cut off the foot or even half the foot, if fit into the shoe is the problem. <S> Then wear this over your ankle and part-way down into the shoe. <S> I like the idea of improvisational engineering so this works for me. <S> I do something similar for my wrists, although in that case it goes all the way to my fingers. <S> Toasty warm. <S> I have a pair of gaiters from backpacking <S> but I hadn't thought of that <S> , I'll try that next time. <S> I bet that'll be great. <S> Those shoe covers and overboots look great too. <S> I went though some plantar fasciitis. <S> To fix this (along with stretching) I got custom orthotics which mandated bigger shoes, and I got them big enough to wear two pair of socks all the time. <S> That alone is enough to keep my ankles warm on all but the coldest days. <A> Wear "kniekousen", i.e. socks that go up to your knee. <A> What you might be looking for are Snow Ski Leg Covers or Gaiters . <S> It's a waterproof and windproof thing that covers your legs from under the heel up to mid-thigh. <S> The good ones also have a little hook in front that's attached to the lacing of your shoes. <S> This really works wonders for ankle thermal comfort. <S> I'm not sure how easy it is to get ski equipment in the Netherlands in general though.
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I would suggest shoe covers, which look like a boot and cover the ankle.
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What is the proper way to cut brake cable housing? Unlike this question , mine is about cutting the housing. All I've used with random success has been a pair of pliers with a good sharp inner cutting tool. Is there a better way, or a proper tool for the job? I am trying to avoid pulling the inner wire cable and fraying them. Thanks <Q> There is a proper tool that is probably the best solution. <S> They cut so that it does not smash the ends or the metal inside of the housing. <S> Many also have an awl in order to help reform the end if any smashing or deformation does occur. <S> Most look something like this: It is also possible with a brand new razor blade but the proper plier like tool makes it a lot more quick and easy. <S> For hydraulic hoses they differ slightly because of the difference in hose material, there are two type of hydraulic hose cutters, one that looks a bit like a pill cutter such as this: Or the handheld variety that function quite similar that looks like this: <A> Cable housing are supposed to be cut with a proper cable and housing cutter tool, such as the Park Tool Company CN-10 . <S> These tools have a shearing action and curved blades that help prevent the housing being crushed. <S> Pliers have blades that meet rather than shearing past each other thus must crush the housing before they cut it. <S> I'm pretty sure that any similarly shaped cutter would work though. <S> This tends to melt the inner lining though, requiring some clean up with a small drill bit. <A> While the Park Tool is the ideal tool, it is sort of a one trick pony. <S> Meaning using it for anything other than cable housing and inners will likely damage it. <S> I use a Dremel (brand name for an electric die grinder). <S> With an abrasive cut-off wheel it makes quick, clean cuts. <S> The multiple accessories make it more versatile for about the same cost.
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I've cut cable housing with a Dremel and an abrasive cut-off wheel.
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Help selecting between wire/folding tires I’m hoping someone can help me decide whether to go with the wire bead type or foldable Kevlar. What are the advantages/disadvantages of each? The bike is an old Fuji that originally came with 700x19c tires. I’m not an avid biker just riding around on bike paths mostly on weekends. Maybe ride about 20 miles a weekend, but since I’m in the market for new tires I’m looking to purchase wisely. Thanks <Q> For most of us it makes little difference. <S> Kevlar beads are supposed to be harder to fit but the hardest job I've had fitting tyres has been with wire. <S> Some tyres are available in both (there's normally a little difference in the compound as well). <S> The kevlar version is nominally more expensive, but can be cheaper if it's stocked in more competitive places. <S> I found this with my winter tyres. <S> As the kevlar version folds it can be cheaper to ship as well. <S> The weight saving of kevlar is real but small enough that you're not going to notice unless you're racing at a high level. <A> Advantages (Kevlar Bead) <S> Lighter construction weight <S> Packs down <S> smaller <S> so a spare tire can be easily transported Great for touring off the beaten track where tire damage is possible. <S> Usually found on higher end tires (i.e., higher performance). <S> Manufacturers typically use Kevlar beads on higher quality tires, which should include higher quality casing and rubber. <S> The result is usually a tire that is that are more supple (i.e., comfortable) and less rolling resistance and higher traction (this is of course not universally true and has little to do with the material used in the tire bead) <S> On average wire beed tires tend to be found on the lower end tire models which often use cheaper rubber, casing materials. <S> Disadvantages (Kevlar Bead) <S> Cost (wire bead tires always cost less). <S> For applications where high performance is not required (e.g., commuting, casual riding), why spend extra? <S> Some claim kevlar bead are harder to fit, but I have never found this to be the case. <A> Very easy. <S> Wire beads are heavier and used on less expensive tires. <S> If you are not looking for performance or weight saving, you can safely choose wire bead. <A> With the exception of treks across Australia or some such (where folding a stowed tire is useful), "folding" tires are mainly a convenience for the supplier. <S> They are a major inconvenience for the user, since when the tire is unpacked it's badly distorted, and it takes considerable effort to force it into shape. <S> It's not just that the tire wavers in and out along the fold points, but also, since it was shipped flat, the diameter of the tread is almost equal the diameter of the bead, so it won't readily take a "tire shape" with a roughly circular cross-section. <S> There probably are "normal" tires with Kevlar beads, but they're in the minority.
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Kevlar beads are lighter and are used in higher end more expensive tires.
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Can I use fiberglass cloth and resin to fix tiny holes in fenders? I'm trying to restore an adult tricycle and the fenders have multiple very small rust holes in them. Can I cut fiberglass cloth and make a "sandwich" with them with the fender in the middle and then cover both sides with resin? Or would a substance like "Bondo" be better? <Q> Since it is no load carrying part and if you keep enough clearance between the repaired spot and the tyre there should be no problem. <A> Both will be workable solutions, provided they are applied correctly, and sealed/painted after. <S> Do remember that rust is pervasive and never-ending. <S> So you have to de-rust what metal is left properly and not just bog over it. <S> Also consider that the underside needs to be smooth like the top/visible side too - otherwise water and muck will collect on any protrusion. <S> If you're not fussed about originality then consider replacing the mudguards/fenders with modern-day plastic ones. <S> They will never rust and will provide a weight saving too. <A> Fiberglass is a good one. <S> If the holes are very small you may not need to fix them at all unless the appearance bothers you. <S> Any water drop hitting the fender will not have much go through, so the fender will do its job the way it is.
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Take care to sand away any rust beforehand and treat the rusted part with rust removing chemicals. If the holes are small there is no stress here so any way of filling them is fine. You want to clean the fender to make sure the resin will adhere. Bondo would be fine as well.
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I rode a children's bike, now the chain is sagging - is it ok to shorten it? I know that I shouldn't have, but I had a go on my son's bike ( https://www.giant-bicycles.com/au/xtc-street-20-2012 ). I think that I stretched the chain. It's sagging now with about 3" of vertical play at the point between the cogs. So - can I buy a chain breaker and just shorten the chain, or should I get a new one? <Q> If this happened over the course of 1 ride, it sounds like the wheel just slipped forward in the dropouts. <S> If you loosen both nuts on the rear wheel axle and pull it backwards evenly, you should be able to retension the chain to proper working specs. <S> Then just tighten it back to a torque of pretty f**ckin tight so it doesn’t slip again! <A> I think that I stretched the chain. <S> No, you most likely did not. <S> Plus, if a chain is really overloaded, the links will separate (i.e. the chain will tear) before the force is great enough to actually stretch the chain material (which is usually hardened steel). <S> Note that bicycle chains do get longer due to wear on the material. <S> So something else must have happened to make the chain sag. <S> The most likely explanation is that the back wheel was pulled out of its dropouts, as indicated in BillSkiCO's answer. <S> It is also possible that the chain was already sagging before, you just did not notice. <S> On bicycles without a derailleur, chains can sag quite a bit without causing problems. <A> When you stretch a chain the distance between pegs become longer than designed. <S> Even fatal chain stretch cannot be easily identified by looking at the chain. <S> There are very simple yet accurate chain scales used to identify whether the stretch is none (new chain), fair, acceptable, "replace the chain", "replace all chain and sprockets". <S> Another way to estimate the chain stretch is to try to lift the chain from the sprocket. <S> The further you can lift it, the more stretched chain you have. <S> One can see the chain is stretched far above the "replace the chain ASAP" level when the teeth on small sprockets are no more symmetrical and become worn from the rear side (upper teeth of the rear sprocket). <S> When the chain starts skipping over the teeth, whole drivetrain it worn out and the chain still looks quite good to many people and is still very strong in tension and the peg-to-peg distance is stetched in orders of tenths of milimeters. <S> Another reason for not-stretching a chain is the momentum one can produce on such bike. <S> The crank arm is shorter on kid bikes than on the "full size" bikes. <S> Therefore the tensile force you have applied to the chain was lower than you are able to apply on your bike. <S> Since you were able to load the chain with weaker forces and even hard stretch will be negligible to wrong setup the only option left is that you have moved the rear wheel a bit front. <S> Realign it, as others already suggested, and tighten it. <S> It is worth nothing to get the chain measured for the wear, though.
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This is often referred to as "stretch", but that is misleading - the chain does not lenghten due to being pulled, like a rubber band, but because the friction in the links wears down the material. Bicycle chains are very strong (and chains on children's bicycles are usually similar to chains on adult bicycles).
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Rain Booties that go over Cleats I use clipless pedals for bike commuting, and I'm looking for suggestions on waterproof "booties" that can go over a pair of cycling cleats. I can find some products on-line, but can't ever see the bottom of the "bootie" whether it covers up the cleat or not! What's the name of the thing I'm looking for, so I can search for them? <Q> Shoe covers/booties <S> will help keep your feet dry, but there's really no such thing as "waterproof" shoe covers/booties. <S> The best of them merely delay your shoes filling with water for maybe 20 or 30 minutes in any decently heavy rain. <S> Even if the material itself is waterproof, there are too many ways for water to get in. <S> First, water is going to run down your legs into your shoes. <S> Shoe covers won't help that much if at all. <S> You can help keep water out of the tops of your shoes by wearing tights or some other clothing that fits over your shoe tops and directs water outside the shoes. <S> But even that won't keep all the water out. <S> ("Hey, I'll just wear waterproof pants!" <S> isn't an answer - after a few minutes that can be like cycling in a sauna because waterproof works both ways...) <S> Water is also going to get in through the soles via the cleat holes, unless you have specially-designed shoes such as "winter cycling boots" that are designed not to have this problem. <S> Or don't have cleats at all... <S> And even then, if you don't have fenders with a good mud/spray flap on the front, the spray from the front wheel will rapidly soak your lower extremities anyway. <S> Spray enough water onto your shins and your shoes will be filled no matter what they're made of and no matter what you do to keep water out of the shoe tops. <S> Then, you need to prevent water from coming up through the sole - and that requires special shoes, or not riding with cleats at all. <S> Shoe covers/ <S> booties are in the "keep your feet from getting totally soaked for just a few more minutes" category. <S> If that's all you need, that's fine. <S> But they won't keep your feet dry. <S> To do that, you need a lot more help. <A> Cycling shoe covers always have holes for cleats. <S> The clipless mechanism depends on exact fit between cleat and pedal and doesn't work if there is anything between. <S> If you do not need foot retention, there is no need to play with shoe covers. <S> Just use waterproof shoes (with gaiters to prevent water running down your legs from getting into shoes, the waterproofness works both ways), waterproof socks (great if your shoes holes where the water can drain out), wellingtons or whatever fits the weather and your needs. <A> We don't do product rec here, but basically most bicycle clothing companies and companies that does something related to shoes sell shoe covers. <S> These generally have a little hole for your cleats -- even if you mistakenly bought one that did not have a hole somehow, you could fix this relatively quickly with a pair of scissors and possibly a sewing kit/some tape. <S> Depending on where you are, using sandals (warm and wet; you can get clipless ones; dry quickly) or hiking boots/waterproof shoes/galoshes (cold or warm and wet; use plain old platform pedals with good grip with regular shoes, or buy waterproof/weatherproof cycling shoes for clipless; right shoe will be temperature dependent to some extent) may be better; the main issue with covers is that you have to carry around one more thing, and they can wear down relatively quickly from putting your foot down. <S> For commuting, waterproof shoes/boots/galoshes are probably a good way to go, particularly if you have to walk somewhere during a rainy day, anyway.
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So, if you want to keep your feet truly dry, you need to start with fenders with a good mud/spray flap to keep most of the water off your feet and legs in the first place, and leg coverings/tights/pants that direct most of what does get on you away from getting inside your shoe tops.
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All gears shift smoothly, but won’t shift into 1st gear/large cog. Help? So I was tuning my newly acquired bike today and working with all 8 gears on the rear derailleur. I managed to properly set the high limit screw as well as cable tension so all gears shift smoothly from 2-7. However, when I try to shift to 1st gear, the derailleur won’t move and neither will the shifter. The cable tension is too tight. I also tried manually pushing the derailleur by hand and I can jusssssttttttt get it to shift into first, but it requires a lot of pressure. The only effect adjusting the low limit screw has had is that if it is too loose, it won’t shift from 3rd to 2nd. Tightening it anymore doesn’t shift it from 2nd to first. I briefly inspected for alignment and from eyeballing it things look OK, but I am not too sure. What are some things I can do or try and what should I be looking at if something needs fixing? Thank you guys for your help. <Q> First thing to do is disconnect the shift cable from the derailleur and check three things: <S> The derailleur will swing through its full range <S> The shifter will click through all gears. <S> The cable travels freely. <S> You should be able to get hold of the shifter and derailleur ends of the cable and pull it back and forth. <S> If anything is hanging up or jamming, that is where you need to look for problems. <S> I'd also check the shifter cable routing and make sure there are no cable and housing are where they should be <S> and there are no kinks. <A> You need to either loosen the hard-stop screw for the high limit or the low limit depending on if it won't go into the biggest cog or the smallest cog. <S> I would loosen the screw one-turn and see if it helps. <S> Fine tune the adjustment from there. <S> The screws are easy to turn if you move the derailleur slightly away from the stop. <S> You might also experience not being able to drop into the smallest cog if your cable is too tight. <S> If this is the case, then loosen the cable by turning the barrel-adjuster on the cable in. <S> Here's a decent tutorial: http://www.madegood.org/bikes/repair/set-a-limit-screw-on-a-rear-derailleur/ <A> First off: Your description "The cable tension is too tight. <S> " is ambiguous. <S> Do you mean that loosening the cable would allow the derailer to move sufficiently? <S> (And that it does so <S> if you disconnect the cable?)Or do you mean (and that's what I suppose) that it is very tight despite the derailer <S> not moving?(I know this should be a comment to the question, but I seem not allowed to do so. <S> If anyone else can, feel free to move.) <S> To your question: <S> Given that the cable is really tight and the derailer is not moving nonetheless, it is most likely blocked and most likely by the teeth of the biggest sprocket. <S> Look carefully, comparing how the pulleys align with the smaller sprockets. <S> To remedy, carefully hold the derailer and twist it clockwise around the mounting bolt. <S> If it moves, you found the culprit. <S> Other possible causes include: your hanger is bent. <S> Try to check whether the pulleys are parallel to each other and to the sprockets. <S> the derailer is blocked by other means. <S> your chain is too short. <S> (Did you switch to the smallest chainring?) <S> the cassette is mounted too far inside. <S> Since you are talking about an 8-speed cassette, that should hardly be possible, however. <S> (Also, the derailer should be able to move all the way to the spokes.)
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From what you describe, it seems that pushing the derailleur inwards manually to get it onto the largest sprocket was tightening the shifter cable - that is suspicious, it should have loosened the cable. There could be debris, twigs or such inside it.
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Old Shimano Altus Hub disassembly. Clockwise or counter clockwise? I hope to squeeze a bit more life out of this old Shimano Altus hub and apart from having to build my own tool: Do I have to turn the inner part with the two notches clockwise or counter-clockwise? Edit: Thanks to you guys I just needed to buy an Allen wrench for 2.75€. Turns out the small tool shop is much cheaper than the big 'we sell everything' construction markets. The hub needs a thorough cleaning and should be fine after that. <Q> The part with the two notches is left-threaded, so clockwise to loosen from the perspective of your picture. <S> It should be noted that these are quite the can of worms once apart, and cleaning/lubrication can be done pretty effectively by taking the whole freehub body off using the 10mm internal Allen wrench flats (poke a 10mm Allen into the hole in the center of the freehub; that part is normal threaded). <S> Then on the back you'll find a rubber seal. <S> Carefully pry that out and keep track of its orientation. <S> Then you can easily blow or drip air or whatever lubes/ <S> cleaners you want into the mechanism. <S> The one thing that can't be done this way is take advantage of the seldom-discussed cassette play adjustment that Shimano freehub bodies have. <S> To do that you remove one of the thin shim washers you find inside the freehub internals. <S> You don't want regular bearing grease in there because it can gum up the mechanism. <S> The main thing I know that works is a thin layer of Slick Honey or similar very light grease. <A> On some hubs the attachment bolt that fixes the freehub to the hub also locks this bearing cup, make sure to loosen or completely remove it before attempting to unscrew the cup to avoid destroying its threads. <S> While often not necessary to overhaul (especially given that the bearings don't take much load and in almost all cases you won't get hold of spare pawls), it is actually not that hard to reassemble. <S> Make sure you disassemble slowly and keep the bearing balls of each bearing separate (25 balls, each). <S> There is also a video on youtube that shows the process. <A> While this old hub doesn't have that many parts, the presumably 50 balls have a tendency to vanish. <S> That's the reason why right now I have only 49 balls, feeling slightly dumb ( :
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If you do take it apart you must answer the question of what you're going to use to keep the ball bearings in place when putting it back together that's also not too thick for the purpose. It is left-threaded, turn clockwise to loosen. One thing you definitely want to do is to disassemble it inside a white bowl.
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Gears shift perfectly when suspended on rack, but not on the ground? So I had recently solved some issues I was having thanks to the community. I re-tuned my bike on a suspended mount and everytning looks great. On the ground, all of the gears work smoothly except for shifting into 8th gear (8 speed rear derailleur). The chain hangs on 7th and won’t jump. On my bike rack it shifts perfectly after properly setting the high limit screw. The only way I’ve gotten it to work on the ground is backing out the high limit screw more (small turns), but the shifting is sort of a jolt and it occasionally overthrows the chain and derails it (...bad joke). Any suggestions or tips on what to look for? Nothing appears bent, bolts are tightened, wheel is true, and bike is tuned. I’m seriously scratching my head. Thanks <Q> While I'm not sure this qualifies as an answer, because with such questions there is usually a lot of guessing, your issue sounds like a flexing issue or a worn rear-hub. <S> The flexing could happen because of your weight (maybe fatigued frame? <S> or just flexible) resulting in slightly changed geometry while riding vs suspended mount. <A> Running out of stock of useful crystal balls it is hard to guess what the true cause is, here. <S> But here are some things to check. <S> It partly depends on whether you use a "low normal" ( <S> without cable tension the cage is pulled to the sprockets with more teeth) or "high normal" (the spring pulls the cage to the sprockets with less teeth) rear derailer. <S> If it is the latter, you can try disconnecting the cable to see whether it shifts to end. <S> If not, re-adjust the limit screw. <S> If you then need to loosen the screw so far that the chain is frequently dropped off the end of the cassette, most likely your derailer hanger is bent. <S> In this case the pulleys are not parallel to the cogs, throwing the chain off the cassette. <S> If however it works properly disconnected, the might be friction in the cable housing that pulls the derailer inwards; read on. <S> In case you use a low normal derailer, don't disconnect the cable. <S> You may want to check the same points as mentioned above, but before you have to make sure the cable tension is right. <S> There might be just enough friction in the cable housing that some flex in the frame accounts for insufficient tension, especially if the shifter cable is routed around the bottom bracket. <S> Try increasing it a bit. <S> You may increase it until the other gears don't shift properly anymore, then back down slightly. <S> Note that if increasing the tension indeed fixes shifting to the highest gear <S> , this will probably not solve all your shifting issues. <S> Your trade off will likely be non smooth shifting to the lowest cog. <S> Replace the cable housing (and the cable) to fix. <A> When you say 'on the ground' I assume <S> you mean you are riding the bike and testing the shifting, and when the bike is off the ground you are spinning a crank with your hand. <S> The major difference between riding and spinning the crank manually is the forces the drive train has to transmit. <S> I.e. shifting is effected when there is significant tension on the chain. <S> I suspect worn chain and cassette. <S> If the bike has significant mileage check the chain stretch for elongation and the sprockets for signs of wear. <S> I'd also check the state of the derailleur jockey wheels. <A> I'd start with the derailleur hanger. <S> Usually fixes my problems when everything seems okay, but the bike still doesn't shift well.
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A worn rear hub could cause a wobbling or light tilting in the cassette while under load. I would also check the cables while the bike is mounted on the stand and see that the clamps or the bike position (handlebars sitting at a hard angle, pulling on cables) are not somehow affecting the tension in the derailleur cable.
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110mm crank on 73mm BB shell I have a roadbike with a 73mm BB shell and I recently bought a Tiagra compact crankset that has a 110mm bolt circle length. However, I can't get enough of it to come out the other side to properly attach the left arm of the crank. This is really upsetting because, as far as I can tell, Shimano only makes 110mm length cranks for compact (double) chainrings. The only solution I see is getting a new triple crankset for about €100 and this would mean I have to change my STI shifters and possibly the front derailleur as well... Are there any other options? EDIT:You are right i was confusing BCD with spindle length, the problem is that the 110mm spindle wont come out enough to attach the left arm, triple cranksets do have slightly longer spindles tough. <Q> Tiagra is a road group. <S> Road bikes typically have a 68 mm wide bottom bracket shell, and mountain bikes have 73 mm. <S> The wider BB shell is used to give a proper chainline with the (usually) wider rear axle spacing (OLD) and will result in a wider q-factor (distance between pedals.) <S> This frame is an unusual build with the 73mm BB and the 130mm OLD, perhaps to take advantage of the smaller chainring sizes available in MTB cranksets. <A> Other answers have suggested solutions, but I think I know why the situation has occurred. <S> The entry-level model of the Attain (and the Axial WLS) use a 73 mm threaded shell, and use a 73 mm cartridge bottom bracket like the BB-ES300. <S> These offer a choice of axle length and use Shimano Octalink cranks, so the axle length can be specified to suit the road crankset you are replacing. <S> Threading in a Hollowtech II bottom bracket to the 73 mm shell makes the assembly too wide for the (110mm) axle of a road crankset <S> so it won't fit. <S> Higher spec models use a 73 mm press fit bottom bracket shell. <S> This has no outboard cups and therefore allows the assembly to be the correct width for a road (HTII) crankset. <S> Unfortunately this all means that your frame will not accept the road style Hollowtech II crankset and the upgrade is off the table. <S> You could explore the use of mountain cranksets but as you appreciate the shifters and derailleurs might not be compatible, or the gearing might not suit road riding. <S> The other risk would be frame clearance. <S> Let us know if you experiment and get it working <A> You are confusing two different measurements. <S> The bolt circle diameter (BCD) is the diameter of the circle the bolts that hold the chainrings lie on, not the length of the axle. <S> In general a crank needs to be matched to the type of bottom bracket you have. <S> There are many bottom bracket types and selecting a compatible crank is confusing. <S> First step is to compare your new crank to the old. <S> If the axle is shorter then the new crank is a mismatch. <S> If the axle length is the same then there may be a spacer that needs to be removed. <S> Adding a picture to your question will enable someone here to help. <S> Also add the exact model of the new crank (and the old one if you know it). <S> UPDATE: <S> The axle measurement as shown in your pic was indeed 110mm <S> (I think it's a co-incidence that it's the same length as the BCD, apologies for to misunderstanding and miscorrecting you). <S> My BB shell is 68mm - the common standard for road bikes. <S> So you have a mismatched shell width and crank. <S> This answer may help explain what's going on here. <S> Incidentally, if you have a 'road' Hollowtech II BB for 68mm shells <S> the inner sleeve will not be bridging the bearings which is a bad situation. <S> I’m suspicious of the B.B. shell width given in the pic. <S> Cube Attain is a road bike and according to the Cube website all the models have road cranks. <S> Did you get a ‘mountain’ style BB? <S> Those come with spacers and fit both 68 and 73mm shells. <S> If so and you installed it with spacers <S> the BB would be too wide. <A> The BB for Cube attain 2016 is Shimano BB ES300 73mm <S> x 118mm. <S> You can look for ISIS or Octalink BB/ crankset.
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If you need to get a different crank you’ll need to figure out what type of bottom bracket you actually have - one for threaded shells or one of the press fit types. You need a mountain bike specific crankset. I checked the axle length on an older 105 crank I have lying about, and the shell with of the bike it came out of.
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Making a left hand turn as a commuter I am thinking about commuting to school on my bike and wanted some advice on it. I do live in a very bike friendly neighborhood, but the thought of turning left on a 40mph road (no stop lights nearby and people speed) does scare me a bit. What are your recommendations for turning left?Thank you in advance! <Q> There is a dedicate bike lane Stay on the bike lane and, if it also goes to the left where you want to go, follow it. <S> Avoid cutting corners just to shorten your way and signal in time your intention (also other fellow cyclists prefer to know where you are going in advance). <S> If the lane doesn't turn left where you would, follow next point. <S> You drive in the normal traffic <S> The normal procedure to turn left (assuming you ride on the right) is to get to the center of the lane and then turn as soon as no vehicles are coming from the front. <S> Wait some time with the hand out, check that no vehicles are approaching at your left and slowly but steadily move to the left. <S> Complete the turn as soon as possible. <S> Alternatively, cross at a pedestrian crossing (dismounting from your bike if necessary). <S> In all cases: Be visible : wear high visibility gears. <S> Bikes are small and easily slip past consciousness in traffic. <S> Be assertive with your movements and don't zig zag. <S> You don't want the drivers to assume you are just erratic in your cycling. <S> Listen and read the traffic . <S> Learn to understand the context around you: are the drivers calm? <S> Do you see anybody who is distracted or plainly a jerk? <S> Don't wear headphones or fiddle with your smartphone while cycling <S> Be fit and avoid cycling if you are not in condition of doing it. <S> You want to be sure you can react promptly on the road <S> last but not least Safety first <A> Generally speaking, in the US, in light to moderate traffic, and where there are no bike lanes or other provisions for bikes <S> : Plan your turn in advance. <S> "Dawdle" on the shoulder to let any burst of traffic pass. <S> Signal your turn with an outstretched left arm. <S> Do this repeatedly, when you can safely take your arm from the handlebar. <S> If there is only a single traffic lane, move to the center of the lane. <S> If there are multiple lanes, move, in steps, from the right lane until you are in the left lane. <S> If the left lane is a turn-only lane, position in the right side of it (but not so far right that people will try to squeeze through on the left), otherwise in the center. <S> Continue signalling. <S> Wait for an opening in the oncoming traffic. <S> This may require some more "dawdling": It's' generally easier to make the turn if you "stall" by moving slowly rather than to getting right to the intersection and stopping. <S> Signal some more, then turn. <S> If all else fails, stop on the right shoulder, dismount, and walk across. <S> Where there are bike lane markings there may be different rules -- be aware of local rules. <A> When walking, the shortest route is normally the fastest. <S> When riding your bike, you have a lot more speed and can go 10-20% longer while still being faster than a direct route. <S> So explore options <S> ... look for A bridge <S> An underpass/tunnel an intersection with traffic lights to break up the flow of the road to cross a longer way around that has a better overall "feel" https://www.strava.com/heatmap <S> can show you where people ride in your area, so explore and see if there's something of which you're unaware. <A> As long as you have decent visibility, turning across a road with fast-moving traffic shouldn't be too terrible once you get used to the idea. <S> If you can safely move into the turn lane, great.
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If you can't cross lanes to get to the turn lane safely, then just stop on the shoulder and wait for a pause in traffic. As you will soon learn if you do commute on your bike, safety is mostly about being visible to motorists, being aware of what's coming behind you, and taking the safest route. I highly recommend investing in a good helmet and a mirror, always wearing highly-visible clothes, and scouting out the best route beforehand. What you do strongly depends on the road layout: Therefore put your left hand out in advance and make clear you want to move left.
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Installing a new Shimano compact crank on an older bottom bracket? I would like to know if I could install a new Shimano compact crank on an older bottom bracket that has a center bolt extraction system? Do I need to change the spindle in the bottom bracket? Do I need a new crank extraction tool for the new crank system?Thanks Mark <Q> This assumes you mean the BB is square taper (one of many examples). <S> Most crank pullers will do square taper, but you often need to use the tool slightly differently, such as by removing a cap. <S> You probably can't change the spindle anyway, but you should be able to buy square taper cranks to suit you, and if not a new BB isn't too expensive. <S> The process is essentially the same for all vaguely modern cranks . <A> You'll need to remove the old bottom bracket completely and replace it with a Shimano BB. <S> The make and model of your bike and the model of the crank with some pics are necessary to say any more than that in terms of specifics. <A> You have a couple of options. <S> Replace the crank only, or replace both BB and crank. <S> If you replace just the crank you need one that is compatible with your existing BB, which is presumably a cartridge type with square taper (or possibly Octalink) spindle in a threaded shell. <S> You don’t need to limit yourself to Shimano, there are a few brands that offer square taper cranks. <S> If the bike is old or well used the BB may need replacing, in that case you may also look at an external threaded BB and matching crank. <S> Again, you can look at both Shimano and other brands.
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New Shimano cranks do require a new crank removal tool.
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Are disc brakes weak? And what is "bedding in"? I've owned a couple of department store bicycles in the past with caliper brakes and I set the brakes up properly so when I squeezed the brakes the bike stopped pretty quickly. I test-rode a bicycle from a bike shop a couple of days ago which had disc brakes, and it was just so slow to stop the bike, it seemed like the brakes were so weak. I checked the brakes on the spot by standing next to the bike and squeezing the front brake and pushing the bike forward, and there was no slippage, and same with the rear wheel. So I think the brakes were set up correctly, they just seemed to have no stopping power. I asked the clerk about it and he said they would need to be "bedded in". I couldn't understand what he was talking about, but is it normal? And why can't I get a bike that's ready to go from when I buy it. Do I just buy a bike with weak brakes and use it for a while and after a few days the brakes will work better after it grinds a groove in or something like he said? Or were the brakes not set up correctly? <Q> Bedding-in is a common process with new disc brake pads. <S> Disc brakes were developed much earlier for motorcycles and cars, from which the technology and the terminology has been transferred to MTBs: see https://ebcbrakes.com/articles/motorcycle-bed-in/ and http://www.centricparts.com/files/White%20Paper%20Revisions%204-2012/Centric%20White%20Paper%20C3-2012-Bed-In%20Stock.pdf <S> Bedding-in is a process in which both the pad surface microstructure but also the surface composition of the rotor is affected. <S> During the run-in a very thin layer of material is transferred from the pads to the rotor. <S> This surface deposit increases the brake power significantly. <S> However, even when the brake pads are not yet bedded-in, a disc brake should have more stopping power than a rim brake. <S> So I wonder whether the surface of the rotor or possibly the pads have inadvertently been poisened by a lubricant. <S> Ask the seller to clean the rotor with alcohol. <A> I just searched and found this: https://www.sram.com/sites/default/files/techdocs/gen0000000004358_rev_a_avid_brake_pad_advancement_product_installation_update_0.pdf <S> This is from SRAM's website. <S> They are a prominent disc brake manufacturer: <S> All new brake pads and rotors should be put through a wear-in process called ‘bed-in’. <S> The bed-in procedure, which should be performed prior to your first ride, ensures the most consistent and powerful braking feel along with the quietest braking in most riding conditions. <S> It is this transfer layer that optimizes braking performance. <S> They seem to think that if you accelerate to a moderate speed and then brake down firmly to walking speed about 20 times, then accelerate to a faster speed and brake down firmly to walking speed again a further 10 times, that this will be enough. <S> From my own experience, brand new disc brakes are not as strong as you'd want them to be, but after a ride or two they pick up in performance and are a lot stronger than they were at the start. <S> To answer the second part of your question (why can't I buy a bike that is ready to go): Because it would cost more. <S> With modern manufacturing techniques being so consistent, the bike probably hasn't actually been fully assembled before you do it or get it done at the store and ride it. <S> They would have to fully assemble it and either take it for a ride or mount it in some specialised machine in order to bed the brakes in which all takes time and money. <S> This might cost an extra $20 on the bike price. <S> For something which is really only a minor inconvenience it's not really worth it to most people. <S> Bedding in of brakes is also just generally something that's accepted, even for car disc brakes. <A> Why can't I get a bike that's ready to go from when I buy it? <S> I would say you can. <S> Ask your LBS to bed the brakes before you'll buy it <S> , that is the service that your bike store is in the position to provide over a department store or online retailer. <S> You didn't specifically mention, in your post, if the disc brakes were hydraulic or cable. <S> One of my kids has a bike with a cable disc brake and it does not brake nearly as well as a similar bike with a cable rim brake and far worse than the bikes I have with hydraulic discs.
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The bed-in process heats up the brake pads and rotors which deposits an even layer of brake pad material (transfer layer) to the braking surface of the rotor.
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Gates Carbon Drive vs single-speed chain, long term lifespan and maintenance I'm looking to get a new bike which will require the smallest amount of maintenance. The bike will have an internally-geared hub and I have the choice of single speed chain or belt drive. I have been looking at the Gates Carbon Drive and investigating maintenance costs: A CDX belt is around 8 times more expensive than a chain where I live.Also the chainring and rear sprocket are round 4 times more expensive. What is the lifespan of a Gates belt against a Single Speed chain? I've looked up online but peoples opinions are conflicting. Some say in similar conditions a belt will have a similar lifespan, while others claim up to 10 times longer use.What is the actual lifespan of a belt compared to a well maintained single speed chain in similar conditions? I understand a belt drive is not maintenance free but much less than a chain.If a belt can last 4 times longer than chain then I would consider this worth the investment. Also is there an expected life difference between 11 speed and single speed chains? As comparison to my current bike. <Q> On single sped vs. 11 speed chains. <S> SS chains will have wider side-plates and therefore larger bearing surfaces. <S> The big difference is that SS chains are run with the chain ring and sprocket aligned. <S> Derailleur chains spend most of their time being run with the chain ring and sprocket offset <S> so the chain has to cope with lateral forces. <A> I’ve run a gates CDX belt on an AWOL with a Shimano 11 spd internal hub for over 10,000 miles, much of that on wet or dusty trails. <S> The front sprocket is aluminum and shows considerable wear, but the rear stainless sprocket and belt show very little visible wear. <S> I’m getting ready to replace the hub (bad 6th gear), so I’ll also replace the front sprocket and belt. <S> Who knows, the belt may go another 10k, but I’ll let someone else do that test. <S> Ease of maintenance sold me on the belt. <S> No one asked, but what about tension? <S> Too tight it will squeak and too loose it will slip. <S> Just barely tight is what I would describe. <A> I have a CDX setup and IGH with a bit over 4000 km. <S> It's on a mountain bike that I commute with and ride on really muddy trails. <S> I love the no maintenance aspect, I've only hosed it off a half dozen times, when it makes noise. <S> I think that the road salt, sand, and mud are really hard on both cogs, I see most wear on the rear. <S> As far as tension, I put a 10 lb weight on the belt, midspan, then place a straight edge, from cog to cog, measure in between deflected belt, to straight edge. <S> Gates says 10-12 mm, I find 15-18 mm causes less drivetrain noise and doesn't skip. <S> I also use a belt snubber, placed close to but not touching the belt, as per Rohloff. <S> At 10-12 mm, I could feel the added drag. <S> Not noticeable at 15-18mm. <S> I'm hoping to get 6000 km before replacing both cogs and belt at the same time, as a set. <S> I don't think that you gain anything from changing just one piece, they wear as a set. <S> Last year, I covered 8000 km with 8 chains, 2 cogs, and 1 chain ring, my riding conditions are really tough on chains, and I would clean/oil every day. <S> With that math, 1 belt equals 6-8 speed KMC chains, the good ones. <S> All things considered, I'll take the belt drive, thanks. <S> Maintaining a chain, in winter, and after every muddy singletrack ride sucks. <S> Now I usually just grab my bike and go <S> , it's perfect, for me.
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Don’t run a belt too tight, it will wear out your BB bearings (I’ve done that test). A SS chain should last a lot longer than a derailleur chain. In my opinion, the dirty belt seems to spin much better than a muddy chain. Price is not much of a factor, when the positive aspects are considered.
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What happened to double eyelets? Whenever I talk with old wrenches about wheelbuilding, they always seem to talk about double eyeleted rims as the pinnacle of strength and quality. However, it seems most modern, high-end rims have no eyelets at all, let alone doubles. The only models still in production that I know of with double eyelets are basically 15+ - year - old designs (Ambrosio Nemesis, Mavic OP & A719). While the principles behind double eyelets make sense to me, and they definitely make building a wheel easier, AND they look super cool, I'm sure there is a reason they are no longer widely used. Is it because new stronger alloys and fabrication techniques make the extra weight of double eyelets unnecessary? Is it something to do with alloy nipples (I can't see how this would be the case)? Do you miss them? Do you wish they were more common in new designs? If anyone has some technical data on the benefits of double eyelets please share!thanks. <Q> and it seemed like Open Pros and A719s were the only rims with them. <S> There are now also good DT, Araya, and H+Son rims with them, and maybe some others. <S> They are not extinct. <S> V-section rims, which have of course risen in prominence, tend to have (or can easily be made to have) a concentrated section of material at the spoke hole, which accomplishes a similar thing in a cheaper and potentially more weight-saving manner. <S> V-section rims tend to not have fatigue cracking issues unless they're either garbage, way over-tensioned, or way under-weight for their use. <S> For the most part you don't really see it on the nicer aluminum V type rims. <S> Double eyelets add weight and cost, are not immediately function-critical, and, most endangering of all, are invisible to consumers. <S> So they have a rough time being something that manufacturers care to mess with. <S> One of the major things that's happened with rims in the last decades is that materials (i.e. fancy niobium alloys) have gotten stronger but not more fatigue-resistant, or at least not at the same rate, and cross-sections have gotten bigger and stiffer with thinner walls. <S> Those are some of the reasons there's more emphasis on building to a tension spec than there used to be. <S> With a classic road rim, however much tension you added that the rim could still take structurally, you could feel safe knowing that it could also take it reasonably in terms of fatigue resistance. <S> It was also easier to accidentally taco them in the stand from adding too much tension. <S> There are rims running around now that are much stronger and stiffer, so you need to cap out your tension even though the maximum strength capacity hasn't necessarily been reached. <S> From a design perspective, double eyelets can help you get access to more of that strength by adding fatigue resistance. <A> From Schwalbe's FAQ on tubeless : Tubeless mounting is usually impossible for [...] rims with double eyelets. <S> In these cases, it is not possible to ensure airtight sealing with the rim tape. <A> Actually, those "double eyelets" should rather be called "sockets". <S> They bridge the two horizontal walls, distributing the load, adding stability. <S> See also Jobst's explanation here . <S> He also states: <S> Rims have eyelets the same as eyelets on shoes or clothing. <S> Rims can also have sockets that bridge inner and outer walls of a hollow rim and are held in place by eyelets. <S> [...] Eyelets are generally used to prevent galling of the aluminum rim when highly loaded nipples are turned, regardless of their material. <S> In fact, I just unwrapped one. <S> Sockets might be impractical on very deep V-shaped rims. <S> They would need very high sockets that probably would be not sufficiently sturdy, in particular as their material of choice seems to be stainless.
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The main thing they do is spread the load to both walls of the rim in order to reduce the risk of fatigue cracking. It's worth noting that in a sense, when a box-section design is what you want, double eyelets actually are more relevant than ever. Funnily, we actually have many more new rims available with them now then in the early to mid aughts when they were at a low point They can't be used with tubeless tires. Socketed rims are still readily available.
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How to fix a metallic bicycle basket to the back rack? I've been using plastic cable connectors , as can be seen in the picture below, to hold a bicycle basket fixed to the rack. However, they loosen up every couple of months. What would be a better solution (easy to do, and more durable)? <Q> I would look at 3~5 small aluminium fish plates in the basket, and small saddle clamps under the rails. <S> You'd need two small stainless steel bolts and nylock nuts per plate, or some other way to reduce vibration. <S> Suggesting Stainless Steel to avoid rust, or you could just use grease. <S> This will make undoing the bolts hard later, and rust may mark things you put in the basket, like cloth. <S> This suggestion would not be easier, but it will be a lot more durable. <S> There are metal zip ties, but they will have the same loosening problem, which is exacerbated by the small radius they have to clamp around. <S> Some ideas: <S> Imagine the above but with the bow replaced by and some bolts with the threads facing downward. <S> You could use old spokes or other metal wire. <S> Spokes are hard to bent with fingers so pliers might be required. <S> Any sharp end could poke a hole into load items in the basket too. <S> I've got a box of thousands of galvanised concrete reinforcing tiedown wires that can be bent by hand. <A> I have a fair bit of experience with these baskets, and can tell you with confidence that the mesh will not hold up to any force that exceeds that of a plastic zip-tie. <S> However, you might just want to try heavier-duty plastic zip ties with a metal pawl. <S> Make sure they are wrapped around the main frame of the basket, not just the mesh, and pull them as tight as you can. <S> Also, if you insulate the contact points betwen the rack and the basket with a bit of rubber or leather (old inner tube works great), it will dampen a lot of the vibration that is probably causing the ties to come loose. <A> I would either use some dedicated set, like this one: Basil crate fixing set <S> (picture comes from their webpage). <S> Or I would fabricate something similar using 4 penny washers (on top of the basket) with 4 M4 or M5 bolts with nuts and 2 metal (aluminium) strips for under the carrier rack. <S> Perhaps 2 bolts with penny washers and 1 metal strip along the rack would be enough. <A> Ask your local bicycle store for a "basket fastener" or "basket holder" <S> - they should be able to help you. <S> The nice thing is that in addition to fasteners that are screwed in place, you can also get fasteners that can be detached by pressing a button or lever - that is useful to detach the basket if you want to use it for shopping, or if you temporarily need the rack for something else. <S> I personally use the KORBfix (non-detachable) by Rixen & Kaul (German company, but also sold e.g. in the US) . <S> For more information, go to the manufacturer's site , and enter "korbfix" in the search box. <S> Rixen & Kaul also offer a range of detachable fasteners, under the brand name KLICKfix .
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While you can certainly improvise something using metal fasteners, you could also consider buying a dedicated basket fastener .
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Is movement in my bottom bracket an issue which requires attention immediately? TLDR; my bottom bracket has movement when it shouldn't but no other issues / sounds / clunking. If I'm riding a few miles a day, is this likely to break catastrophically, or will it last another year or two issuing the odd warning sign? This is different to the question: Riding on a failing bottom bracket - what could possibly go wrong? as mine doesn't experience clicking. I have an old (20 yrs) mountain bike. The bottom bracket has play in it, one side can move up and down 1-2 mm - I am guessing this is simple wear. There are no other issues, no creaking, no stiffness, other than the movement. I cannot replace the bb unfortunately, tried to remove the crank arm and it pulled the thread out instead of the arm! I also suspect I'd have issues getting the bb out too. Bike is worth next to nothing, but this is an advantage as it makes it less likely to be stolen. Assuming this is simple wear, will I get warning signs before it dies, or will it just unexpectedly die on me? I understand there is no definitive answer to this, given the lack of info/data on the issue, but would appreciate answers from those with experience of this. Edit: this is a sealed unit, so one side screws into the frame and the other has a plastic screw(?) to hold it in place. No adjustment of cups is possible as far as I am aware. To clarify, there are no sounds coming from the bottom bracket. <Q> I'd suggest you try tightening the Non Drive Side cup and see if there are any improvements. <S> You don't even need to remove the crank for this. <S> The right tool will just slip on, or you can get away with a big spanner and some plumber's sliding jaw grips. <S> If this helps the problem even a little, a proper clean and regrease will help a lot more. <S> The risk in not doing this is that there will be damage done to the cones in your BB, and if metal flakes off the inside surfaces where the bearings run, then its toast and you will need a replacement. <A> <A> 'Normally' the answer is 'Its worn out, you should replace it". <S> This you already know. <S> Looking at this from several aspect is the key to making the decision. <S> The movement will cause the chain rings to slop around. <S> A small amount won't affect things too badly, but eventually you will suffer poor shifting and chain slipping. <S> The chain will start to slip as the chain rings move in relation to the derailleur. <S> Worst case is a chain break, and very worst case would be the chain dropping off the cassette into the spokes and locking the rear wheel (although a properly adjusted rear derailleur should prevent this even with lots of slop in the chain rings). <S> ,Eventually it will become unsafe. <S> I presume by "pulled the thread out" you mean the crank extractor stripped the crank arm thread. <S> I had this happen once and found the cheap extractor was undersized. <S> I was fortunate enough thread <S> was intact that a workshop quality extractor had enough to pull the crank. <S> If the thread really is stripped, you will need a new crank arm. <S> The bike as is has very limited life - I would not expect many more miles before it gets so sloppy its not rideable. <S> Either retire it or look for used parts - a donor bike, a mate with a box of bits, or a local bike coop.
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If there is play in your bottom bracket it means that the bearings are loose or worn out, it should be repaired soon because it will influence the whole drivetrain negatively, like sprockets and chain. A cartridge bearing is relatively cheap these days, and is well worth doing even on a beater bike.
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Is it worth buying carbon fiber road bike for short commutes? I'm planning to use a bike for rather short commutes (max half an hour), will the carbon fiber be noticeably more comfortable than aluminium one? <Q> Comfort isn't really an issue for a 30-minute ride, as long as the bike fits. <S> For a commuter bike, I'd be much more worried about theft and damage, unless you have somewhere secure to park the bike at work. <S> If you are worried that aluminium will be too harsh, you're probably wrong <S> but I'd consider steel instead, rather than carbon. <S> Or just put wider tyres on it. <S> I've ridden rigid aluminium hybrids with 28mm tyres and had no comfort issues at all. <S> Any good bike shop should be happy to let you take a test ride of at least half an hour on any bike you're thinking of buying. <A> If you are going to be commuting regularly so that you rack up some miles, in different kinds of weather, I think it's better to buy an aluminum frame bike and spend the saved money elsewhere. <S> Also, remember the cost of replacing tires, chains and cassettes. <A> As others have mentioned, for such short rides comfort will likely not be a major concern in the same way it would for endurance events, "bikepacking", or even racing. <S> That's not to say you shouldn't consider comfort at all - a bad saddle or bad bike fit can make things hurt in a hurry. <S> But these are things that can be easily adjusted to make any one of hundreds of bike models work, and you shouldn't need to optimize your comfort beyond pinning down those basics. <S> That said, I wanted to address the underlying assumption within your question: that some frame materials are fundamentally "more comfortable" than others. <S> While it is true that it is generally easier to make some materials feel comfortable, in the end comfort, or whatever performance metric you choose to focus on, is the result of complex interactions between the materials, the geometry (both rider geometry and tube shapes), and the construction of the frame. <S> With clever enough, or poor enough, engineering you can make any material feel harsh or compliant, stiff or flimsy, responsive or sluggish. <S> Ultimately, the best and really only way to determine whether a particular bike will feel good for you is to test ride it. <S> Here is a good video by GCN on carbon vs aluminium frames <A> I'd read this before buying Carbon fibre, the conditions and environmental consequences are huge. <S> See https://polebicycles.com/why-arent-we-going-for-carbon-frames/ <S> Also, if you're doing short commutes, might a cyclocross bike be better, you can fit panniers to some of those which might make it more useful. <A> For a fun rider or daily morning rider/ commuter, considering the price point, I would always consider a good Aluminum alloy frame with good groupset over carbon frame. <S> For very short commutes, like half an hour, take bike that has storage space and makes you work out a bit (for health reasons) <A> I recently started a gig and am commuting 30 minutes each way over patchy city streets. <S> I'm currently riding a steel single-speed. <S> Here are the things I'm looking forward to in my next street bike, once I've saved up for it: <S> Better fit. <S> Track geometry and track handlebars aren't great for me. <S> Better brakes. <S> This bike has long-reach Tektros, which are pretty spongy. <S> More than one gear. <S> Self-explanatory. <S> Pedals suited to street shoes. <S> Track pedals aren't great for this; I plan on getting some MKS "easy superiors". <S> Having a bike that doesn't bounce all over broken pavement would be nice, but that can be achieved in a number of ways. <S> I'm not planning on getting a carbon bike for street riding. <A> There are some things that you need from a good commuter bike: Robustness (so that you don't come late to work too often, and won't need a new frame after an accident) <S> Comfort of posture <S> (so that rides are fun) <S> Efficiency (so that rides are fun and fast) <S> Durability (the bike should live as long as possible with the least servicing as possible) <S> Carbon frames reduce weight, as are aluminum frames supposed to do, so they have a slight efficiency advantage. <S> Let me stress, how slight this advantage is: If you weight 70kg, and your bike weights 10kg, 1kg more for a steel frame would increase your total weight by just 1.25%. <S> However, you don't need to carry that weight, the air in your tires does. <S> The extra weight means a small increase in rolling resistance, but that is dwarfed by the air resistance anyway. <S> I'd estimate that 1kg extra weight will not decrease coasting efficiency by more than 0.5%. <S> The faster you ride, the less efficiency will be lost. <S> So, is such a tiny increase in efficiency really worth the extra dollars? <S> I doubt it. <S> On the other hand, aluminum is more brittle than steel, and carbon fiber is much more brittle than aluminum. <S> With a steel frame, you basically need to ride full speed into a car to destroy your frame. <S> So, this is quite a plus in robustness for steel. <S> In terms of durability, both aluminum and carbon have the plus that they can't rust. <S> However, a good paint job will keep a steel frame from rusting for a very long time. <S> My steel frame has been in heavy use for 15 years, and there's still no rust anywhere. <S> So, carbon gives a negligible efficiency advantage, but that's more than offset by its brittleness and high price tag. <S> Use either steel or aluminum for commuting.
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Upgrading the seatpost, saddle, and tires will make the bike plenty comfortable. Also, for any given price point, an aluminium bike will have better components than a carbon bike, so will probably be more enjoyable to ride. Money can also be spent on more or better clothing - which will make a big difference in comfort if you are riding in unpleasant weather. With a carbon fiber frame, every accident might be the last, a hard knock at the wrong place suffices to break a tube.
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