Does handlebar tape go inside the bar, under the bar-end shifter, when using bar-end shifters? I'm installing bar-end shifters for the first time (Shimano 9-speeds, for what it's worth) and was wondering if I should be running the tape over the bottom of the handlebar with surplus to insert into the bar.  In the past, I've done this and used wine corks or handlebar caps to hold the tape in.  When using cloth tape, this is no problem; foam/cork tape usually is fine too.  But is it the same with bar-end shifters?

Most bar-end shifters require friction between the bar's interior surface to stay put, so no. Install the shifters securely and tape the shifter housing about where you would like it to emerge from the bar tape. You will end up wrapping over the first few inches of shifter housing before it loops forward and may require a bit of futzing to get it looking right.

Here is a lovely video showing shifters being installed on a drop bar.


Help my identify this bike. (3Rensho? Specialized Allez?) Help my identify this bike.
Looks like a 3Rensho or early Specialized Allez but can't find any bikes with same features.
Any info on brand/years, possibly frame size would be welcome.

Not a complete answer, but you can measure the frame size yourself with a measuring tape.

Its not exact, but you'll see to within a centimetre or so.  Road frames normally came in steps of 2cm or half an inch, and sometimes came in 1cm increments for top-end bikes.

Other measurements like top tube length can be measured by starting in the middle of the butting tube.


How do I properly apply chamois cream? There is a lot of advice out there to use chamois cream on long rides to prevent sores and chafing.  How are you supposed to apply it?

In particular I'm curious about the following:

Do you apply the pad or to your nethers?
Do you wipe it on with your hands or a cloth?  What about when you are touring and can't wash up easily after applying?
How much cream do you use?

There's no right/wrong answer.  Just make sure you have some sort of towel available so you can wipe your hands before riding.

What I generally do is place dabs on the chamois and rub the sides together to spread it around -- keeps the hands relatively clean and doesn't require a separate applicator.  Some people prefer to rub it on their butt.

I don't use a lot -- maybe a half ounce (about 15 cc, IIRC).  Others use much more, maybe 2 oz.


Frozen suspension in the winter Winter is coming! Last season I put my road bike in the garage and just rode my mountain bike all winter. Something strange happened: my suspension fork froze. When spring came everything unfroze and was a-ok. Questions:

Should my fork freeze when it is cold outside?
Do you like having suspension when it is below freezing?  I mostly just do road/logging roads.  There are not really any trails where I am.  I don't see too much value to suspension in the winter.  Comments?
If you want to use suspension in the winter do you need a special fork or can you service your fork somehow?

Disclaimer: I used to design and sell after market suspension parts for proflex bikes

There are three main strategies for the "spring" in fork suspension

coil spring
elastomer stack
inert gas, e.g. air or sometimes something fancier.

Nowadays all springs are dampened somehow either by

using oil,
negative air (opposing force on the spring)
friction (frequently used on cheaper elastomer stack forks)

Cold temperatures effect oil and elastomers but have no real affect on the other types of springs and dampers.

In sub 0'C temperatures oil can become much more viscous and can't dampen the shock properly (oil is forced through little holes to slow down the spring-back of the fork) and thus make the fork feel like it is not responding.  If you keep riding, the friction might heat up the oil a bit.

Elastomers are harder to heat up.  I know Proflex riders in the nineties used to pour boiling water on the elastomers before going out for a ride.


Aero bike vs climbing bike for running in Crits I'm considering building a road bike and getting into running Crits this Summer and I'm unsure as to go with an Aero bike or a climbing (lightweight) bike.

Based on my general understanding, when not going up steep hills (which of course is not done in Crits) as a general rule of thumb an Aero bike is definitely faster.

Based on this I would have expected to see most Crit riders on Aero bikes, but when I watch YouTube videos of Crits most of the riders are on lightweight bikes.  There are only 3 reasons I can think of for this:

1) Cost, non-professional riders may already own an endurance bike used for long weekend training rides or commuting on rough roads and not have the $$$ to drop on a 2nd bike just for running occasional Crits.

2) If in the pack most/all of the race, some degree of the Aero benefit would be negated (of course this is not a very good reason b/c if you intend to win then obviously you would not be in the middle of the pack, at least not in the end).

3) Most Crit circuits have frequent turns, perhaps endurance or climbing bikes are better for this purpose?

Even considering the above reasons, the whole point of a Crit is to go absolutely as fast as possible for a relatively short amount of time, therefore I would have expected to see almost all Crit participants on an Aero bike, but from watching Crits on YouTube is seems very few Crit riders use an Aero bike.  Can somebody explain this further?

Revised following clarifying comments

OP is / will be racing in the US
USA Cycling has looser rules for bikes than the UCI, unless the event is qualification for a non-US event.

With these updates, the answer is simply that people rarely race on ideal equipment. Most people I know who race Crits do it either on the same bike they use for road races, Gran Fondos, or other big rides, because they don't have a more suitable bike for the purpose. Those who can afford to drop $5K to $10K on a specialist bike usually don't see Crits as the target: too many crashes, and they tend to see Crits as training rides.

Regarding the bikes you mention, they both appear on a quick glance to meet the USA Cycling Rules 2017. I was initially concerned that the curved top tube was non-compliant, but this guide and the rules already mentioned show that concern to be unfounded for racing in the US. I suspect the FM098 would not meet UCI standards, but that's irrelevant to you.

The earlier version of this answer follows and may be useful for international readers ...

ARTICLE 1.3.011 (and related articles) of the UCI Technical regulations essentially says only a general purpose bike can be used for road racing (criteriums are road races).

I interpret your aero bike to be a time trial bike. The rules explicitly ban such trials bikes from road racing.

The reason for this is the lack of maneuverability.

In practice you'll get much more benefit from sitting on the guy on front.

See UCI CYCLING REGULATIONS PART 1 GENERAL ORGANISATION OF CYCLING AS A SPORT

Especially 1.3.022 and 1.3.023.


Shoe covers (or other tricks) for commuting in shorts I commute to work by bike, very often in casual shorts and waterproof North Face sneakers. Provided I don't want to change my clothes (in particular I don't want to get SPD etc.), is there a good way to keep my feet dry when it's raining?

In particular, would shoe covers be of any help? My impression is that most of the rain gets into my sneakers by streaming down along my ankles/socks, which is why I have doubts if shoes covers would be of any help when I cycle in shorts (but I've never really used them so please correct me if I'm wrong).

In case it's of any importance - if I wear the same clothes and just go for a walk/jog, then my feet stay dry for much longer. Ideal solution would allow my feet to stay dry for a similar amount of time when I cycle.

if I wear the same clothes and just go for a walk/jog, then my feet stay dry for much longer

Do you have mudguards (fenders) on your bike? If not your feet are in the spray from the front wheel and will get wet unless you wear over-boots. Or gumboots.

For cycling when the roads are wet mudguards make a huge different to your comfort. You'll stay dryer because the rain will only hit you from above, rather than spraying up from your wheels as well.

Gary.Ray's answer deals well with the actual shoe cover question. What I would add is that plastic bags and rubber bands work well as a short-term solution for one trip, but they don't last long. But that might help you decide whether shoe covers are worth having at all.


How to change front gearing So I have a bicycle that has a single front gear, but many back gears with a derailleur. I am wondering if I change the size of the front gear (like significantly), meaning if I get a bigger front gear without changing the back gears or derailleur, will the derailleur will still function and not cause the chain to go slack?
If not can I adjust the rear derailleur to a larger front gear?
I am trying to make a generator out my old bicycle, and in order to get a more efficient power output I need to have a higher front gear (since it is an old bike for smaller people so it has a rather small front gear). I am pedaling too fast on it as is right now. I do not know what gearing I have right now.

For a generator you will probably want two sets of gears. Cyclists normally pedal at about 90-110rpm, and getting a small generator to work efficiently normally means spinning at 1000's of rpm. I used a "drill pump" to make a pedal powered pump once and that was designed to spin at 1800rpm. But it used 500W or more at that speed, so I spun it at about 1000rpm using about 200W and that worked fine. Unfortunately I lost interest in taking photos after building the first, single-stage version.

Most of the bicycle generators I've seen use the bike wheel as the second gearing stage, typically having a generator drum 100-300mm in diameter for a ratio between 2 and 6 to 1. The bigger the drum the lower the ratio, but the less tyre deflection so the higher the tyre/drum efficiency.

Depending on what tools you have (mostly, do you have a lathe) you can either use the large cog on the cassette to drive a second cassette, or make an adapter to mount a full size chainring on the cassette. If you get a steel cassette and chainring you can just weld the chainring on, and it will probably not deform too much.

Doing that lets you have a road bike first stage with a maximum ratio of 50T:12T or ~4:1. If the cassette is a wide range one off a mountain bike it could be 12-36, say, giving you a 36:12 second stage or 3:1. That's 12:1 overall, so your 100rpm input becomes 1200rpm output.

You can get the same ratio with a single stage but it will be big and expensive. Assuming a 12T small cog, you will need a 144T chainring to get the same 12:1 ratio. There's one on ebay for $US500. A friend of mine sells large custom chainrings in Australia and could make you a 144T one, but a 90T one costs $AUS200 (about $US150 in April 2016).

I think the important thing is to start with the generator you want to use and work out its ideal spin rate. Then work backwards to the gearing. I suggest leaving at least one derailleur in your final build so that people can vary the gearing a bit to get the most comfortable combination of pedalling speed and load. Varying the generator output has much the same effect if you can do that.


Old Peugeot brakes not working in rain I have an old Peugeot bike that's pretty awesome but the brakes are bad. In good conditions they are weak, and when wet they stop working entirely. I wasn't sure what the issue was with this, and someone had recommended I buy entirely new rims.

Is there any way to make these brakes work in the rain without buying entirely new wheels? I like this bike, but I'm not looking to spend hundreds of dollars to restore it.

Three initial things to do are:

Clean the rims, make sure they are free of anything that is acting as a lubricant. YOu may also consider carefully roughening them slightly with a fine grit sandpaper
Get the best replacement brake pads you can
Make sure the calipers are adjusted correctly and the pads are properly contacting the rim


Speed to power calc on a 'basic' magnetic trainer I'm a dedicated non-MAMIL, and I enjoy riding indoors on a cheap-and-cheerful 14-speed (max tooth ratio 48->14) attached to a $70 basic trainer while watching the footy or listening to music. No wind, no hills, no roundabouts, no car drivers trying to 'door' me, no public shaming from needing to get off the bike to push when I 'gas out' on a hill - seems all upside to me.

My usual exercise protocol is 'steady state' for ~1hour at an average HR in the high-130s and a total cal burn of ~1000kcal, and twice a week I do an HIIT-style workout -

ride until I get my HR to the low 140s (which only takes a few
minutes at cadence ~85 in top gear with 'wine cask' resistance), then
8 x 30-sec maximal effort sprints with 90 sec rest in between.

During my sprints, cadence is 120 (min) to 131 (max) in top gear, and HR always gets to 170 on the second sprint - that's my theoretical max given my age (51) and RHR (58).

After the sprint set, I do another 20-40 minutes at a cadence/gear combination that ensures that my average HR for the entire workout is in the 135-140 range and my average cal burn is 15 kcal/min.

I set my trainer so that it takes a 5-litre cask of wine (which weighs ~5.2kg) to move the pedal from horizontal. (This bit is a key input later, I think).

I'm buying a Wahoo KickR shortly so I will have a fair dinkum speed and power meter and this question will be answered by technology!

Until then I am interested in the performance analytics that can be done with basic mathematics based on what I have now (Wahoo cadence kerjigger in my shoe, Mio Alpha HRM on my wrist, and known-knowns like wheel diameter, crank length, force required to move the pedal, and cog ratio).

By year 10 mathematics it appears that my minimum sprint speed (based on 680mm rear wheel diameter, 120rpm crank cadence and 48:14 ratio) sustainable for 30sec is ~51km/hr, with a peak of ~56km/hr (at 130rpm, only held for seconds - so not relevant).

Those seem inordinately high for a fat old indoor hack - but bear in mind there is no wind resistance, no drag, and to the extent that the 'wine cask' resistance mimics a slope I'm not actually having to move my bodyweight (104kg) or bike (12kg) up the slope.

So here's the question (finally): is there enough information there to estimate power?

We have:

crank length 175mm;
rear wheel diameter 680mm;
cadence 120 rpm;
gear ratio 48:14;
mass required to move pedal from horizontal 5.2kg (with empty bike)

I am reasonably certain that my (and the bike's) weight - 104kg and 12 kg respectively - are irrelevant, except to the extent that when I get on the bike the mass required to move the pedal would increase slightly (probably not enough to really make a meaningful difference to the calcs).

Almost all the power formulae that I've found, use the rider+bike weight - which is pointless on a trainer. If I subtract my weight, then the power formulae return garbage (and are way out of whack with the caloric expenditure during the 'effort' sets).

Has anybody got any insight on this?

The short answer to your question is: no, there's not enough information.

In the main, the information you lack is about your particular trainer's resistance curve as it varies with roller speed. Each magnetic trainer has a particular "design curve" for its resistance, and you can see some examples here. As you can see, magnetically-braked trainers tend to have a "flatter" power curve than fluid or turbofan trainers. Different manufacturers will use different numbers of magnets and different thicknesses and materials for their rotor in their resistance units. Some magnetic units allow you to alter the distance to vary the resistance. And, each load generator typically has a way to dissipate heat so the load often varies even for the same roller speed when the unit is cool vs. warm. You can often see this by directing a fan at the load generator and noticing a change in resistance. In addition, as parts wear over time the load units and bearings can become misaligned.

You are (almost surely) correct that your total mass (you + bike) is irrelevant since for (almost) all basic magnetic trainers, the roller-to-tire contact is set by turning a knob to press one against the other. That roller-to-tire contact is the same whether you are on the bike or not. When you ride on the road, on the other hand, the road-to-tire contact is determined by your mass. As an aside, trainer rollers are typically about 3 to 4 inches in diameter so for a given total mass the roller deforms the tire more than it would on a regular road surface, so a Newton of force on a trainer roller imposes more rolling resistance than the same Newton of force on a road.

BTW, here is a way to check your "cask on pedal" method for calibrating rolling resistance: Adjust the tire-to-roller contact so that your 5.2kg weight just begins to move the rear tire in a 48-14 gear ratio, as you've been doing. Then, vary the gear ratio and find the pedal weight that will once again move the rear wheel. The ratio of mass to gear ratio ought to be constant.


Why are almost all bicycle tyres cross-ply/bias ply and not radial construction? Most times when I see a failed bicycle tyre (one where the threads are showing through) they look something like this, with diagonal threads clearly visible

Here's a random manufacturer's cutaway showing diagonal casing threads

Here's a line diagram showing the difference:

So I'd reason that most/all bicycle tires are Cross Ply in build, and not Radial.

My google-fu does return these points:

Radial tyres are cheaper to make than the equivalent cross ply
Radial tyres are lighter and have better fuel economy than a cross ply
Radial tyres track better, where cross ply tyres have been known to "tramline" vehicles.
Cross ply tyres have a more rigid sidewall, radial tyres have a more supple sidewall.
Suspension needs to be altered in a car to accommodate the differences between ride handling in the two styles.

Usage

Automobiles tyres are almost exclusively radial.
4WD tyres are predominantly radial, but cross ply have much better sidewall strength and resist damage better.
Motorcycle tyres may be either, where radials are preferred for speed and cross ply are preferred for load carrying (touring or cruising)
Truck (ie load carrying vehicles) might use either, with cross ply for load carrying and radial for long distance.

Even wikipedia is ambiguous, saying

  Radial tires have occasionally found application on bicycles, used on the 1980s Miyata touring bicycle; models 1000 and 610,[19] and more recently in 2009 on the Maxxis Radiale.[20] Panaracer radial tires were also standard on the Jamis Gentry model bicycle in 1985.

I would have expected that radial construction with "supple side walls" to help a lot in reducing rolling resistance, but its uncommon.

Why are Radial tyre constructions uncommon in bicycle tyres?

Radial bicycle tires are very rare. The reason is that the lateral stiffness is much lower than for cross-ply tires. Imagine that you press the sidewall of a tire by your thumb. With a cross-ply casing the cords on which you apply pressure are anchored to the bead wires over a distance of about twice the tire width and the whole section shares resistance to deformation. In case of a radial tire the cords run in the same direction as the force, hence offer very limited resistance. Radial tires are prone to squirming and unstable cornering.

Yet a few manufactures still offer radial tires. I know of the Vittoria Diamante Pro Radiale 700x22 for road bikes and the CST Sensamo Speed 35-622 for touring bikes.
The riding experience with the Vittoria tires, published on https://cycletechreview.com/2012/reviews/vittoria-diamante-pro-radiale-tyre-review/  , suggest that they might please persevering afficionado's.
It is probably not accidental that the width is limited to 22 mm. The bigger the diameter, the softer the structure get and, probably, the higher the inflation pressure required for stable load carrying (limited load carrying might be the explanation why airplanes and heavy trucks don't use radial tires but cross-ply tires).

In his study of tire properties, Andrew Dressel included a Maxxis prototype 22-622 tire. He reports (page 113)  'The Maxxis prototype, which is described as “radial” and does appear to have cords aligned at about 22.5º, instead of the 45º usually associated with bias-ply, does not have stiffnesses noticeably different from other tires of similar size.' Here the small width combined with the in-between design would explain the results. See  https://dc.uwm.edu/etd/386/


Intrepid twenty on speed, getting information and understanding the gears? I have just started using my bike casually for exercise and wanted to know the Gears, Front gears 1-3- Back gears 1-7, When do i switch from downhill to uphill?
I was told to keep on 3 Front ad back gear from 2-3 depending up or down hill, and getting the speed i need, not to over work my legs?

okey so if you have to keep the chain preaty straight to keep the chain live healy.So  from what i was told, if you ride with the smalest gear on the front on the back you have to use the bigest the second bigers and the tird biges. if you use the midle gear on the front on the back you can use the 4th bigest,5th bigest. and if you tide on the front the bigest gear you can use the 6th bigest and the last one with in you case is 7th (that was what i was told if its wrong im sorry).


Best bike routes in Brooklyn I live in Brooklyn, NY and in order to get in a decent 30+ mile ride (road bike) I either need to do 9 loops of Prospect Park (ugh..) or head into Manhattan, go up to the GWB, and onto 9W. Then I need to come back. Getting to the GWB is a real pain from Brooklyn and not reasonable time-wise weekday mornings before work, since it takes over an hour just to get out of the city.

Question: Do you guys know of any 30+ mile rides that are unimpeded by pedestrian or car traffic starting around Prospect Park? Happy to head to East New York or Queens.

Thanks.

There are essentially no rides that are 'unimpeded by pedestrian or car traffic' around Brooklyn, because Brooklyn is on a densely-populated island adjacent to another even more densely populated island so there's no nearby countryside, and we still use our rail lines very heavily so there are no rail trails.

The 30-miler I've found with the most 'open road' feeling is heading to Breezy Point on side streets through Flatbush— take something like E. 35th Street down to Marine Park, then take the bike trail along Flatbush Ave. to the Marine Parkway bridge and Rockaway Point Boulevard. There are very few lights between the Flatbush Ave. bike trail and the tip of Breezy Point, so about half of the ride is unimpeded.

I usually loop back via the Belt Parkway bike trail and take Bedford Avenue back north.

Basically, something like this:
https://www.google.com/maps/dir/Prospect+Park,+Brooklyn,+NY/Beach+227th+St,+Breezy+Point,+NY+11697/@40.6275278,-73.9439275,13z/data=!4m34!4m33!1m25!1m1!1s0x89c25b1087680443:0x178bf7c600df7a98!2m2!1d-73.968956!2d40.660204!3m4!1m2!1d-73.9620066!2d40.6631979!3s0x89c25b0d7ded003b:0xc1bbc03310eefdd0!3m4!1m2!1d-73.9476347!2d40.6597135!3s0x89c25b655fbe3f19:0x2445bed892551a5c!3m4!1m2!1d-73.9438733!2d40.6425748!3s0x89c25b5a445c57a3:0xa1b0241726698868!3m4!1m2!1d-73.9313515!2d40.6063921!3s0x89c2436130911e41:0x34bf5c3bfeec3860!1m5!1m1!1s0x89c243fe55767105:0x64ffd3f4302f0ba6!2m2!1d-73.9328573!2d40.5524677!3e1

But if you want easy access to 'real' road riding from the city, you'll probably want to live in Northern Manhattan or the Bronx.


Buying a bike: Older, used high-quality components or new average-quality components? I realize that fit and personal comfort, etc. are most important, but, I need some advice.
I just got into duathlons and triathlons this year, and started with a very low end bike. I'm now looking to upgrade, but not trying to go crazy.

My question is regarding good versus average components. Are older great components better than new average components?
For an average rider, with some racing goals, etc, does new outweigh better, or does quality always outweigh age?

None of the items are bad, just older or better.

I'm specifically comparing a used 2007 bike with a Shimano 105 groupset and a 2016 bike with a Tiagra groupset.

Trying to remain general - and assuming both bikes are a good fit for you, I'd base the decision on Warranty.

The older bike is a decade out of date and will have a decade of use on it... but that could be anything from 0 km up to 50,000 km of travel.  So it should be in the "couple of hundred dollars" range at most.

The new bike will have a store warranty.  If you feel you will need that support, then a new bike is a reasonable idea.  But the new bike will cost you five to ten times as much as the used bike.


Abus Folding Lock: Adding Damping to Joints I want to add damping to the joints on an Abus Folding Lock, such that it maintains its shape if I stick it through a hole or something.

I received some brief feedback that I could use rubber bands or O-rings; however, I'm not familiar with what might work best, which options of that component are available (and might work best), or how to implement.

Would anyone have any suggestions?

Background:

I began this question here, posted below. The people on bikeforums said it sounded like a DIY project, and thus I came to stackexchange thinking there would be a DIY community  who could further advise me on how to approach this.

Instead, I only found Home Improvement (DIY for houses) and Motor Vehicle Maintenance and Repair (DIY for motor vehicles), so the question has been placed to Bicycles, where people seem to be familiar with the Abus Folding Lock.

Please inform me if there is a better board.

Original Post:

I read about the Abus folding lock here, and then researched it in other places.

I since purchased it, and developed opinions about it. I sent feedback to the company, but wondered if I was alone in thinking that this feature would be a good idea:

  [Feature Request]: Damping in the Links

  I recently purchased an Abus folding lock for use with my bike. I like
  the extra versatility it has over traditional U-locks

  Since my purchase, I have found several situations in which a U-lock
  can more easily wrap around an object.

  When a U-lock is passed through an object which the user's hand cannot
  also pass, (such as a mesh wire fence) its shape allows it to wrap
  around an anchor (such as the wire mesh fence post)   and easily
  return to the user.

  A folding lock passes through these objects easily, but loses its form
  in areas where the user is unable to reach.

  Have you considered placing a weak dampers in the links, such that
  users could form your lock into shapes and weakly maintain those
  shapes while they are setting up the lock?

I use an ABUS everyday. Keep the lock orientated on its side, the friction in the joints will help it keep its form.  The friction is essentially the dampening units you interested in.  If you maintain this orientation you can set a shape and carefully pass it around something.  The moment you change the orientation, to something more vertical, the friction in the joints will lessen and the lock will take the lowest energy form (typically straight down, hitting you in the shin or chipping the paint on your frame - hrrmm...).

I am sure ABUS could add nylon washers to act as explicit dampers, furthering this friction effect, but this would likely increase the cost (for an already expensive lock) and could wear overtime adding slop to the joints.  Slop could be bad as it could make it easier for theives to insert wedges to try and attack the joints (arguably the weakest point of the lock).


For what kind of bike and under what riding conditions would a Biologic FreeDrive Chain Cover be suitable? I've got a Strida 5.2 and absolutely love the greaseless experience.

For ordinary chain bikes, when could a Biologic FreeDrive Chain Cover be used without causing troubles, but only provide a cleaner ride?

I'd say "when there's no rain, mud or grit on your route". That thing looks as though it's designed to collect any loose material that falls into the open lower section and make sure it stays on your chain forever.

Recumbents commonly use sections of poly pipe (cheap black flexible plastic pipe) to cover their very long exposed sections of chain, and that works fairly well. You could do the same on the shorter chain of an upright and get most of the benefit of the solution above without the penalty. Easier with a singlespeed or hub geared bike, but possible with derailleurs (the attachments need to be flexible).


Why rear derailer has limit on front chainring difference? Just as an example, Shimano RD-M786-SGS (as most other RDs) specification says "Max. front difference: 22T".
Why is rear derailler limited in front max difference? It is clear that it is limited in total tooth capacity, but max front difference is stated separately. What goes wrong if it is exceeded, given that other numbers remain within their specified limits?

It is not directly connected to the difference between the front chainrings.
Instead, a Rear Derailleur will have a "capacity" which is the total amount of chain it can take up before bottoming out.
The RD also has a value for the small cog (often 11 tooth) and either a maximum-sized cog, or some of the new specs give a maximum and a minimum tooth count for the big cog.
For example, that specs page linked in your question says

Low sprocket_Max. 36T
Low sprocket_Min. 32T
Top sprocket_Max and Min. 11T
Total capacity    43T
Max. front difference 22T

The cassette can "eat up" between 21 and 25 links, and the total capacity of the RD is 43T.
43T less the 21T consumed by the smallest allowed big-cog is 22 T
So your bike might have a 48T big chainring, and the smallest chainring is 26T.  Any middle chainring has to be between those.
You could have a 53 tooth big chainring, but your smallest could be no smaller than 31 tooth.
summary  The chainring difference is easier to understand for consumers, its just processed the other values.

Putting this another way: Imagine your hardest gear is 48:11 and easiest gearing is 26:32.  The rear mech will be almost flat, pointing forward and the chain through will be near straight.
Changing chainrings releases ~22 links of chain, which adds to slack.  Your rear mech has to fold up and take up ~22 links, now its in 26:11.
Then changing up the cassette uses 32-11 = 21 links of chain.  Thats the lower boundry.  If you had a 36T max on the rear, it would use up 36-11 = 25 links of chain.  Those two values of 21 and 25 straddle the 22 tooth number quoted in the spec.
Note that Shimano's specs are notoriously conservative too, you can almost always add 2 teeth to any maximum and still have perfectly good performance.

If you had far more difference between your chainrings than 22T, it wouldn't shift very well.  16T is quoted as a reasonable maximum between adjacent chainrings, and 22T would imply a triple crankset with a third chainring.
So if you exceeded the front difference of 22T with (say) 30T, then moving from big chainring to small would release ~30 links of chain, the extra 8 links has to go somewhere.  This might let the derailleur rub the chain back on itself in a small-small gearing, or would not put enough tension on the chain resulting in sloppyness and possibly chain slip.
Example: This chain is too long, and is rubbing on itself.  The gear is a small:small combo so there is the most "spare" chain outside of the chainrings/cassette.
  From Is my chain too long?


What era is this JC Higgins 24" bike? This bike has no serial number, I've looked it over thoroughly. Nothing on the bottom bracket, nothing on the dropouts. I don't expect to find out the exact year but seems there should be a way to narrow it down based on the components. I haven't been able to find many JC's with this particular fork (rounded top as opposed to the flat top). I haven't yet found information on what years skip chains were used but this bike has one.

1949 - 1950 JC Higgins built by Murray.  The serial number is stamped into the bottom bracket.  Time and rust will make it difficult to read.  Keep scrubbing.  MOS is the prefix for Murray of Ohio for Sears.  L, M, N, O, P will indicate the year.

This bike is missing the tank.

Here's a picture of one complete with tank and rear rack. Some models had painted tanks rather than the exhaust ports. Some had painted rims, some had chrome rims


Can I get a wheel dished without the bike? I broke a spoke on my rear wheel, and ended up messing with it a bit too much - I may need to get it re-dished.

If it's a common market model bike, can I simply take the wheel into my bike shop, instead of the whole bike? Will it work when I bring it back home?

The problem is I can't ride it in because the disc brake is scraping on the caliper.

Yes, a dished wheel can be built or re-dished without a frame handy.

In order to get the wheel to revolve, the rim must be equidistant between the insides of the stays/fork. The reason why most rear wheels/front wheels with disk brakes are dished is because the hub flanges aren't centered between the ends of the axle. This is to accommodate the width of a cassette on a rear wheel and the space taken up by a disk on a front wheel.

To accomplish the desired dish, a mechanic will lace a hub to a rim using spokes that will result in the correct rim placement. There are all sorts of calculators out there to correct for the offset from the hub flange. The spokes on opposite sides of the wheel will be at different tensions and lengths, as opposed to a dishless wheel which has spokes at the same tension and length on both sides. People commonly break spokes on the drive side of their rear wheel - this is because those spokes are generally at a higher tension than those opposite it. Ideally, a wheel is dishless so as to evenly distribute the stress on all spokes. To achieve this, there are many offset rims which compensate for some of the hub flange offset.

However, none of that will effect the disc or caliper function unless you've misplaced some shims reinstalling the disk or moved the caliper. If you have hydraulic brakes and pulled the brake lever without the wheel installed, the brake pads will probably just need to be pushed back into the caliper housing with something flat and blunt.


Why aren't sportive' 'bikes popular outside the UK? I recently bought a 'sportive' bike, i.e. very much like a road bike but with a taller head tube to give a slightly more upright, more relaxed, less 'heads-down' riding position, and a triple chainset rather than a compact double.

I think this is a great bike (I'm not telling you its make or model as I don't want to discuss the pros and cons of this specific bike), but the US-based manufacturer produced it in 2010 only. I happened to meet a UK-based employee of theirs at the weekend who told me although this bike was designed specifically for the UK market, its (worldwide) sales turned out to be too small to justify continued production. This surprises me, as I have the impression that only a small proportion of the (lower-end) road bikes sold are ever used for road racing or time trialling, with more used for fitness and day rides, including the sportive events that give this style its name, and that this style of bike is ideally suited to such uses.

Can anyone explain why such bikes aren't popular outside the UK?

That site's basic definition of sportive boils down to:

more upright riding position
more comfortable for distance riding
longer chainstays, taller head tube
softer forks (though many brands have gone to carbon forks across the board)
yet still with drop handlebars and quality components

And I think nearly every brand in the US has entries in that realm, though they often call them things like "endurance / sport / performance" as compared to "race / competition". Basically it comes down to "comfort geometry not race geometry"; components, materials, and even gearing choices are often similar or identical.   Of course their race models often extend up into exotic carbon frames and top-end component groups, where sport models may only go up to basic carbon frames and mid-level groupos.

Some examples (aluminum frames):

Brand          sport geometry     race geometry
-----          --------------     -------------
Cannondale     Synapse            CAAD 10
Felt           Z series           F series
Giant          Defy               TCR
Specialized    Secteur            Allez
Trek           ?                  2 series

These are all drop-bar road bikes, but the first column has a little more forgiving ride for long distances, while the last column has racier / faster handling.  But both kinds are raceable if you want (they're not all that far apart).  Both can usually be had with your choice of triple or compact double crank gears; a standard double seems more available in race models.

So 'sportive' bikes are available in the US, just by different names.


Shoulder pain caused by messenger bag? I have a professional messenger bag (chrome mini metro messenger) I have been carrying for about 2 months. The bag weighs around 3 lbs and I generally carry about 4 lbs of stuff in it. Biketools, phone charger, gloves etc. Its less than 8 lbs and I still get shoulder pain.

I am 190lbs and 5'10

Am wondering if there is something I am doing wrong - I see a lot of messengers in the city with huge bags and always wonder if they have shoulder pain from carrying bags on one side for years.

Below the actual bag although i have it higher up without using the side strap.

Take a look at your riding position.  When I was much younger (about 10-12 years ago) I used a messenger pack all the time while in an aggressive riding position (e.g., track bike / road bike) . In that position I found your lower back supports most the weight of the bag.  In a more upright position it pulls on your shoulder more.  As a test, try walking around for a while with one... it sucks.

If you prefer a more upright riding position (no judgement!) then a messenger bag may simply not be the right fit -- sorry pun intended, my bad.


What is a kermesse race? I heard about a local club holding a kermesse race, and I was wondering what exactly they were?

Not a big fan of this type of answer, but wikipedia has a pretty good definition of it.

  The races are usually 90-140
  kilometers in total length. While some
  are longer or shorter, most are about
  120 kilometers. The race is comprised
  of a set distance and number of laps
  over the established course[2]. There
  are typically 10 to 20 laps, of
  between 5 and 10 kilometers. The race
  usually begins and ends in the center
  of the town which is hosting the day's
  race. The race will occupy the roads
  in town as well as the roads
  surrounding, either city streets or
  farmland.

  The course usually has a rolling
  enclosure. This means that while the
  race is not passing through, the
  streets are open to traffic. A
  designated car, usually with a caution
  sign and a red flag, leads the riders
  and close the cross streets to
  traffic. A following car, usually with
  signs and a green flag, open the
  streets back up to traffic.

  [...]

  The kermesse is similar to the
  criterium but differs primarily in
  total course length and lap length.
  While a criterium traditionally last
  60-90 minutes, a kermesse will often
  take 120-180 minutes. A single lap in
  a criterium is usually less than 5
  kilometers while the kermesse is
  usually 5-10 kilometers per lap.

See the link for info on payouts and UCI information.


Ebike throttle not working Hi members friend got a dohiker ebike off ebay got it went for a ride came home and everything was fine...
plugged it in to charge and then just stopped working pedal assist works and walking mode works but when to turn the throttle nothing won't work ..
I had a friend come look at it tonight he bypassed the throttle an nothing ..  its very strange

Id check out all the connections firstlt then id check for any breaks in the wiring as with it being a foldup bike ive heard of the wiring being caught/streched when folding down etc it could be a simple cause as this if not it almost definitley looks like a failing on the throttle mechanism to me


Fixing pinches with latex-based sealant? Having had yet another botched transition from a kerb to the road (and possibly some underinflation) I’ve heard that horrifying thump as the weight of the steel rims and the lock crashed down. Sure enough, I woke up to a flat.
Thinking it is just the pinch from the kerb and nothing else, how are my chances of fixing it just by pouring some DocBlue in?
It’s a hub, so changing the tube is something I’d ratger avoid for now if I can

Latex based sealants are great at fixing the sort of small holes that you'll get from thorns and glass. If the hole is too big, then all of the sealant will just rush out with the air in your tube. Pinch flats tend to make a big enough gash in the tube that sealant is useless.

People will often talk about using sealant to avoid pinch flats because they're talking about an entirely tubeless system. This means that the sealant replaces the tube altogether, leaving nothing to pinch at all. Unfortunately this can't just be done on any setup with any old tyre, making it an expensive venture if your wheels and tyres aren't already tubeless ready.

Once you've fixed the flat, the best solution (without spending $$$) to avoid pinch flats is just to run higher pressure in your tubes.


Need opinion on upgrading groupset for my road bike I just moved to UK for my masters and was looking for a road bike. I found a pretty old ribble 631 road bike taht was barely used. Its supposed to be around 20 years old but still has decals intact. The seller said that the bike was too large for him so he just used it on a turbo trainer. I paid £560 for it.
Rear derailleur - Shimano 105
Front derailleur - Shimano 600ex brand on
Brakes - Shimano 105
Brake levers - Shimano 105
Gear levers - Shimano index RX400
Rear cassette - shimano 12 - 24 ( 7 speed )
Wheels - Mavic MA3 rims on Shimano 105 hubs
Headset - Shimano 105
Stem - SR quill
Bars - Richey Pro T6
Seat post - Titanium with alloy layback clamp
Seat - San Marco Ponza
Tyres - Michelin axial sport
frame - ribble 631 reynolds road.

Although the bike is in pretty pristine condition, I am not used to downtube shifters.
The shifters are downtube, the front is friction, the rear is indexed. . I am thinking, I'd upgrade parts of the groupset, to a 10 speed cassette, bar end shifters and rear derailleur. The cost comes to another £250 if I source the items as cheaply as possible.
Here are my concerns -

Did I overpay for the bicycle ? I do have a feeling that I did :(
Should I spend the extra on the upgrades?

That's a nice enough bike, but it's not something to upgrade, you bought the wrong bike. Either you want a vintage bike in which case it sounds great, or you just want a road bike, in which case something with Shimano Claris R2000 would be suitable.
Assuming you have 400EX, then this dates from 1990-1992. 600EX would be pre 1988, so it's possible you actually have Exage Sport, which is more contemporary with 600EX.
631 tubing however suggests more 1990s than 1980s
I would suggest a value maybe £200? https://www.facebook.com/Retrobicyclesrecycle/posts/3754668234607817
There is nothing special about those components, though they aren't bad.
I had a look on fleabay and you could buy a generic modern(ish) bike such as a Triban 540 with 2x10 speed 105 and carbon fork for about £300. Or you could buy a new 2 x 8 speed bike such as the RC 120 for £400.
Not much to do with it except buy some new tyres if they've perished. Sell it if you don't like it. Buy a more suitable bike.


Freezing headset cups to ease installation - does this actually work? Sometimes it can be a tight fit installing a headset cup / race. Bike forums are full of people saying putting the cup in the freezer helps installation based on their anecdotal, uncontrolled experiments. Internet forums are also full of people saying it doesn't help at all, or you need to use dry ice or something else.

Aside from everyone's personal anecdotes, or what someone on the internet said one time, is there any evidence that freezing headset cups makes them easier to install? Does freezing them really shrink them sufficiently to make a difference?

According to this link the thermal expansion of aluminum 6061 is 13 micro inches/(inch x °F).  A headset has a diameter of 1.125 inches, and circumference of 3.5325 inches.  Assuming you change the temperature of the headset from 70°F (room temperature) to 0°F (typical household freezer), you'll change the circumference by 13 x 70 x 3.5325 = 3215.5 micro inches.  Which is .0032 inches. The diameter will now be smaller by .001 inches.  I really don't think that will be enough to make a difference when installing a headset.  Hopefully somebody can check my math/science to ensure I'm applying the information correctly.

Here's a nice chart illustrating the thermal expansion of aluminum from 0 K to 293 K (20°C).  This seems to fit with my numbers from above that shows a decrease of 40 degrees (+20°C to -20°c) results in a change in length somewhere in the vicinity of 1x10-3 length units.


How to remove completely stuck saddle post from frame I am helping a friend fix his bike that he got for free. Everything went well, except that I cant raise the saddle. The seatpost is really stuck in the frame.

The clamp was easily removed. When I tried to turn the saddle only the saddle itself is turning, and the seatpost remained stuck. I tightened the saddle bracket as hard as I could, and I managed to turn the seat post a few millimeters back and forth. But somehow it is even more stuck now and I can't move it at all. I am afraid that I will bend/break the bracket in the seat if I tighten it anymore.

I tried with a pipe wrench and still couldn't twist it. Perhaps I will be able to if I have another person holding the bike so I have two hands for the wrench. I did manage to damage the surface of the seat post though.

I have a few questions:

How would a professional remove the seatpost?
Why is it even stuck? Can this happen because of rust, or is it more likely because the previous owner hammered a 30.2mm seatpost into a frame meant for 30mm? I can see at the Wikipediaartikel (link) that both 29.6, 29.8, 30.0, 30.2 and 30.4mm are common sizes. As I don't have a precise caliper I can only tell you that it is approximately 30mm.
If it is because of rust, can I polish off the rust and use the same seatpost again? If so, should I polish the post or the internal part of the frame?

Penetrating oil (Liquid Wrench).
It may take a few days as it needs to work its way down.
Or it may free it up in a few minutes.

The risk you take with a lot of force with a pipe wrench is you bend the bike or brake off the post or get the post out of round.

You should grease the seatpost to help prevent this.  If you don't bend the post then I would reuse it.

It is most likely rust.  You cannot hammer in an over sized seatpost.

If you do sacrifice the seatpost and use a use a lot of force with a pipe wrench then don't have the pipe wrench close to the bike as you could get the post out of round and really jam it in there.  That may have happened when you got it to move a bit and then jammed.

You have a couple comments of use heat and I don't disagree but I would hit it with penetrating oil for a couple days before I resorted to heat.  Not just once.  You need to hit every few hours with oil.  If you do go heat then heat gun before torch.


Rear disc brake question I have a dynacraft next mountain ridge 26" bike & it already has a front disc brake but would I be able to add a disc brake to my rear wheel which previously had a v brake on it that I ripped off?

To add a rear disc brake you must have a frame with a disc mount. You will also need a rear wheel that has a disc compatible hub. Unless you find a really good deal on something used you will spend more than the bike is worth. If you feel the rear V brakes were insufficient, your money would be better spent getting quality shoes for the rear. Some riders claim good quality V shoes work as well as low end discs.


Will Shimano 105 FC-R7000 replace R565 I have a 2013 Trek Madone 4.5 with 10-speed Ultegra groupset, current crankset is a Shimano R565 50/36 compact. I want to replace the worn out crankset with a new lighter and up to date crankset. Will the new Shimano 105 FC-R7000 11 speed crankset work on this bike?

Should be a drop-in replacement.

Presumably you have a Hollowtech external bearing bottom bracket in a 68mm shell. Latest generation Shimano cranks all have 25mm axles that fit in Hollowtech BBs.

11 speed crank will work with a 10 speed chain.


Hybrid/gravel bike mudguards/fenders with specific coverage Are there any aftermarket fenders that only span from the chainstay to the seatstay? I don't trust the rigidity of full-length mudguards beyond the chainstay and this is only to minimize contamination towards my front derailleur. I would prefer it if there's no cutting/bodging involved.

Not a great answer, but I did something like this on my old MTB.

This isn't a good photo because the mudguard broke (for other reasons) and when I repaired it, the linkages no longer move the same way.

However you can see that the original seatpost clamp was used around the seat tube (in yellow)

At the bottom, the tip is wedged into the triangle space formed by the kickstand bracket and the two chainstays.  It is not going anywhere.

On the plus side, these mudguards are cheap and common.  But they tend to get brittle and snap.

There's plenty of clearance, its a bit harder to see in the first photo so here's a downward shot.

Why did I do this?  Back then I had a rear parcel rack fitted, which was lined with a sheet of stiff plastic that extended backward quite a distance.  The only part not covered was where the canti brakes are, and the rack was lower enough so this wasn't a problem.


How long for legs to get used to fixed gear 15 mile daily ride Due to a car accident and the extended time insurance has taken to get my car handled, I pulled my fixie out of the garage and started riding it to my university mon-fri; it's about a 15 mile round trip, no hills. I have been doin this ride for 3 weeks now and my legs are still significantly sore from the ride every day. When I am riding, there are no issues with my legs or stamina or anything, but lets say I am standing and I keep my leg straight and try to lift it; at about 45 degrees the top part of my leg where it meets the hip/pelvis there is pain and I cant really lift it any higher. Is there a certain point where after having done this ride 5 days a week for a given number of weeks that I will not have this issue anymore? If anyone knows any stretches for cycling too that they would like to suggest, that would be appreciated too.

For profiling on this issue I am 5'5", 120lbs, and have been significantly inactive for the past year as a university student (literally spend the large majority of my time sitting in a chair).

First off, I assume when you say "fixie" it is a pure fixed-gear bike? It's not a flip-flop (where the wheel can accommodate a fixed cog on one side and a freewheel on the other)?

If it is a flip-flop, you'll find it easier to ride single speed rather than fixed.

Second, I agree with much of what @Arne has said in your comments. From these you say you're riding 45x15 - I think one of the beauties of fixies is that they're easy to work on, and you can easily buy cogs with more than 15 teeth. Similarly, but a bit more expensive, you can easily buy a chainring with fewer than 45 teeth. Either of these (or both of them) will make your ride easier (and therefore ease on your muscles).

A site I like is Velosolo, not so much because they have great prices or anything (although I have bought from them and it was a good experience), but they have a good selection of single-speed/fixed-gear parts, so you can evaluate what your options are.

But make sure you keep your current parts as you'll likely want to put them back on the bike in a month or so.


How to remove old kickstand I'm trying to cannibalize an old bike but am having trouble removing the kickstand:

I've tried screwing the bolt counter-clockwise†, which indeed made it looser, but it's not getting loose enough to remove the kickstand; What might I be doing wrong here?-- is there possibly something worn/rusted out which is causing the bolt to not loosen any further?

† At least I think I turned it counter-clockwise, but I may be remembering wrong. Could it actually loosen by turning it clockwise instead?

Just keep unscrewing (it's a standard thread) until it comes completely loose.  Typically the bolt for that style of kickstand is incredibly long, so you have to unscrew for a long time.


Are saddles supposed to bow inwards when sat upon? One common theme I've noticed among saddles is that when I sit on them, they bow inwards at the middle where there's no support from the rails.

In order to compensate for this, I find myself tilting my saddle back a bit farther than I'd like it to be, so that my weight stays on the sit-bones. If I don't tilt the saddle back, I end up sliding forwards.

I once had a really horrible BSO saddle that suffered heavily from this effect. When I sat on it, it basically became a banana. I ended up jamming a block of wood between the rails and the bottom of the seat, and it fixed the issue. I've since upgraded to a better saddle (Velo), but it still does a bit of this.

Is this supposed to happen?

Edit:

I ended up solving this buy moving my saddle back. It kept me from sliding forwards and allowed me to nose the saddle down to level.

Yes, this is how saddles work. If you find yourself sitting on the rear edge of the saddle and sliding forward, you probably need a seatpost with more offset.

You might also be interested in SDG I-beam design. It has been around for more than 10 years and while not unpopular enough to be out of production, it also hasn't replaced the traditional rails design.


Recessed brake pivot nut stuck in carbon fork The recessed pivot nut for my front brake calliper (no. 4 in this diagram) has seized inside the fork.

I've managed to remove the brake calliper itself by unscrewing it from the front, but the nut is stuck so tightly that I'm worried I'll round off the socket if I try to extract it with a hex key.  I've tried dousing the assembly in GT-85 but it doesn't seem to be helping.

Someone suggested screwing an M6 bolt in from the front and knocking it through with a hammer, but I'm not sure how hard I can safely hit it (my careful attempts so far haven't worked).

Am I likely to damage a carbon fork by doing this?

Please don't hammer it from the front. You risk rotating the nut and completely jamming it in the carbon.

Keep at it for a few days with penetrating oil. If that doesn't help:

Try to remove the nut by pulling it out from the rear.
I would suggest finding out what size bolt will fit through the entire nut (perhaps M4). Get a long bolt or piece of threaded rod in this size and slide it through the stuck nut. On the front side, thread on two nuts and a washer (the washer goes between the nuts and the stuck nut).Screw both nuts tightly together.

On the rear side, place a small plate of (ply)wood with a 5mm hole in it. Make sure the block is shaped such that it comfortably rests on the rear of the fork legs/fork crown. Take some time to shape the wood, depending on your fork geometry to avoid any damage.

Thread a washer and nut onto the wood block, and thread on two nuts at the end of the rod again.
Use a wrench to hold the the nut on the wood block, and another wrench to move the two rear nuts to pull out the whole assembly, including your stuck nut.


Which way should a seat post clamp be oriented? I heard somewhere (I don't remember where) once that a seat post clamp should be oriented with the gap at the front of the seat tube, opposite of the gap in the top of the seat tube. The logic behind this was that it supposedly exerts more equal pressure around the entire seatpost.

However, I've noticed that bikes off the rack are almost always sold the other way around, with the two gaps on top of each other.

Does it really matter? Is one way better than the other?

Typically, for an aluminum post you align the gaps. For a carbon post you turn the clamp 180 degrees from the gap in the seattube to minimize the chance of crimping the seatpost. Some manufacturers have their own recommendations, but they're typically in line with what the aforementioned guidelines.


Suggestions for buying a bike for commuting I've decided what kind of bike I want (light hybrid with straight handlebars),
but have no idea how to chose a brand/model.

What questions do I ask at the shop?
Which brands are good?
Am I paying too much for brand-value?
Am I paying for things I don't need? (Carbon Fiber fork...)

What are the things I should look out for in particular?

Another thing I find difficult is that they don't let you try out the bike except  in the shop (and without the pedals attatched).

Check out:

For a long (25mile each way) commute, what kind of bike should I look at?

What bike+equipment for a long daily urban commute?

How do I change a road bike into a commuter bike?

Relative efficiency of different commute bike setups

Equipping a commuter bike

What is the narrowest tire you would use for commuting?

(And others)


DT swiss 370 hub ends in a thread, what is is for? I bought a second hand wheel which has a DT Swiss 370 hub. I miss-thought the hub is for a 135x9 mm axle, but it is not. After finding out that it was not a 9 mm I took a deeper look to the hub and found something that surprised me, the hub ends in a male thread.

I was not able to find the user manual... So my questions are:

Does this hub need a 135x10 axle?
What is that male thread for (see images)?, is it supposed to rest on the frame directly?

Outside of the hub, the DT 370 rear axle looks like this:

135x10, 135x10 QR, or just 135 QR, would all be accurate ways of describing the axle standard as far as frame compatibility is concerned. What can be confusing is "135x10 axle" could be taken as referring to a standard repair axle of given dimensions (in this case 146mm long with M10x1 threads) that a common cup and cone hub would use, like what a typical Shimano or OEM brand mountain/hybrid/etc hub would want if its axle got stripped or broken. Your 370, like most fancy cartridge bearing hubs, takes a specific proprietary axle with shoulders, flat machined spots, etc.
The stub of external thread is what the axle hardware threads on to, what you use to adjust the bearings, etc. It does in fact contact the frame. This can be counterintuitive, but the other counterintuitive thing is the very high amount of clamping force provided by the QR skewer. As long as it's clamped down adequately, that connection is keeping the axle from rubbing against the frame in a way that could damage anything.

Also, 9mm is associated with QR front hubs, not rears.


Chain coming off with internal hub gear bike - why? I have a Raleigh Caprice bike, about 7 years old, with sturmey archer 3 speed hub gears. There have been some problems with the hub gears in the past 9 months, which have been fixed by a mechanic.

Recently I had a puncture, and since taking the back wheel off to fix it, the chain keeps coming off and refusing to stay on. There is an unexpectedly loud 'bang' noise when it comes off.

I thought maybe I had not put the wheel on correctly (despite having done it several times before), so today I checked it all over.

There's no problem with the alignment of the wheel, the chainline looks fine, the chain isn't excessively worn and doesn't appear to have any stiff links and the wheel seems to be true. I put all the components relating to the hub gear back just as I always would before, and all the bolts seem adequately tightened. The chain is a bit mucky, but I don't think excessively so.

When I have the bike on the stand, I can turn the pedals and change through all the gears without problem. But when I try to ride it, the chain comes off. The first time today it came off as I moved the pedal backwards slightly to get it in the right position, but after I put the chain back on it happened again without any backpedalling. I think the chain is sometimes coming off at the front and sometimes at the back.

What else should I check or try? Could the internal hub gear be at fault?

I also thought I should check the cog that holds the chain at the front (chainwheel?), but I didn't really know what to look for. It did look a bit dirty/greasy but the teeth looked the right shape.

I'd be really grateful for any advice!

In short: If chain comes off with horizontal drops (typical internal gear or single speed) the wheel has to be too far ahead. Try pulling wheel backwards until the chain can be moved <5 mm and tension the wheel properly.

Other possible issues are:

bent chainring or sprocket
wheel not installed properly
failed bearings in hub or bottom bracket

Worn chain is very unlikely. Also broken internal gears don't drop the chain.


Which states or countries have stop-sign-as-yield laws for bicyclists (Idaho stop law)? In Idaho (PDF), bicyclists are allowed to treat stop signs as yields, and red lights as stop signs (essentially; see the actual law for details). This seems like a very reasonable approach, balancing the fact that bicycles are smaller, more maneuverable, and less dangerous for crossing intersections against the fact that you still do need to stop at red lights and be safe when going through intersections.

Are there any other states or countries that have similar laws?

  49-720. STOPPING — TURN AND STOP SIGNALS.

  A person operating a bicycle or human-powered vehicle approaching a stop sign shall slow down and, if required for safety, stop before entering the
  intersection. After slowing to a reasonable speed or stopping, the person shall yield the right-of-way to any vehicle in the intersection or approaching on
  another highway so closely as to constitute an immediate hazard during the time the person is moving across or within the intersection or junction of
  highways, except that a person after slowing to a reasonable speed and yielding the right-of-way if required, may cautiously make a turn or proceed through
  the intersection without stopping.
  A person operating a bicycle or human-powered vehicle approaching a steady red traffic control light shall stop before entering the intersection and shall
  yield to all other traffic. Once the person has yielded, he may proceed through the steady red light with caution. Provided however, that a person after slowing
  to a reasonable speed and yielding the right-of-way if required, may cautiously make a right-hand turn. A left-hand turn onto a one-way highway may be
  made on a red light after stopping and yielding to other traffic.

Utah also considered it, but several groups including a large group of experienced bicycle commuters opposed the change.  The main reasons are:

It further designates cyclists as a "different" road user, possibly making it easier to limit our access to the roadway.
It has the potential of increasing the conflicts at intersections (the most dangerous area for cyclists) because cyclists can behave differently than other vehicles, and motorists may not know what to expect.

While I like maintaining momentum, and recognize that I can see farther, sooner than motorists, I believe that being predictable is more important.


Chain not fitting chain ring I just bought a 21-speed hybrid bike (Wal-Mart grade Schwinn) and to try to customize/simplify things (other bike is a fixie road bike), I removed the front deraileur and bought a new single-speed front crank (Origin-8 Track/SS Crank) from my LBS. By local I mean 1hr away.

Got home, did the swap, and put the chain back on, and it doesn't fit on the chainring correctly. I measured my chain and the links are the standard 1/2", but it seems like the teeth in the sprocket are slightly longer than that; eventually as the chain goes around the ring, the rollers come out of the "valley" between teeth and a roller ends up on the tip of a tooth. (Photos below)

The shop is closed for the weekend and it's driving me crazy trying to find an answer. From my understanding, all bike chains have a standard 1/2" link length, it's just the width that varies. Anyone have any ideas?

All chains are the same link length, but there are different widths. Some single speed components require a 1/8 inch chain, while the chain that come with your bike is probably 3/32. You will have to get a new chain or exchange the chaining for one that fits your chain.


While on a ride, realised rear disc rotor was contaminated, what could I have done? Last night, commuting, I got lots of dirty water all over my back brake (Promax Render-r mechanical disc), as well as on most of the rest of the bike, and me. I wiped the rotors with a clean rag to get the grit off, because light braking made an unpleasant grinding sound.  This morning I was about 30km into a rather long ride when I realised I had essentially no back brake.  I don't use the back much except to hold back on descents, though I do normally take up the slack when stopping, so it was the first  decent descent when I discovered this.

I can only assume that the water was oily (certainly possible given the state of the roads and the deep puddles last night) and that I spread it evenly over the disc.

So I ended up riding 250km with essentially no back brake.  I would have tried cleaning the rotor with an alcohol sterilising wipe from my first aid kit, but they'd dried up.  I did get a bit off slowing (not stopping) power from holding the brake on all the way down long descents, and cooking it, but presumably this just moved the oil to the pads and finished them off.

I've ordered new pads (front and rear), which I needed soon anyway.  I plan to degrease the rotor, put the used front pads in the back, and see what happens.

Now I've had the chance to remove the wheel and pads, the moving pad on the rear is unevenly worn -- much more wear towards the centre of the rotor.  It was seated properly; I checked after takling the wheel off and before taking the pads out. I don't know whether this wear was cause or effect, as I had the back brake on hard on most downhills for the little effect it did have.  There are some scratches on the back rotor but not much more than the front (or the MTB) and nothing deep like I'd expect if there was a bit of grit preventing proper contact.  The pads were by no means clean but not gritty either.

But what could I have done at the side of the road? There were no bike shops around, but convenience stores and I could probably have found a pharmacy.

Oil and contaminants from the road will float to the top of these puddles and get on the rotors.

Unfortunately once rotors are contaminated, it is EXTREMELY difficult to decontaminate them due to the porous nature of the steel they use for the discs. When you throw fresh pads on, the rotor can contaminate the pads again.

As far as brake pad decontamination, there is hope. What we do here is

Heat the pad up with a blow-torch to expand the pad material
Spray a degreaser on the pad until it stops evaporating instantly
Sand the pad with 120 grit sandpaper until you see new pad material
Clean the pad off by hitting it with the blow-torch or isoprop-alcohol
Reinstall

As far as what could be done on the side of the road, you can try tightening the barrel adjuster for your brake until you can get some form of grip or wiping the contaminants off with the inside of your jersey (That's about it).

If you suddenly lose braking power to both wheels, you can try what BMX riders do and stick the heel of your shoe between the top of your rear tire and your frame.


Sources for vintage or reproduction decals? What sources offer reproduction decals in the vintage Cannondale (lower-case, non-italic) style? When I finish restoring my bicycle's polished aluminum finish, I would like to apply replacement decals. I've examined some products offered on eBay, but none match the really old Cannondale logo.

From my experience with custom/stock graphics you've got three options:

Manufacturer: Contact the manufacturer, in this case Cannondale, and see if they have any sticker sheets available. Sometimes they'll have old stock, but more often they only have the last few years.
3rd Party: Look for someone selling sticker sheets or vintage logo sheets. Sometimes they may have one but not advertise it because it's not popular.
Custom/Make your own: Definitely the most time consuming option, but if you have a decent photo or reference, you can recreate the logo in your design studio of choice (Inkscape, Illustrator, etc.). Or, you can find someone to make some for you.

I recently did option 3 for a GT bike that I had powder-coated. I really wanted their new logo with the wings, but all I could find was the old GT letters. All told it was about $40US to get the decals (and extras) printed.


Is it possible to service rear derailleur pulleys? The outer pulley of my RD-M735, when spun, sounds scratchy and feels slightly grindy as if there is a tiny piece of dirt/grit that has fallen inside.

I have literally soaked it in WD-40 and then 3-in-1 oil and also, motorcycle chain oil (scottoiler oil), whilst spinning the pulley and it is a lot better than before. But it still catches now and again when turned by just finger tip, and sounds slightly dry and grindy. It will turn under two finger pressure though.

Therefore, I was wondering if the pulleys are serviceable, inasmuch that one can access, clean and repack with grease, the ball bearings, or  replace the bearing (that I presume) are/is within the axis of the pulley?

Yes, the pulleys of your rear derailleur can easily be removed, cleaned, greased, and re-lubricated. I'd recommend doing so about every 500 miles depending on your climate or whenever they start to sound gritty again.

If you haven't yet, I recommend reading all the Park Tool drivetrain care topics.

Steps 9 through 13 particularly on this page should cover the pulleys:

https://www.parktool.com/blog/repair-help/rear-derailleur-overhaul


Tubular Glue vs Tubular Tape I'm looking into going for tubular tyres and I'm new to this part of the world. As far as I understand there are two main options to mount the tyre:

1. Tub Glue which sounds like kind of a pain in the ass time-wise and requires some effort, but seems like a very solid solution to fix the tyre to the rim.

2. Tub Tape like the one from Velox, which seems like a very easy and fast way to mount the tyre but for me personally it doesn't seem rock solid.

Can anyone with the experience of using both explain pros and cons of these methods.

Thank you guys! You're the best!!

I've glued hundreds of tubulars and learned the craft from some of the best mechanics in the sport including a former wrench with the Motorola team and a former Mavic Service Course mechanic. These days tubulars are really only used in cyclocross, track and at the very top level of the sport.

There are some very distinct downsides:

Safety. Improperly glued tubulars can roll off in a corner. This is not to be taken lightly. Even top pros have rolled tubulars (Joseba Beloki famously went down hard in the 2003 Tour de France, effectively ending his career) On a long descent dragging your brakes can heat up the rim enough to soften the glue resulting in a rolled tire.
Expense. A decent tubular costs significantly more than a good clincher.
Repair. You can't patch a tubular during a ride. You pretty much have to replace the entire tire. This means you need to carry at least one spare tire per ride (and hope you don't get more than one flat!) This BTW pretty much negates any weight savings which are trivial to begin with.
Hassle. Mounting tubulars is a multi-day process, especially if you're mounting them on bare rims for the first time. Getting the tire onto the rim is significantly more difficult than mounting even the toughest clincher.

Now, all that said if you're going to move forward I strongly suggest using mastik instead of tape. Tape isn't that much less messy and the bond seems to be less consistent then a good gluing job.

Park Tool has as good a guide as any on mounting tubulars as anyone: http://www.parktool.com/blog/repair-help/tubular-tire-gluing

A few other tips:

Do NOT use 3M Fast Tack! Some people swear by the stuff. I've personally seen several tires roll from using it. This is especially true with Continental tubulars. Fast Tack actually dissolves the glue that holds the base tape to the tubular casing. Someone a few years back did a study on tubular cements and Fast Tack did very poorly (http://kuktl.dept.ku.edu/bicycle/Cusa1.pdf) Stick to Continental or Vittoria.
Mount the tires to a clean rim, inflate them to high pressure (120+ psi) and let them sit for a while (as in several days). This will make it much easier to mount them.
People will tell you to put a foot in the tubular and then pull up until you hear a popping sound. They claim this is stretching the tire to make it fit easier. These people are idiots. The popping your hearing is the base tape detaching from the casing or threads in the casing tearing. Don't do this!


Identifying Rear Axle Size I've got a bent QR rear axle and am looking for a replacement. Seems that these come in 9.5 and 10 mm sizes with a couple of different threadings. When I measure the OD of the threads I get around 9.8 mm – can I assume that that means I've got a 10 mm axle?

Is the right way to measure to pull the axle and measure an unthreaded section? Or does the size even matter if I'm replacing the cones and nuts with it?

That sounds like 3/8 inch.

Take the hub to a bike shop, they'll be able to pick out a compatible axle for you.


How should disc brake rotor size scale with wheel size? I was wondering whether 20" wheels can get away with smaller rotors than 28" wheels, and if there is a correlation, if it is linear. If it was linear, then 140mm discs on a 20" wheel would be equivalent to 200mm discs on a 28" wheel (and it would be unnecessary to mount anything bigger for pretty much any application).

At a given forward speed, the circular speed of the rotor scales up linearly with decreasing wheel size, which on smaller wheels should help with the cooling and should provide higher friction power and thus higher braking power.

But I can't find any source confirming this, so I'm asking here.

To achieve the same braking power, the rotor/wheel diameter ratio should be constant. (Assuming the caliper is the same, and assuming cooling is sufficient.)

If the rotor/wheel ratio is constant the leverage between the force applied by the road surface and the rotor is constant.

Also, because circumference scales linearly with diameter, the speed of the rotor surface at the caliper, and hence friction force, will be the same.

Re heat dissipation, rotation of the disc will have little effect compared to  forward motion through the air, which will be much more effective at providing cooling air flow.

I would think that for most bikes that are not being used for sustained braking on descents an appropriately sized rotor and brake caliper has sufficient heat dissipation. I’m perfectly happy to be informed otherwise though.


Where can I find containers to dispense bulk chain lube So, I'm looking for drip style containers to keep in my messenger bag and my home shop to dispense bike chain lube. I want to just buy a 32oz container of lube for cheap on amazon and fill my own dispensing bottles since I need to clean a lot of chains on a lot of bikes.

http://www.amazon.com/Finish-Line-Bicycle-Chain-32-Ounce/dp/B001XRW0DY/ref=wl_it_dp_o_pdT11?ie=UTF8&coliid=IR73EP9U85298&colid=41YO2K2T7TMA

However, I have maybe one small bottle of chain lube, which I'm not sure how to refill (it doesn't appear to be made to be dissassembled). Does anyone know where I can find dispensing bottles that can be securely closed for transport with all the other crap in my bag?  I've checked a few science supply places online, but havn't found anything that would drip dispense and also have a screw cap.

In my experience, the best kind of lube container is the Finish Line one, or similar. It has a nozzle that can be snapped off easily for refilling, and a threaded cap which covers it all. The "secret" is the threaded cap, which actually presses the removable nozzle against and into the bottle's neck.

Then, I guess there are three ways to use it:

Buy one, use it, and then refill it indefinitely with the lube of your choice (that's what I do at home and in my carry-along toolbag. Have not had any spilling so far, and I shake them a lot while riding);
Find a product that has the same design (medicines, hair products, etc.), buy some, use them, and then reuse the containers. I found the last image I post below looking for "eyedropper bottles" on google images;
Find similar ones to buy off the shelf. I don't have experience with that.

That's what I am talking about (this is the 100ml bottle, there are smaller ones):

The "eyedropper bottles", showing the inner removable nozzle on the second bottle from left to right (with threaded cap removed):


Dog Trailer Wheel size - for commuting/touring I'm upgrading my dog's ride from our old beat-up kid Burley, to a trailer made specifically for pets. I've found one with aluminum frame that looks affordable & comfy for my pooch.... Question: would 16" or 20" wheels be better for a variety of road conditions, including off-road?  Don't want it to be so bouncy for him that he gets sea-sick. Thanks in advance!

I don't have a dog, but that means my trailer passenger can speak.

Specifically she can complain about the rough ride compared to the child seat on the back of my bike.  That's with 16x1.75s pumped up to a pressure intended more for her comfort than my ease of riding (compared to a seat with minimal padding over the top of a 700x28 at 80psi).  Trailers are much rougher than bikes, so you want to minimise that.  Go for the bigger wheels.  The higher centre of gravity isn't nearly as much of an issue as it would be on a bike, because trailers  are so much more stable.

In addition to the choice of wheels, remember that it's much harder to avoid bumps when you've got 3 tracks to keep off them, two of which are behind you and not in line with your body.  With cars around you often can't keep the nearside trailer wheel out of all the potholes. Your passenger, whether human or canine, is likely to get bumped around more than you.


Dimensions of a hybrid clip on cycle fenders I have a Fuji Absolute 1.9D cycle size 23 inch hybrid bicycle.

Would someone please recommend the correct dimensions of a clip on fenders (mudguards) that are both functional and aesthetic? (I personally prefer narrow fenders.)

Thank you in advance for your help.

Hybrids vary a lot. So do tyres and mudguards. It took two attempts to find some to fit my hybrid despite ruining thinner tyres than stock. And they weren't clip on. Your preference for narrow mudguards won't count for much if you're running quite wide tyres. Most road bike mudguards fit up to 25mm tyres. Most mudguards that fit more than that are big enough for up to 40mm (at least). These may then not fit inside your frame without being slightly bent towards the tyre.

I suggest you spend some time with a ruler or callipers at the tricky points.


Shimano Revo Shift Gives No Clicks I have a problem with my shifter. My bike is using Shimano Revo Shift(gripshift) RS-35 (see my picture).  The one shifting the front derailer (the left shifter) does not click when I turn it but it can still shift the cable.  How do I repair it?  I don't even know how do open up the shifter in the first place.

From the picture, it looks like you have a friction shifter rather than an indexed shifter. Indexed shifters click, and friction shifters move smoothly. For a rear derailleur, you would almost always want indexed shifting because the cogs are so close together. For a crankset with 3 chainrings, friction shifting can be handy for fine-tuning the position of the front derailleur.


How to fix raised shoulder posture? When riding, I have found myself in a posture where my shoulders are raised (like a shrug).  I assume this is a bad posture.  When I notice it, I correct myself.  However, sometime later I might find myself in this position again.

What can I do to correct this, besides just trying not to do it?

Is it a bike setup problem?  Can I do any exercises off the bike to improve this.

In my experience it may be a lack of core strength.  So you end up leaning on your arms more, to try and lighten the load on your mid-torso muscles and lower back.

Try moving around more at work, a standing desk might help.  Some stretches throughout your work day and before riding too.

If you don't wear cycling pants, consider getting some.  They offer support around the waist which I found helpful.


How can I prevent rubber handlebar grips from melting/disintegrating? I bought a used mountain bike recently that came with some not so great handlebar grips.  In humid weather they get really sticky (so much it hurts to pry my hands off them) and bits of rubber come off and stick to my hands.

I'm replacing them as soon as I can but in the meantime I'd like to know what I can do to prevent this from happening with my new set of handlebar grips.  Does this happen when you leave your bike in the sun or the rain?  Is it inevitable after a certain amount of time?  Is there anything I can do about it?

I remember this would happen to me as a kid while on my bmx bike especially in humid summer weather.

So you are buying new grips already - I'd say make sure they are a harder compound than whatever your current ones are. Seems like harder rubber is less likely to deform/melt away.

With your current grips you might try wrapping them in bar tape. There are many kinds. I use cork - is good for wicking away moisture from sweaty hands but it is thick. Synthetic bar tape that's thinner might wrap tighter and be less bulky around your grips. If you don't have any bar tape, maybe try the clear plastic wrap from your kitchen. It should keeps the little bits off your hands. Could be more slippery so be careful.


What bike for a long distance tour. What to change on current set up? This is my current set up. I am thinking of upgrading and changing some parts. Particularly I am interested in making the overall bike lighter, and the ride more comfortable.

Steel frame (kona explosif)
26 inch wheels (Sun Rhynolyte).
disc brakes (Magura Louise).
Chris King Headset.
XT disc hubs.
FSA X-Drive cross country cranks.
XTR rear mech.
SRAM 8 speed chain.
Shimano 8 speed XT shifters.
Extrawheel trailer.
Carradice panniers.
Tubus logo pannier rack.
Schwalbe Marathon XR tyres

Schwalbe Marathon tyres

Components I am thinking of adding

Butterfly handlebars.
Bottom bracket: alternative to SKF (like Phil Wood).
Thinner wheels (and tyres).
Try out different brands of clip-in pedals like egg beaters, or 'Time' pedals instead of the Shimano SPDs.

Focus on your points of contact and your positioning on the bike. The butterfly handlebars are a potentially good option due to the extra hand positions. Are you totally happy with your saddle? If you're considering days-on-end touring you'd better be. Pedals aren't as big of a deal if you're already riding clipless- brand is just a matter of preference there, but are your shoes in good shape? any discomfort or hotspots after long days on the bike? Finally, if you have any discomfort or pain when riding the bike, it might be worth moving some things around, especially stem length/rise. I'm assuming you have your saddle height + fore/aft where you want it. If not, play with it a bit or better yet go see a fitter with a good reputation.
Most importantly, don't change any of these things immediately before you go on a tour! You need a few long days in the saddle to test them out first. Also, if you're happy with all of the things I mentioned, don't second guess them just because I pointed them out. Be happy with what you've got and how you've got it and have an awesome ride.


If the original lube that comes on new chains is so good, why don't we all just have a unified perfect chain lube? See the following link to read about peoples opinions about new chain wax/lube (and when to remove it):
New chain is pre-lubricated, should I clean it before use?
Can we buy this chain wax/lube that Sheldon Brown(see Carson Reinke's comment in link above for quote) says we should not be removing from our new chains? Is there a perfect lube?
I do realize there are different lubes for different weather conditions and environments.

I'm currently reading this book with much much much info about bike chains, their construction and how they wear:
Everything you need to know about Bicycle Chains: A book of special insights for expert mechanics Kindle Edition
by Johan Bornman
(currently available to borrow for free if you have the Kindle Unlimited package)
The book isn't perfect, but seems to have substantial technical basis for its conclusions and recommendations, unlike (imho) most comments one reads online.  In particular, the author recommends against wax lubes as quickly being squeezed out from wear points and thus rapidly losing effectiveness and increasing chain noise.


Early Rider Belter hub maintenance My son has had an Early Rider Belter for around 14 months.  Recently, I've noticed the free-wheel sounds "gritty", and there is quite a bit of friction if you move the cranks backwards while the rear wheel is spinning, exactly as shown in this YouTube video (posted by someone else... clearly the hub has issues).

I've removed the rear wheel and taken a look at the sprocket.  It's not like Shimano hubs I'm familiar with.

Can this hub be serviced?  If so, how does it come apart, and what tools will I need?

It appears to have "KENGMIN fastace" printed on it, but a google for this term doesn't provide anything useful.

Here are two pictures of it:

Fastace is a maker of bicycle components. That looks like a freewheel with one belt drive sprocket instead of 5 or more chain drive sprockets.

See the Terminology Index for a description of the difference between freewheel and freehub/cassette systems.

The belt drive freewheel should be removable with a four tooth removal tool (see the Park Tool video below for tool selection guidance). You'll then need to get inside the freehub to clean and re-lube the bearings and racheting mechanism. I believe that's done using a pin spanner to unscrew the rings with 'KENGMIN fastace' written on it. See the RJ the Bike Guy video below for a idea how the might be accomplished - your freewheel might be a bit different, but it gives you and idea of what to expect.

As an aside, that's an interesting kids bike. Not sure I like the radial lacing of the rear wheel though.


Identify year of manufacturing of Merida frame by Serial number I'm trying to buy a used Merida Scultura Road frame, but the current owner does not know the year of manufacturing. It is possible to extract this information from serial number?

Serial:

WC 93055 B

BI - 1582 BR

Per comments from the OP, looks like a 2007 model.


Using a schrader pump on a presta valve I have a JoeBlow Sport (not a Sport II or Sport III)

It head defaults to schrader style. There was an adaptor in the box which I thought was a presta adaptor.

I tried sticking that adaptor in the pump small side (screw side) toward the pump, other on the tire presta value. No matter what I tried I could not get the tire to take air (yes, I unscrewed the lock on the presta valve)

I looked for some videos and the manual but I can find nothing on the JoeBlow Sport. Only the Sport II and Sport III which have a different head.

I found this video about some other head and how to change it. It involved opening the head and flipping parts. So I opened the head on my JoeBlow Sport but I can't see any way the parts fit differently.

If I flip the second part from the right end, it's black and rubber, it looks like I'd expect for a presta valve but it's impossible to close the head back up with it upside down. In fact I can't see any point in being able to open this head, flipping any piece whatsoever makes it impossible to close.

Can someone explain what I'm supposed to do here?

I figured it out.

I needed to screw the adaptor on the presta tire valve, then attach the pump head. I was instead putting the adaptor in the head and then pushing it on the value but it needs to be screwed on first.

I feel dumb but at least my tires are now inflated


Help determining spoke length along with an education I understand that there are spoke length calculators and I have an understanding of what variables are at play when calculating spoke length, though I remain absolutely lost when actually attempting to build a wheel in reality.

If someone, anyone, could help me calculate spoke length from a set of criteria I would be so grateful that words cannot express my appreciation. Though I want to understand how this calculation was made, so that I don't remain forever ignorant.

(Interestingly, I went so far as to offer payment for an education on a popular bicycle-related forum, and no one there was able to explain how to make this calculation—instead, I was mocked, while still no one could make the calculation. Why is spoke length so elusive?)

I want to build a wheelset from this hubset: Milwaukee Bicycle Co. Hubset - 32h

I wish to lace said hubs to these rims: H+Son TB14 700c 32h Polished Rim

Would someone be able to help me calculate what length of spoke I would need?

If you can calculate a spoke length, can you help me understand how you came about that figure?

If you can help me, I would be so grateful that words cannot express the level of gratitude with which I would be left with... You would become adored.

There are other questions about this but honestly I think the answers in them are a little oblique when it comes to actually doing it.

There's a classical formula you can find in many sources. It models the wheel in a very simple abstract way. The hub flanges are circles defined by the centers of the spoke holes and the rim is a circle defined by the end points of all the spokes when they have optimal engagement with the nipples (this is also the commonly understood definition of Effective Rim Diameter, or ERD). Here's how it appears in Brandt's The Bicycle Wheel:

You don't have to touch any real math to calculate spokes, however, because there are many different spoke length calculators out there that are based on this formula where you just plug in your hub and rim dimensions.

One of the sticky points of spoke length calculation is that the classic formula only takes into account the raw geometry, i.e. it's just describing a bunch of circles and triangles, but in real life, the rim compresses a bit when tension is applied, and the spokes elongate. How much depends on the particulars of the rim, namely its cross sectional area, and the gauge of the spokes, respectively. There are some sources out there that give specific numbers to show how to compensate fairly precisely for these effects, but in practical terms you just round down a bit, and how much depends on having a feel for what you're working with. Rounding up from the number the formula spits out is dangerous when calculating spokes because you risk running out of spoke thread, which can lead to situations where you have to struggle and maybe fail to get the final tension you would have otherwise chosen.

Many spoke length calculators invisibly do this rounding for you, but I like to use ones that don't, so that I don't have to wonder how much they're rounding, which direction, whether the amount was chosen based on the spoke gauge I'm actually using and what the tension will be, etc. The free spreadsheet-based calculator Spocalc is what I usually use. It's an .xls but opens fine in free spreadsheet software in my experience. It uses the terms "width from center to left flange" and "width from center to right flange" for the measurement your hub's page is calling "flange width." The page doesn't specify a spoke hole diameter, which is fine because you can just use 2.6mm as a generic one for most hubs. Here's how it looks with these hubs and rims plugged in:

Conventional wisdom for these wheels would be go 3 cross because that will give the spoke angle closest to perfectly tangent with the hub flange. That's generally true of 32 spoke wheels with not exceptionally large flanges.

So, at 3x we see an output of 295.6mm in front and 295.2mm in back.

Presuming the published ERD is correct, and in real life I never, ever gamble it is even though most of the time they are, in back I would do 294 with any gauge of spoke, and in front I would just do 294 as well, although with straight gauge 2.0 I'd also feel okay with 295. In this case, presuming the ERD was measured properly to represent a spoke with its tip flush with the top of the nipple, I'd expect 294 to get them both right about in that perfect range of somewhere between the base and the top of the screwdriver slot in the nipple, and with no danger of poking out the top, which I avoid at all cost. Realistically 295 would likely be fine for the front, as it may cause a slight bit (0.1-0.3mm-ish) to protrude out the top, but not more than most spoke/nipple combinations can handle. I just play it safe.

Also, everything here presumes 12mm nipples, the most common choice for handbuilt wheels. Longer nipples have more thread and change your ERD.


How to change a Gary Fisher Kaitai Dual Sport to be faster on the road? I have a Kaitai dual sport and I love the bike however, I find myself doing a lot more road riding than off road riding and am looking for things I can do to the bike that will help road rides.  I ride with another person who has a road bike and it is MUCH more efficient.  I can easily ride 5mph faster on that bike with minimal effort.  Would it be possible to change out the tires?  Tires and rims?   Something so I can more easily keep pace, without having to buy a new bicycle?

I changed the tyres on my MTB for slicker ones, The difference was very noticeable and more comfortable. Running higher pressure in the tyres also helps, but be careful not to exceed the tyres recommended max. Also I would recommend reducing the weight if you can, remove any unnecessary parts


Which component upgrades for longer rides I have a Giant Escape 1 (2016) which I use for commuting to work and back. It is fitted with Altus level kit.

I was considering taking my bike on holiday with me to get in some longer rides, perhaps some parts of the Trans Pennine Trail. Nothing too excessive, perhaps 50 to 60 miles a day, which I know is nothing to many riders, but to me it's a step up from my 8 mile commute. The trail is mostly off-road, dirt track, but nothing too rough.

Would it be worth my while in the long run considering upgrading my components to say Deore level? And if so, in which order for "most bang for my buck"? My current setup has Tektro brakes, so I'm thinking that might be a good place to start?

Any thoughts most welcome

If your goal is comfort over speed, I would emphasize in three upgrades which don't break your bank:

Find a comfortable saddle. Go to your LBS and ask their opinions. A lot of people suggest leather saddles, like Brooks or Selle Anatomica. A good saddle is expensive, but it is a worth upgrade and you will be surprised how big the difference is between a cheap saddle and a good one. If you are on a tight budget, a padded short is a cheaper option.
Do you use a bike rack and panniers? for a long ride especially on hot weather, a set of pannier is better than a backpack.
I think your current tires are already pretty good but it might be worth a try to have wider and fatter tires for more comfortable rides. I assume your current tires are 32mm wide, so upgrade to 35mm tires.


Rear derailleur got caught in the spokes, what could be a root cause I have several problems on this bike. Here are the elements that have failed and other pieces of information:

the chain has derailed past the largest sprocket
the rear derailleur has rotated 180 degrees, and is caught in a spoke (between the frame of the derailleur and one of its sprockets)
half of the derailleur is now bent 45 degrees from its frame (derailleur on picture 2 should be U-shaped, not V-shaped)
sprockets showed some signs of wear, but not to the point where it causes the chain to skip when load is applied
the threaded hole to which the rear derailleur is screwed shows some sign of wear ( this is a modular part which is itself screwed to the frame)
rear axle is broken in half right in the middle. I don't have the tools right now to open it, I believe this requires a punch and a hammer to remove the cog set.. Right now I have already lost some bearing balls after I moved the axle from the dropouts.

Now I'm wondering if there is a single failure that could explain what happened.

Thanks to the answers, I inspected the derailleur closely and found this:

There is a missing chip exactly where the L screw is supposed to hit the frame. Apart from that and the fact that it's bent beyond repair (IMO) the derailleur is actually brand new..

Here is a picture of the broken axle I  knew something were really wrong when bearing balls started falling on the ground...

If the low limiter screw on the rear derailleur was very badly adjusted, it would be possible to move the derailleur far too far past the end of the cassette by shifting into the lowest gear (i.e. shifting onto the largest cog on the cassette). This would move the chain off the top of the biggest cog and could force the derailleur into the spokes which, in turn, would bend it.

There's a lot of information on setting derailleur limiter screws on the internet - here's a fairly good example