Finding a replacement crankset (and maybe a bb to go with) I am in need of replacing my crankset on my hybrid discovery 401 - although all that is left of the 401 now is the frame and the bb/crankset.
it has a sealed bb 113/68 square taper.
I am struggling to find a triple crankset on the web that would suit, as all of them seem to be hollowtech or some other bb type.

What I am unable to work out is if any of these whizzy new types are going to fit my frame.. or what I need to check to know.
I have removed the existing bb hence knowing it's measurements. it is threaded only at one end, and all the pictures on the wiggle or wherever for different types of bb seem to have threads on both ends.
I use the bike to cycle to work each day, about 20 miles round trip, it is a 24 speed bike currently, and i have some fairly nice shifters and thus need s 3 sprocket crankset.
I also take one of the little ones in a hamax seat, or both of them in a trailer thingy.

Can anyone offer some assistance?
An square taper bb seems to be about £10 so not a bank breaker, the newer hollowtech or whatever are a little more expensive and don't necessarily want to change it all up, but finding a crankset that is square taper, and for a hybrid rather than a mtb is a nightmare. along with not really being sure on what teething to go for..

any recommendations or links happily received

Thanks

Nat

This is one I prepared earlier, the question is slightly different than the original Can I replace chainrings without replacing the rest of the drive train? but the answer suits. You have the same considerations for a selecting a new chainset as this question.

Chain line

When selecting a new crank set you need to ensure it aligns with the current chainline of your bike. If you change the chain line you may not be able to use all of the gears on your rear cassette in all gears up front.

Bottom bracket

You need to ensure that a new crankset will be compatible with your current BB spindle length and interface. (square, octo, isis, hollowtech etc.) If your BB has a lot of wear once you have the cranks off its not a bad idea to change the BB at the same time as they're not that big a cost. Also it's sometimes if you get a good deal on a crankset to get a matching BB as they're the cheaper item.

Chain length

You may need to shorten the chain going to smaller rings if the derailleur doesn't provide enough tension.

Rear derailleur capacity

Not a problem when shifting to a smaller crankset but if going larger you would need to ensure that the rear derailleur would handle the additional cogs. There are tools online to help calculate this.

Wear

If the chain and rear cassette are showing signs of wear it's often wise to replace these at the same time as they will wear a new crankset faster.

Chain width

If you are buying a new crankset it has to be appropriate for the number of gears on your bike, this is because chains are different widths to accommodate more gears on the rear cassette. The rest of the drive train is sized to fit the chain width.


Why can't my rear shifter shift into low gears? I have an entry-level Trek mountain bike bought several years ago, with a Shimano derailleur. It's been hanging in my garage for the last few years, taken down only a few times for rides. I just did a ride with some hills, when I noticed it wouldn't shift into lower gears. It feels like there's so much tension in the cable that I can't physically move the shifter below gear 5.

After spending hours this afternoon looking at bike repair videos and questions here trying to isolate the issue, I've found or done the following:

the derailleur hanger is straight
I can manually move the derailleur to the lowest position and it shifts down to the lowest gear fine
I've cleaned out the shifter with WD40, and when I relieved the tension in the cable by taking it out of the little cable holders between the derailleur and shifter (sorry don't know correct terms); with the tension gone, the shifter moved easily between gears 1-8
when I had the cable unclipped as above so it was loose, I was able to move the cable housing up and down the cable easily; it didn't seem dirty or much friction, although I noticed the rear gears and derailleur were pretty dirty

It hasn't had a tune up or any self-service in years. It just seems like there's so much tension in the cable that's preventing it from shifting down below gear 5. Also I noticed even when I can shift down from 8 thru 5 that the derailleur looks like it's barely moving. This is just when it's sitting still, although while moving I didn't have much trouble shifting between 5-7.

It's a little unclear whether the shifter is refusing to get into the lower gears based on what the indicator is showing or if it's indicating lower gears than 5 but nothing is happening in back. Also I'm assuming by "lower" you mean larger cogs and that you don't have a Rapid Rise rear derailleur.

If the shifter is clicking from gear to gear but not moving the rear derailleur into the large cogs, it's likely you need a bunch more cable tension. This is one of the more common break-in type adjustments bikes need. There are plenty of questions here about this, but the basic process is loosen the RD cable, screw the barrel adjuster(s) on the shifter and/or RD in, and fasten the cable back so that you have all the slack taken out, barely taut, then use the barrel adjusters to fine tune from there.

If you mean that it's having a hard time getting into the small cog (the high gears), then check to make sure there's not a cable housing end hung up on either a housing stop on the frame or the where it enters the shifter or RD.

If you did happen to have Rapid Rise, either of the above problems can still occur, but the symptom that goes with each solution would be switched in terms of which end of the cassette you can't shift into.

Friction in the housings could cause this problem too but it sounds like you've eliminated that. Make sure you've checked all the RD housings - bikes can have 1, 2 or 3 of them depending on the design.


front derailleur slipping? I recently started to have a problem where the chain randomly goes from the large front gear to the smaller one.

Ive been trying to work out the reason for this and would like some input on the more likely culprit:

The front derailleur is somehow slipping. in order for it to stay in the position for the large gear there is quite a bit of tension on it. (Its a 105 shimano if it makes any difference)
My front cassette is worn out AND i noticed that the chain angles towards the left as it comes off the front cassette so it naturally wants to slip down to the smaller gear.

This sounds like your cable has stretched. For the front derailleur, you have to apply tension to the cable to get it to move to the right ("harder gear") if the cable lengthens (or slips), by even a millimeter or two, it can cause the front tuning of the gear system to get out of whack with the result being the chain dropping to the easier gear(s).

Shift all the way to the left, loosen the bolt (or nut) holding the front derailleur cable, put tension on the cable and retighten. I suspect this will fix things.

Chainring wear could be at play here, but they would really have to be worn down. The chain angle you see is probably the natural movement when the chain is supposed to be shifting.

Also check alignment: derailleur should be be about 2mm above large chainring, curve roughly matching, and aligned in the same plane as the chainring.

Happy riding.


Vantara GT 6061 aluminum bike front wheel replacement? I have a Vantara GT 6061 aluminum bike and I lost the front wheel. Where can I get a replacement?

The simple answer is: any good bike store. You may not be able to get an exact match for the hub and rim GT used origigally, but you will be able to get a wheel that is functionally identical.

If you understand bicycle wheel standards, you could source a replacement wheel from an online store for little less cost, but if you do not, it's much easier to have a local bike store advise you.


Clicking sound coming from pedals/pedal spindle/crank I recently bought a Trek 4300 series MTB, but after only several weeks of use, I'm getting a clicking sound coming from both sides of the pedals.

It seems particularly pronounced when more torque is applied, e.g. going up a hill or when accelerating.
It seems to come from the pedal/pedal spindle area but it could be coming from the crank arms.

How do I go about identifying what the problem is and rectifying it?

Papuass is correct - take it back to the shop as it is under warranty and they may have offered you a free service anyway.

Here is the complete checklist for future reference...

I believe that you have a Shimano Altus chainset - a pressed steel number with no chainring bolts to come undone.

As for diagnosis, you are not getting the click when you are freewheeling - that is normally a simple check to do first.

Next, try different chainring - does the click only happen in the outer ring? This can be due to the front mech touching the crank. Also check the mech clears the outer ring with the cage staying away from the teeth.

Now try the granny ring - this will not be using the same 'chainring bolts' and will identify if the problem is there - this I do not suspect in your case due to the construction of the chainset.

Now try and pedal out of the saddle - do you still get the click? Sometimes the seat post can creak as you pedal and you need to check that is not it.

Stiff link? If the click on each power stroke then it is unlikely to be the stiff link going through the chainset as this will be  different each time.

Now for checking the pedals. There should be a smidgen of grease on the pedals and inside the crank arms. With a 15mm spanner you can take them off, check the grease and put them back in again. The pedals should be in really tight, you may want to wear a tough glove whilst putting your pedals in/taking them out. This is because you can mangle your hand on the chainset quite easily doing this. Remember that the left hand pedal has a left hand thread and the right hand pedal has a right hand thread - it is important you turn the right way.

Now for the bottom bracket. Get a socket set - 15mm and check the crank arms are on massively tight.

Check the pedals for wear/general condition and decide whether you need to tighten up the bolts holding the cages onto the bodies. There should be some play with affordable pedals - the bearings do not have to be great - but if there is too much play consider tightening them up with the socket set, or, better still, just get a new set of pedals, maybe upgrading yourself to Shimano SPD/Time ATAC.

If that has not cured it then check the bottom bracket is inserted properly. The chances are that you will need brand specific specialist tools for this, including a crank removal tool. Again you will have left hand thread on one side and right hand side on the other side. Make sure you are not doing up when you think you are trying to take off the bottom bracket.

With modern 'cartridge' bearing bottom bracket sets (you have one of these with octalink) it is unlikely to be penetrated with dirt/grime (giving rise to noise) but older square-peg bottom brackets can have problems with ball bearing cages falling to pieces and making quite a racket. Usually these can be repacked with new balls and grease, however, you might want to put in a new b/b - this will need to be the correct outer shell length and axle length - see your existing b/b for numbers.

There is an outside chance that there may be something up with the frame, older cr/mo frames sometimes have a really basic tube for a bottom bracket that can make itself ovaloid over time. This you can only determine with the b/b fully stripped out and when you try to put it in again.

With fairly accessible tools you can get most of the bolts tight, this may cure it and save you the 'trek' to the bike shop. Given your warranty situation you can return it to the shop and let them make a decision on how much they want to strip the bike down.


Brisbane - Logan cycle route question / How to find/ask about good cycle routes in certain areas Sorry if this is a bit meta.
My specific question is: What (if any) is a good route to cycle between Logan (QLD,AUS) (near the M1) to Brisbane (via the V1) for those adverse to riding on busy roads.
Alternatively, where would be a good place on the internet to ask this question?
To elaborate on my question further: I am investigating regular travel between Daisy Hill and Brisbane CBD. Once you get on the V1 at eight mile plains its easy but just before then is a bit tricky. It seems your choices are either along Logan road to where the V1 hilariously starts at a motorway onramp with not even another foot path in sight. From School Road to the V1, Logan road is 80km/h with no footpath and not even a hard shoulder in sections.  Alternatively to the east of the M1, there is school rd on to Miles Platting Road, but this road section seems to be missing paved footpath as well.
Has anyone got some tips on this section, or the journey as a whole?
I believe the V1 extension to the underwood road overpass will be complete by mid year, which would make things easier. but until then..
Thanks!

V1 is "Velocity 1 Pacific Motorway" which is a dedicated cycleway running between Lower River Terrace, South Brisbane and Eight Mile Plains. The 17km cycleway provides a safe and efficient route for people travelling by bike.  source: https://www.tmr.qld.gov.au/projects/Veloway-1-Pacific-Motorway
It is incomplete as of posting, with work progressing.  The parts that are done look functional, not exactly scenic or healthy when hard-beside the motorway.
I couldn't find a good map for the path, so assuming a start point in the middle of Daisy Hill, working with google maps suggests these two dreadful routes:
26.9 km straight up Logan Road to the "start" of V1
30.4 km doing a dogleg along Compton Rd and then north on Persse Rd.  Compton is a 70 km/h dual carriage way with no shoulder and Persse is narrow too.  Not recommended

So here's two routes for starters.

Starting at Daisy Hill Road and Chatswood Road (its where "Daisy Hill" label shows )
Head North on Daisy Hill Road
Follow onto Springwood Road
Turn right onto a series of residential side roads

Elysium Road
Minerva Street
North onto Donna Ave then Sultan St
West onto Greenview Ave
Do a right onto 30 then immediate left into Roseland Ave
Right into Anna Marie St
Left into Rothon Drive

Then I'd cross into School Road and push hard all the way to Miles Platting Rd, and then turn left onto 56. this is the worst part and frankly it looks awful.
Finally you're at the V1 and from there it looks okay from there onward.

** This route starts okay, but at the end there is a long stretch of badness.  The advantage is its more direct and 3 km shorter. **

Route #2

West on Chatswood
Southwest on Paradise Rd - the footpath here is marked as shared use, so use it
Turn into the Slacks Creek Corridor  which goes NW through Ken May Memorial Park.
West on Reserve Road
North on Kingston to Smith Street
West on Smith Street to Ewing
North on Ewing to Compton
East on Compton, then North on 95 for a total of 1.25 km of awful
Left onto pathway
Brookvale Drive
pathway
North on Pioneer Drive
North on Stiller Drive
Left into Underwood
North on Levington
then ride the hard shoulder on 95 again until you get to start of the V1 at intersection of "Gateway Motorway" and 95.

This route is more windy and has three separate pieces of badness, (curiously all on different pieces of 95) while also including several pathways which may be paved or unpaved.  Its also longer

Lastly if it was me, I'd be tempted to put several daytime rear lights on the bike, and blatt up 95 all the way to the start of V1.  I'd also ride with a rear-view mirror to keep an eye on what's coming up from behind, and I'd also be turning my head to look back frequently and make eye contact with things coming up behind.

Aside, I did locate "the world's most confusing bike path" at

              which may be relevant.
Finally - consider getting involved in Advocacy to ensure that V1's later stages don't slip or get cancelled.  This doens't mean street protests and placards, but writing supportive letters to the council and to Queensland Department of Transport and Main Roads would certainly help.


How did my stolen carbon frame bike get from D.C. to Guatamala? My bike was stolen from the downtown DC on nov 11 2017. It was locked and was stolen in the middle of the day. I had put a bluetooth device, more specifically Tile in the seat post of the bike. I figured it may help me locate my bike if its ever stolen or something. Someone with the app has to be in a proximity of the bike for it to send a signal.

Anyways after it was stolen there was no signal for months, and now it was the app says the bike was found in Compalapa Guatamala.

I know i will never recover the bike, but I am wondering what the possibilities are of how a stolen bike in DC ends up in central america?

There is a large community of people from or born to people from Central America that live in the DC area. The largest group has ties to El Salvador. The percentage of Latinos from Mexico is only about 5%.  The is a also large presence from Peru as well.  Peruvian rotisserie chicken is very good.

MS 13 has a significant presence in Northern Virginia and DC and that gang has ties to Guatemala.  It isn’t surprising that a nice stolen bike would show up there.

Guatemala also has the highest murder rate in the world so I wouldn’t go looking for it.


What fork will fit my bike? I have this bike:

http://www.bikebarn.co.nz/2015-merida-big-nine-20d-white.html

I want to swap out the forks for some rigid forks.

Please tell me what specs I should be looking at to get the right fit.

Thanks!

I have recently just done the same thing and switched from suspension to rigid forks, although with a much older bike. There are a few things that you need to know.

The first is your type of headset, it will either be threaded or threadless. If you have a stem that clamps on the steerer tube and then your handle bars clamp onto the stem, you have a threadless headset. I can tell by the picture you have linked too that you do have a threadless headset.

The second thing you need is the diameter of you headset, which is generally 1 1/8 inches for modern mountain bikes but if you can find a specs sheet for your headset it will specify. If you cant find the info for your headset, just measure the steerer tube with a set of calipers and look at this page (http://sheldonbrown.com/cribsheet-headsets.html) under "Threadless Headset / Steerers" and reference the measured dimension to identify the size of steerer tube.

Last, and probably most importantly, you will need to know the axle to crown measurement. This is basically the measurement from the middle of your front axle to the top of your forks. There is plenty of info on the internet on how to take this measurement but the important thing is sit on the bike and get someone else to measure or get a friend of similar size to sit on the bike while you do it, this will ensure the slack is taken out of the suspension. This measurement will help you to get forks that are a suitable replacement length for your current ones. This is important because your frame has been engineered to work with forks of a given length and altering that geometry by a significant amount will alter the handling characteristics of your bike.

One thing that can help make it easier to select forks is to buy models that have been specifically made as replacements for suspension forks with a given amount of travel. If you know the amount of travel of your current suspension you can buy some forks that are specifically made to compensate for that amount of travel (i.e surly instigator 1.0 forks are made to replace shocks with 100mm of travel). It is still worth checking that the axle to crown measurement is similar to your current setup as they can vary in size by manufacturer. For example my original forks (2002 Rock Shocks Judy C) originally only had 80mm of travel but they are relatively long and I needed the Surly instigators to get the correct length. (They work awesomely well, by the way).

When picking new forks also make sure that they have the correct brake mounting fixtures. You will often need to specify for disc, or cantilever, or both. When you get the forks, it is probably easiest to take them to your LBS and get them fitted as they will need to take the fork crown race off your current forks and move them onto the new ones. This is best done with specialist tools, you can do it yourself, but it is not worth risking the damage to components as the crown race is specific to your headset and you may be up for a new headset if you damage it.

Also make sure the new forks are made for your size of wheels, 26, 27.5 29 etc.


Use disc fork on an Lynskey R260? I got a great deal for a Lynskey R260, that is set for caliper brakes. I'm building my first bike from scratch and am thinking of using disc brakes on the front fork. Is there any reason why I wouldn't be able to use this fork with the R260?

I understand I'll need to use caliper brakes on the rear. Is it possible to mix and match?

Yes, you can use that fork and mixmatch components. Of course you'd have to check parts compatibility, here's what to look for:

Stock and replacement fork rake/axle to crown measurements. Pro Carbon Road #2, which is offered as a stock option for that frame, and Pro Carbon Road #5, which you want, both have rake of 45mm and axle to crown of 368mm, so everything's good.
Then make sure the frame accepts you fork of choice steerer type (i.e. 1-1/8 to 1.5 Inch Tapered). Again, these match, so good here too.
Fork crown shape. Totally not the issue in your case, but some frames/forks have weird crown shapes that pretty much lock you into specific vendor options.

The rest comes down to components choice:

What brake levers are you going to run? Options are: a) full mechanical, b) one mechanical and one hydraulic (but the shape might be too different) and c) full hydraulic (there are hydro rim calipers, but make sure those will work with the frame).
You'd have to build a custom wheelset or purchase front/rear wheels separately. Rear QR and thru-axle in the front is no problem at all, I run the same and some bikes come with such a setup out of factory.


Is changing wheel necessary to use a freewheel with different number of gears? Approx. 3 weeks ago I found an abandoned frame (including handlebars, fork, brakes, pedals and shifting gears attached to it). I decided to use it to build a new bicycle since only recently I've decided to learn more about these things (even though I have been riding a bicycle since the age of 3 :D). A friend of mine gave me an old MTB 2 months ago for spare parts if I need any. I decided to use the wheels (including the freewheel hub on the rear wheel) since they seem to be in order especially after cleaning and oiling the bearings and axle, and diameter-wise they are a perfect fit - 26 inch (actually my initial intent on mounting the wheels on the frame was to see what wheels would fit on it).

The problem I'm facing is that according to a friend of mine the shifting mechanism is meant for at least 8-speed rear freewheel hub while the freewheel hub the wheel from the old MTB has only 6 cogs.

My first question is what the model of the shifting gears is? The only thing that I have found are the labels on the various components that are part of the whole gear thing and they seem to be all part of a Shimano Deore XT set. Sadly when I looked online I found out that there are like 10 or so versions of this set throughout the years since the initial release. The parts look relatively new so I would exclude all models that are older than let's say 2005-2006 (correct me if I'm wrong). Is it really meant for 8/9-speed?

My second question is if it's possible to change the freewheel hub with a 8/9-speed without a need for replacing the whole wheel itself? The question of course applies only if the answer to the first one is "Yes, this is not a 6- but a 8/9-speed freewheel hub". This is probably a dumb question but since I've just started learning I don't want to screw things up. IMHO it shouldn't be a problem for close values (like 6 vs 7 speed if such a thing exists) since (to my understanding) rear cogsets with lower number of cogs have a greater distance between adjacent cogs while cogsets with a higher number of cogs have a smaller distance between adjacent cogs which makes me believe that in terms of width cogsets are in general similar enough and I shouldn't be bothered when switching on freewheel hub with another. I have another freewheel hub with 7 cogs from my previous bicycle and based on the measurements I've made the width compared to a 6-speed cogset is very small.

Below are some photos of the gears I have. Cleaning is currently undergoing so don't mind the rust and dirt. :D

If you need more information/photos I can provide these.

UPDATE: After doing some testing and also after looking closely at the rear derailleur I found that it's a Shimano Deore XT RD-M760 which - according to multiple sites - supports 7,8 and up to 9 speeds. I actually have a 7-speed freewheel hub from my previous bicycle however I am considering buying a 8-speed one. The chain I bought is a KMC Z8S which has 116 links in total (I have cut it to fit my wrong 6-speed configuration but I have a spare master link plus the rest of the chain so I should be able to recover from this mess :D). The labelling on the casing says that it's meant for 18, 21 and 24 speed systems hence with the 3 speeds on the front I can use this chain with a 6, 7 and 8 speeds on the rear. However due to my gear I have to stick to either 7 (that is 3x7=21) or 8 (that is 3x8=24) speed freewheel hubs. Given that I have an indexed shifter (as pointed in the comments) and some research I did I should go for an 8-speed freewheel hub, right?

Despite what others have written, you DO NOT need to match the number of gears on the rear wheel (cassette) to the number of positions on the gear shifters, especially for older shifters.
Many 5, 6 and 7 speed shifters have a "hidden" click, which can thus be used to control the derailleur into the extra position, but conversely, if you are using a 5, 6, 7 or 8 speed cassette with a 9 speed shifter, you will simply not use the 9th position on the shifter.  So long as the end stops on the derailleur are adjusted correctly, so the chain does not fall off the largest or smallest sprocket on the cassette, everything else will be fine.
Some have written very complicated forums and blogs about how Shimano, and others, have changed their design over the last few decades, and you MUST match the shifters to the derailleur to the cassette.
All I can say is that I, like many many others, mix and match whenever we have a need to, and often use 8 or 9 speed shifters and derailleurs with 6, 7 or 8 speed cassettes, with absolutely no issues and perfect shifting.

I currently have a 9-speed cassette on a 1990s MTB with 7 speed shifters; when riding it near home (I live in a flat part of the country) I have it adjusted so I can use gears 3-9 (using positions 1-7 on the shifters) and simply 'forget' about the other two ratios.  When I take it to the hilly parts of the UK I adjust the end stops and take up the slack in the cable so I am using ratios 1-7 on positions 1-7 on the shifters, and 'forget' about the smaller ratios.  This way I have the best of both worlds, with just ten minutes of adjustment between the two, and can source from a much wider range of cassettes, as 8 and 9 speed are still being made by a number of manufacturers, whereas 5, 6 and 7 speed cassettes are not (AFAIK).

Regarding chains, there is some variation: Shimano make chains that are good for 5, 6 and 7 speed systems, and narrower chains for 8 and 9 speed systems (and later really narrow for 10 and 11 speed systems).  However I use SRAM chains and they are compatible with 5-8 speed systems (?) or for 7-9 speed systems (?) suggesting there is some overlap.  Having ridden for over 25 years, around 4000miles a year commuting, leisure and cyclocross, I use SRAM "7-9 speed" chains on all my bikes, whether they have 7, 8 or 9 speed cassettes, and have not had any problems to date.

As you have a bike with XT parts (which some consider to be the best MTB groupset available) you could do a lot worse than stick with an 8-speed system using XT and Dura Ace parts.  I have a Dura Ace equipped road bike ("downgraded" from a 9-speed system for reliability on longer rides) and an XT/XTR equipped all-terrain bike (as I mention above, I do not live in a mountainous area, so it is used on gravel tracks, forestrty commission paths and urban cut-throughs overgrown with stinging nettles and broken glass!) also 8-speed which both give me the same range of gears as from a 9-speed system, but with, so far, 100% reliability after more than 10,000 miles of riding.

As regards "possession of stolen goods"; posting photos on a forum is not the best way to go!  Even if you suggest that you "found" a bicycle or parts, I would not post photos online, as the original owner might take umbrage and want it back.  That said, I "found" a bike over 20 years ago and took it to the police station; they kept it for three months and then let me have it back because the original owner did not come forward to claim it.  I built it into a touring/winter training bike, and have covered about 50,000miles on it, so am happy that I will not be prosecuted, as the police followed procedure for lost/found property and passed it back to me.  Legally I will never be the "owner", but in reality there is no way now for the original owner to prove my bike is their bike and claim it back...

As regards an "XT spec bike" rarely being abandoned; I would invite anyone to come and look around my town.  It is not a "university" town/city, but we have a college and uni campus here, and every week I see £200 and £300 machines abandoned because of a buckled front wheel, broken chain or mangled derailleur.  After a few weeks they are robbed of parts (lights, front wheel if not locked seperately, saddle if quick release, etc.) and then slowly they go rusty and are removed by the council for scrap.  I would hope they would remove them after 3-4 weeks, before they go rusty, store them for the required 3 months, and then donate them to a local recycling charity so they can help those in need in this country or abroad, or else sold to a new buyer with the funds going to help charity.  What this needs is a change in the law to allow "ownership" of anything abandoned for 90-days or more whatever and wherever it is on public land e.g. cars, bicycles, old furniture, etc. provided the police or local authority have seized the goods, checked the details and held them for the requisite period.  We will reduce the amount of bicycles etc. going to landfill or scrap, and help charities and third world countries to become mobile in one go.


What is the actual cable pull of brake levers? I understand that there are 2 brake lever cable pull standards:

Standard Pull Levers
Long Pull Levers (for V-brakes and disc brakes)

But what is the actual difference in pull? And specifically: what is the maximum travel caused by the lever on the cable (in mm or in inch)?

A long pull lever (i.e. for V-brakes, mountain mechanical discs) pulls the cable about twice as long (but about half as hard) as a short pull lever (caliper, cantilever, road discs).

This is determined by the distance between where the cable ends and where the lever pivots. According to this thread, its significantly lower for short pull than for long pull with some variation (it seems like under 30 mm is a cutoff for short pull to long pull if you're picking a lever out of the bin). Park Tool states that the distance from cable end to lever pivot is around 21 mm for short pull (around 42 for long pull lever), and with a 20 degree movement (think the cable end to lever pivot distance as a radius of a circle - with this radius, and the angle at which the lever bottoms out, you can calculate the total possible cable pulled), you pull about 7 mm of cable for short pull (versus 15 mm for a long pull lever).

Obviously, there is some flexibility in this parameter, allowing different manufacturers to design different cable pulls to get different sorts of lever feels. This can also be adjusted on the fly with systems like Avid's Single Digit line of brake levers. Someone claims the adjustment on the Avid Single Digit levers is enough to run short pull (YMMV). Usually when you buy a brake (or lever) from Shimano or SRAM, the manual specifies an "optimal" lever (or brake) to pair with.

If you run long pull lever with short pull brakes, it will be easy to pull the brake, but very hard to apply braking force with a hard lever feel. If you run short pull lever with long pull brakes, you will likely bottom out the lever before stopping (or lock up the wheel) with a soft lever feel. So, make sure to match the pull of the lever with the brake for your safety (obey the manual, except at your own risk!).

You can switch between the systems with a travel agent. Some levers also have a switch which can work with both types with the flick of the switch (Shimano ST-EF65 shifters+brake levers, for example).


Should I put my wider tire in front or in back? My used bike came with a 700x28 tire in front and a 700x23 tire in back. Should I leave the wider tire in front, or should I switch the tires? What benefits or drawbacks are there one way or the other? Is there any particular reason why the previous owner might have chosen non-matching tires? Is there any reason I should go out of my way to buy a new tire to make them match?

The found a little bit of information about tire sizing, but I still don't feel like I know what to do.

Generally on a road bike it is considered better to run tires of equal size.

There are a few newer tires which are designed to run different sizes front and rear, but they are usually within 2 mm of each other. (Like the Continental Attack/Force combination)

I would consider a jump from 28c to 23c somewhat large.

That said, run the larger on the rear. The higher air volume will make for a more comfortable ride, and the narrower front tire will steer quicker, which makes for more reactive handling, and has a better aero profile, (which may or may not matter to you).

The comfort part will matter though, and I'd say that's a trump card.


Gears shifter kinda working On my bike for some reason [when changing gear] it some times skips a gear and stays on a gear I'm not wanting to be on.

If you can help me please do so.

Here are some things that can cause that:

The cable needs to be adjusted either at the derailleur or at an adjustment on the cable. This is the most common cause.
The chain, cable, and/or derailleur may need to be lubricated.
The chain my be worn out (stretched). You can check it with a special tool, at a bike shop, or by seeing how much you can pull off the large sprocket.
The cassette (rear sprocket) may be worn or have teeth missing.
There may be a problem with the cable routing, or maybe it's about to break. Make sure then ends of the cable guides are in their proper place.
As Argenti mentioned, the derailleur or derailleur hanger may be bent.


Shimano 6 speed cassette I have a new bicycle, my first with multiple gears. The shifter is on the right handlebar. Does gear 0ne on the shifter indicate the smallest wheel on the cassette or the largest wheel on the cassette? If I am climbing a hill do I need the large wheel or the small wheel?

Gear 1 indicates the largest cog on the rear.  It will be the easiest to pedal and make you go the slowest for a given pedal speed.  You want lower gears for slow speed, whether from going uphill, being lazy, or whatever cause.  They allow you to maintain your desired pedaling cadence.


How do I determine parts for my bike and where to source them (new)? Do bike shops have specs guides or manuals to know which (eg: integrated headset bearings) parts to use on which bikes? And where do they source said parts (other than from the bike mfr)?

And most importantly: where can the average Joe like myself get this info and buy parts?

The bike I'm currently working on is a 2011 Scott SUB 30, but I can't seem to find any information about specific componentry online. If I were to take it into my LBS I'm sure they'd have no trouble figuring out where to buy, eg, the correct drailleur hanger or headset bearings.

How can I do the same? Important note: I live in Canada, so would prefer not to pay large import taxes from international sources if possible

You should look your bike up online, you should be able to find a stats page that will give you some general specs.  The shops I have been in do not have a "manual" per se of what frames conform to which standards.  It's generally done through experience and visual confirmation/measurement of the bike in front of them.

Derailleur hangers are generally purchased from the manufacturer, but there are some aftermarket ones that will fit specific models of bike.

Bike shops buy parts from a wholesaler (like QBP or J&B).  Most wholesalers won't deal with an individual unless you have a storefront (business) and $X amount of insurance.  You can find businesses online (Colorado Cyclist, Bike Nashbar, Performance Bike) that sell parts online, but realistically you are probably better off buying from your LBS and developing a relationship with them.  Oftentimes, the prices at your LBS will be similar to online without the shipping.

Derailleur hangers are one of the few things that are manufacturer specific.  Most other parts conform to some standard and your average mechanic or shop rat will be able to look at your bike and determine what type you need.


Best value for money on aero wheels I cycle to work three times a week over a distance of 13 miles in both directions. I do approximately 20mph most of the way there and back and I am looking for ways to speed up the commute.

Having read around the material online, it seems a decent set of wheels give the best performance increase per pound spent.

So the question is what wheelset should I invest in?

You can get models that claim to be Aero that range from a hundred pounds up to the low thousands. What would you recommend for a commuter?

A related but more searching question: would I even notice the difference at my level of performance?

Over a 40-minute ride, you may not notice much.

One older reference compares a then-standard 32-spoke 27" wheel to an aero rim with 28 bladed spokes, a high-end hub and an extra-lightweight tire. The estimated improvement over a one-hour time trial at 23mph was 44 seconds - an impressive improvement for racing, but not particularly meaningful for a commute. A more recent comparison by Rolf to the aerodynamic Mavic Ksyrium claims that their $2500 TT85 full-carbon disc wheelset saves 1 minute, 49 seconds over 40km.


What type of chain lube is best for winter riding? I've read a lot about wet vs dry chain lube and there doesn't seem a definitive answer on whether to use wet or dry chain lube in the winter. Some forums are full of people saying they only use dry lube because it doesn't wash off as easy, then other forums are full of people saying the opposite, for the opposite reason!

What type of chain lube is best for winter riding (water, gritted roads etc)

Personally I would go with the finish line wet as opposed to the dry.

Typically I use the dry if I want something that will keep my chain looking clean as well as lubricated. From personal experience I have found that I need to reapply the dry lube more often.

I will use a wet lube, sparingly mind you, for the nastier conditions.

Having wasted your time with that I would say that storage temperature/location, how you clean the chain (method, frequency and intensity) and how you apply the lube (gobs vs. sparingly on each link) is more important than the type of lube.


Stopping interference between LED lights and wireless cycling computer My LED lights seem to be causing my wireless cycling computer to not pickup the signal (suggested by the manufacturer and verified through tests at home).

What strategies/options are there for reducing the interference outside of repositioning the computer (since I've tried all available positions)?

Because the items are going to have to remain in close proximity, it's unlikely that there is anything that will completely solve your problem, but there are a couple of things you can try.

If the lights are wired, it is possible that the wire is working as an antenna, and you can use a Ferrite Choke or two on the wire.

Tape one near where the wire leaves the battery, and another to where the wire lead plugs into the light.  The can be found at stores like RadioShack for a few bucks.

If the lights are wireless, aluminum and tin foil is an excellent reflector for this kind of Electro-Magnetic Interference (EMI).

The first step would be to see if foil will help.  Try wrapping the outside of the lights with foil and repeating the tests you did before.  I doubt you can add foil to the computer because this will interfere with it picking up the wireless signal from the sensors.

If that reduces the interference you can tape the foil to the lights, carefully cutting away the foil around mounting brackets and buttons and see if the EMI is still reduced.  If the lights can be easily disassembled you can try taking them apart and lining the interior with foil as well; take care not to short out the internal electronics.

Good Luck.


What kind of road tyres should I go for winter commuting? I currently have kevlar vittorio rubbino tyres on my road bike, but they don't have enough grip for the oncoming uk winter conditions. What level of tyre tread do I need for road commuting on uk winter roads and any recommendations welcome. I would still like to maintain a low weight and good rolling resistance.

I used Swalbe Marathon's last year without too many problems. As has been previously said, the narrow (25mm) tyres do help cut through snow, but when you are on ice nothing is very good.

I liked Continental Top Tourers previously.


What front derailleur is this? Want to replace/upgrade Hi I've bought a foldable bike and am thinking of changing the derailleurs to Shimano, but I could not figure out what type it is.

The link the to the bike is:
https://www.forever-bicycle.com/html/show-22-29-1.html

It says MICROSHIFT FD-42F could not find it on Microshift's website .. and googling seemed to only give results to the product pages of the bike itself. Any chance that this might be a customized item?

To further this question:

If this FD is a customized item .. what are the other alternatives I have? Or is advisable to just switch to internal rear hub?

Its called a "braze-on" front derailleur.

The matching opposite format is a "band-on" or "band clamp" and goes around the seat tube.

Be careful when torquing the single bolt in your braze-on fitting.  Too loose and it will move while shifting.  Too tight and it will strip the thread and move while shifting.

Separately - the cable is disappearing downward, so it can be described as "Bottom Pull" or "Bottom Normal"

I can only see one other chainring, so this seems to be on a bike with a double chainring.

Answer Its a braze-on bottom-pull front double mech.

If your question is about groupset - look closely for engraved or embossed model numbers.  I can't recognise it.

The front derailleur is not a critical part and given its more about brute force than finesse you can get away with a very low groupset front mech perfectly well.   Sora and Tiagra will work fine with a 105 or ultegra rest-of-system, with some minor variance based on chainring separation distance.


Suggested maintenance for rear shock between service intervals? Typical rear shock has a suggested service interval around 150 hours or a year.

What is a suggested maintenance between those service intervals? Just oil the stanchion from outside? Any technique to do that because it is harder to pass the oil by the stanchion than with a fork?

Is the suggested interval a rule which should not be negotiated much or is it rather a recommendation which can be prolonged in case of less dirty rides (mud/wet).

It really depends on

the conditions you ride in - wet and muddy or very fine dust may require more frequent tear downs.
whether or not you use a shock protector e.g a Lizard Skin

IMO use one if you can but your frame may not allow a protector to fit in.

the age of the shock and the condition of the wiper seals.

Again if the wiper seal is letting dust and water through the inner grease will become contaminated and useless.

Im using a Lizard Skin and I pull apart my current Fox about every 6 months which is often enough for me as the inner grease seems a little dirty by then. I'm typically riding 3-8 hours per week in summer and 1-2 hours in winter.

Greasing the outside will do nothing other than lubricate the wiper seals slightly.

To maintain you need to

Clean all the dirt off the exterior of the shock. Give it a scrub in the sink if need be.
Depressurise the shock.
No really, depressurise! Open up the air can. I can do this by hand but you might need a strap wrench for your shock model. It should have normal screw polarity so anti-clockwise to wind off. Be careful of how you do this so you don't break off adjustment levers.
Clean away all the old grease and any dirt on the wiper seal surfaces.
Place new Shock Grease on the inner O rings, damper shaft and wiper seal. Go easy here as you don't want to block ports. Less is more. Buy a tube of real shock grease. It's expensive but lasts forever.
Screw the air can back on. Again be careful as the can is made of aluminium and has fine threads which you don't want to cross. It's not going to be really easy as the negative chamber will seal up and resist compression.

Watch the procedure in this video:


My old pedals don't spin freely, is it worth lubing them? I have a bike that has been left outside and unmaintained for a while, so now I'm trying to fix it back up.

One thing I notice is that the pedals don't spin freely if I flick them with my foot. I don't notice it much when I'm riding, but I assume it reduces the efficiency of the bike somewhat.

Is it worth lubing them or this this probably fine?

If so, what's the best way to lube them to make them more efficient?

Some pedals don't spin particularly freely from new. This is OK as the friction does not increase with load and is a tiny power loss. Often happens on MTB pedals to get a tight seal to keep rubbish out - after a short time rubbish in the bearing costs more than the seal in terms of power loss.

If the pedals used to spin freely, you possibly throwing away a few watts away as the lack of spin will be friction in the bearings and will get worse under load. Also consider that that friction is probably wearing the moving components faster than they would if well lubed.

Lubing them could be as simple as a drop of oil (wet chain lube) in between the bits that move, or a complete strip and grease.  Personally I avoid the 'complete strip and grease' as I find by the time pedals need that I prefer to save the time and install new ones.

I would go with a drop or ten of oil (left overnight then wiped off) as it will probably help a little and is worth a crack.


Rotors bent very slightly but no rubbing. Is driving safe? I just bought Rockrider 520 with Tektro Auriga Comp hydraulic disk brakes on it. I didn't ride it yet.

Both brake rotors have a very slight bent and no rubbing. Just nearing both pads every round and braking power seems good. (For me as an unexperienced rider.)

I did a caliper alignment by loosening two bolts, brake hard and tightening. Before this there was slight rubbing every round.

Am I supposed to do something? Is this normal? Is driving safe?

A slightly warped or bent rotor may cause some brake pulsation. The rotor can be straightened with a Park tool DT-2 truing tool. I have had good luck using a large adjustable wrench. Close the jaws around rotor and gently bend the rotor. You most likely won't get it perfect but you can get it back to usable condition.


Back rack good for commute? Doing commute and thinking about buying a back rack for my bike to put my backpack on.  Since the bag causes me to sweat.  Do people who have back racks on their bike find it useful for this purpose?

Counter to the answer that 'cmaster - reinstate monica' gave, you CAN put your backpack directly in a basket on a rack. It's easy!

Install a rear rack as many other answers suggest. If you're not comfortable doing this yourself, have a shop do it for you. Get a full rack, not one that relies on just clamping to the seatpost.
Get a milk crate as a basket. Don't laugh! Milk crates are often easy to find and can be free if you look around hard enough. They're tough and are not affected by water or temperature extremes. They have wonderful handles that assist in moving your bike around.
Attach the milk crate to the rack using metal hose clamps. You might be tempted to use zip-ties. Zip-ties do work (for a while), but become brittle with age and will break at the worst possible time (when your crate is heavily loaded).

Putting your back-pack in your milk create is easy! Just throw it in! The high walls will make sure your bag stays in. If you're concerned about it falling out, use an old innertube tied between the handles on the side. (An old innertube makes a great tie-down for other things in your crate as well!)
Your bike is now much more useful. You can stop for a bag of groceries which fit nicely in the rack (and your back-pack can go on your back for that leg home from the store).
Do a google image search for "milk create bike" and you'll see some examples.


Rear derailer shifts fully only in middle of cassette and loses alignment with cogs over time I didn't even realise it, but I had been using the double shift Rapidfire feature on shimano's mtb sti's to move the chain only once up the cassette. Thats two clicks for one change. Its only when I got fed up with having to 'upshift' once to bring it to proper alignment with the desired gear, I decided to tinker.

That's when I spent about an hour trying to get it to shift properly with the barrel adjuster and it just wouldn't.

After thinking about it, it is clear that the right shifter only pulls enough cable on the smalest one or two cogs. I had naturally learnt to use two lever clicks.

Some things:
-I have got a new cable that I bent a few places when I installed it, and ok outers. As the upshifting is fine, im ruling that out.
-its all 7 speed, from experience right hand shifters always break down. Specifically, m095 xt sti, lx m560 rd, new hg41 cassette/chain. I have changed the rd with identical results.

Service the shifter or do I need to set the cable up in a specific order?

There's not much that could happen to cause the shifter to pull and hold an incorrect amount of cable when you click it.

A simple test to see what the shifter is doing is to loosen the cable anchor (or slacken the system by pulling a housing out of a stop), pull the housing away from the shifter, pull the exposed cable there gently taut with pliers, and shift back and fourth through the range. You'll be able to see if it's working normally, missing shifts, releasing too many steps at once, etc.

Once they're this old, Rapidfire/STI shifters are prone to issues with lubrication around the pawls getting gummed up, causing engagement problems. From your description it sounds like this may be what's going on. This is common and easy to fix with some cleaning and relubrication. However, it's also the primary mechanical problem with these shifters that's fixable at all. If there's a broken spring involved, which is also pretty common, there's not much you can do.

To service them, the important thing is to never under any circumstances take apart any part of the mechanism itself. Depending on the shifter, there are usually covers that can be removed or nudged aside to let you spray the guts and/or work the pawls around. The usually recommendation is to use a silicone spray lube because it won't degrade plastic. If possible I like to put a small dot of grease at the pawls, roughly emulating how they come new.


What is the science behind interval training? How did coaches/scientists come up with specific interval training programs like X sets of Y intervals at Z heart rate/power, lasting T seconds? How are these numbers produced? Are these trial and error, is there good science behind them?

There are a number of possibilities but I can't say definitively. I'd guess it's grown from one or a combination of the following, in no particular order:

i. Consideration of event demands.

Coaches often create intervals which replicate the demands of a rider's goal events. e.g. if you are racing an event with a lot of short climbs which are often attacked, then some hard efforts of around that duration might be worth considering. Or in the case of track racing, it might be a certain number of laps of the track, with sufficient recovery to go again. And of course if you are doing time trials, then efforts that replicate time trial pace and duration are common.

ii. Published studies involving interval training.

There have been over the years a number of published studies which involved various forms of interval training. Many of these have been shown to be physiologically beneficial in some ways, and so these may have formed the basis of many such interval workout designs (e.g. Tabata). As has been commented upon, whilst many such workouts have demonstrated benefit in laboratory study, they are by no means necessarily optimal for any given individual, or for the specific requirements of that rider.

I should add that many of the published studies referred to were not primarily about identifying whether or how much an interval session was beneficial but rather it may have been about answering a different question, such as identifying limits of human performance, or in research on physiological (e.g. hormonal, blood lactate, VO2 etc) or psychological responses to particular types of effort, or indeed simply as a way to test models of human performance, or to assess the validity of particular testing methodologies, or what happens when other factors are controlled (e.g. environmental conditions). Indeed many studies are not performed on trained cyclists but are primarily about assessing health impacts of such workouts on untrained individuals or for those with particular medical conditions. But along the way interval prescriptions and their impact were measured and noted.

iii. The terrain and riding environment people had available.

e.g. some people had a local climb which took about 5-minutes to climb, and so they ended up doing hill repeats of around 5-minutes. Or they had a section of flat road which enabled ~20-min of hard steady state effort before they had to stop for some reason (e.g. edge of town, traffic lights, end of road). Turn around and do it again and voila, 2x20-min intervals are born. Or they are time limited and/or on an indoor trainer and so they are looking for ways to make the session useful as well as sufficiently mentally stimulating. Lots of interval sets are designed to fit within a given time frame.

iv. Mental considerations

Riders need variable challenges in their training diet to keep it mentally stimulating, fun even. A way to reduce the drudge of banging out the same old miles every day. Intervals are perfect for this, while admittedly for others they'd rather scratch their eyeballs out. So coaches design training challenges as way to balance the psychological needs of a rider with their physiological development. Training needs to be sufficiently enjoyable, else you are less likely to do it.

v. A way to track improvement

When you do a set of intervals on a regular basis it makes for a good way to measure improvements in performance, and also when performance is no longer improving, it's also a sign a change in routine is perhaps warranted.

vi. Folklore. It worked for someone else, so why not try it on others?

A "what we always did" or "they did it and it worked" kind of approach. A mythical secret training sauce. Again by no means optimal nor necessarily specific to an individual's particular needs, but as I'll mention later, not always as bad as some might think. "We did these efforts and through trial and error discovered we needed 10 minutes recovery and could do 5-7 of them at most. And our riders were flying 5 weeks later."

vii. Understanding the key physiological capabilities, capacities and development needs of a given rider, and formulating training workouts that are specifically suitable for them.

This is where one forms a deeper understanding of what sort of training efforts are most suitable for a given individual's physiological development. This is in part informed as much by the published research as it is by measurement and monitoring of the specific responses an individual has to such training, especially via the use of a power meter.

There are only a handful of physiological capacities one needs to be concerned with and the balance of these attributes helps guide what sort of workouts are suitable.

The reality is that the impact of training at different intensities on stimulating beneficial changes to these various physiological attributes is on a continuum. What this means is that most intervals sets provide a development stimulus across the range of physiological capability. e.g. just because you are doing short hard intervals doesn't mean they won't also have an impact on longer range aerobic capabilities. It's really about targeting the primary adaptations you seek to improve while also recognising the impacts also spill over to other areas.

And this is why, despite some level of folklore and ad-hockery to how such things arose, the physiological responses to such efforts still, by and large, work.

Finally, while intervals typically are mostly about physiological development, there are of course other factors to consider when it comes to a rider's improvement: skills, mental approach, recovery, team work, strategy, tactics, and often interval training can also incorporate these elements (e.g. sprint training with a mate, team pursuit style efforts and so on).

There are thousands of published scientific studies involving various uses of high intensity interval training protocols. There are also many studies comparing HIIT with predominantly threshold level aerobic and/or steady state training.

Listed below are some studies comparing HIIT protocols. This is by no means an exhaustive list of references.

https://www.researchgate.net/profile/Paul_Laursen/publication/7665818_Influence_of_High-Intensity_Interval_Training_on_Adaptations_in_Well-Trained_Cyclists/links/5aebc78aa6fdcc8508b6e3dc/Influence-of-High-Intensity-Interval-Training-on-Adaptations-in-Well-Trained-Cyclists.pdf

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3737829/

https://www.ncbi.nlm.nih.gov/pubmed/24206175

https://www.ncbi.nlm.nih.gov/pubmed/22124355

https://onlinelibrary.wiley.com/doi/abs/10.1111/sms.12165

https://www.tandfonline.com/doi/abs/10.1080/17461391.2011.606844

https://journals.humankinetics.com/doi/abs/10.1123/ijspp.2012-0389

https://dev-journals2013.lww.com/acsm-msse/Fulltext/2007/09000/Nonconsecutive__versus_Consecutive_Day.00030.aspx

https://www.thieme-connect.com/products/ejournals/html/10.1055/s-0042-109539

http://www.ijpefs.com/index.php/ijpefs/article/download/76/67

http://researchrepository.murdoch.edu.au/id/eprint/17553/

https://scholarworks.umt.edu/etd/1136/

https://dspace.lboro.ac.uk/dspace-jspui/handle/2134/25496

http://open.uct.ac.za/handle/11427/15517

https://www.thieme-connect.com/products/ejournals/html/10.1055/a-0631-2682

https://www.nrcresearchpress.com/doi/abs/10.1139/apnm-2015-0238


Is it possible to install a gas engine kit on the bike's existing speeds? Such as with electric assistance.  I'd like to install a gasoline engine kit (because electric ones are wildly expensive) on my bicycle, without the sprocket:  I want to attach it to the existing gears, because I would then be able to shift through the gears to increase/decrease speed as I wouldn't with a 48-tooth/32-tooth sprocket.  I have not been able to find a kit that will place the chain on the right of the bike, where the gears are.  Is there a kit that can do this, or is there a way to fadangle a normal kit to run through the existing speeds?

Generally speaking, no.
A liquid-fuel engine wants to turn a lot faster than a cyclist would turn the cranks.  That's why a retrofit engine often has a small drive cog and an enormous cog on the rear wheel, to decrease the revs and increase the effective torque.
The optimal speed of a small capacity liquid engine is somewhere between 1000 and 2500 RPM.   A cyclist would do 60-90 RPM on the crank, with 120 being possible-but-abnormally high.
If you want a motor bike, its often cheaper to buy a 50cc motor bike and leave your normal bicycle unmolested for riding.
Also, if you remove the ability to pedal, then your ride becomes a motorbike no matter what displacement limits you're under.

Additionally - these liquid engines cannot generate enough torque to pull away from stopped.  So the rider has to pedal up to a minimim of 10-20 km/h and then can release the clutch.  Trying to start a small displacement motorbike from stopped is impossible without stalling.
You need the pedals working to get them moving.


What kinds of brake designs exist, and what are their general pros and cons? Here are the ones I'm aware of:

Center Pull Cantilever

Slightly better braking than side pull brakes.
No recentering problem.
Relatively rare

V-Brakes

Cheap to produce.
Similar in braking power to center pull brakes.
Relatively short service life before the resetting springs fail.

Cable Disk Brakes

Second best stopping power available.
Same kind of technology in automotive brakes, these work in wet or oily conditions.
Require stronger rims, forks, and tires to be used.
Relatively heavy.
Expensive.

Hydraulic Disk Brakes

Stronger braking than cable disks.
More complicated; more parts to break.
More expensive than cabled disk brakes.

Have I missed any pro or con, or any brake types here?

Here's a more complete list, arranged roughly in increasing TYPICAL stopping power, with pictures:

Rod

Largely outdated
Very low stopping power
Imprecise and heavy
For more information: http://www.bikejuju.com/2010/how-do-rod-brakes-work-a-visual-primer/

Coaster/Drum/Hub

Include 'Back-Pedal' Brake
Generally not very powerful
Very low heat produced for extended periods of braking, used in freight bicycles for example
Isolated from the external environment (rain, mud, etc.)
Very low maintenance
Braking force transferred through spokes like disc brakes (Can't use radial spoking)

Side Pull Caliper

One of the weaker brakes out there for Mountain/BMX use
Somewhat common on older cheap bikes
Note the single pivot point
Sometimes used on road
Light weight
Cheap
Simple

Dual-Pivot Side-Pull Caliper

Common on road bikes
Easily centered so they don't drag against the rim
Note the second pivot point on the right arm
Light weight
Aerodynamic
Slightly more powerful than the cheaper calliper brakes

Center-Pull Caliper

Somewhat common on road bikes
Light weight
Protrude less from frame/fork
Pose a cable pull design challenge for suspension designs (both front and rear)

Center-Pull Cantilever

Better braking power than calliper brakes
Require Cantilever/V-Brake mounts on fork/frame (below rim)
Inexpensive
Protrude from frame/fork very extensively, so not used much in BMX / Trials bikes
Pose a cable pull design challenge for suspension designs (both front and rear)
Center better than Caliper brakes

Delta Brakes

Found on some older road bikes, now uncommon
Aerodynamic
While they look like center pull calipers, they have a few mechanical linkages internally that change mechanical advantage and other qualities
Heavy
Variable Mechanical Advantage (not desirable)

Side Pull U-Brakes

Common on some BMX Bikes, older mountain bikes
Common for trick bikes that route the front brake cable through the steerer tube
Require U-Brake mounts on fork/frame (above rim)
Somewhere between caliper and V-Brakes for stopping power*
Very little protrusion from the sides, so very little to catch your leg/pants on

Center/Dual Pull U-Brakes

Common on some BMX Bikes, older mountain bikes
Require U-Brake mounts on fork/frame (above rim)
Even less protrusion than side pulls
Again, between caliper and V-Brakes for stopping power*

Note on U-Brake power: I have a type of center pull U-Brake that uses a wedge that forces the pads into the rim and stops with more force than any V-Brake I've ever used, and has crushed rims for me. The TYPICAL U-Brake design would be between TYPICAL caliper and TYPICAL V-Brakes.

Roller Cam Brakes

Shown here on U-Brake Mounts
Smooth feel
Somewhat rare

Direct-Pull Cantilever Brakes / "V-Brakes"

Most common brake for Mountain bike use
Require Cantilever/V-brake mounts on fork/frame (below rim)
Generally more powerful than non-disc brakes due to the mechanical advantage
Require different levers than the other rim brakes (the levers pull more cable and have less mechanical advantage than the others)

Hydraulic Cantilever Brakes

Relatively New
Increased stopping power over non-hydraulic cantilevers, but lighter and more aerodynamic than disc brakes

Cable Disc Brakes

Don't heat the rim or use it as a braking surface
Will run fine on bent/cracked rims
Aren't as affected by mud/water as rim brakes
Increase load on hub/spokes/rim eyelets because the braking force is transferred through them. Shouldn't use Radial spoking with them.
All this is true of other hub/coaster/drum brakes as well.

Hydraulic Disc Brakes

Same as cable disk, but...
Stronger braking than cable disks.
Better feel / less input force
More expensive

Hydraulic Rim Brakes

Common on rear brake of trials bikes and somewhat in Europe, also used extensively for unicycles.
Most stopping power of any brake type
Provide the most 'lockout' - a stiffened disc brake will still allow flex from the hub and spokes, where this will not
Can easily crush most single walled rims


Are drop bars suitable for winter commuting? I've been told by somewhat knowledgable people that drop bars aren't suitable for winter cycling in snow and ice. Is there any validity to this? If so, why, and which style of handle bar would be preferable?

Drop bars in of themselves are fine for winter riding. However, there are some peripheral issues involved. Your average flat bars will offer a bit more control in slippery conditions because flat bars are much, much wider than drop bars. A bike equipped with drop bars may not be the best bike for winter riding. But properly configured and sized drops can be excellent for winter riding.

Handlebar Width: Drop bars tend to be narrower than flat bars. You can mitigate this by getting wider drop bars; the ones meant for touring are great for winter riding.

Keep in mind that handlebar sizing isn't an exact science, but you generally want them to be as wide as your shoulders. A lot of road bikes won't have anything approaching this kind of width. (Also, there aren't that many wide, stocky roadies.)

Tires: Road bikes--which is where you usually see drop bars--often won't allow for the fitting of appropriate tires for riding on snow and ice. Not the fault of the drop bars!


Aero bars are a pain in the neck - are there strengthening exercises? I've got a set of aero bars on my tourer, and now I've got the hang of them I rather like them, especially when solo and into headwinds or trying to put some distance behind me on a long straight.

A couple of weeks ago I did a rather long ride with a gentle headwind on a fast road at the beginning, so started out by using them rather a lot, and I made good use of them later too. By a rough estimate I used then for over 100km in a day, likely much more. But for a few days afterwards I had real neck ache (DOMS) in the muscles that hold my head up - I'm only a touch lower than in the drops but it seems to make a difference (my bars aren't that low to start with - the forearm pads are ~7 cm below the saddle and they don't stand very high above the handlebar).  Yesterday's shorter but still respectable ride wasn't conducive to so much continuous use, but I could still feel those muscles getting tired - no aches today though.

While I try to get some use out of them as often as possible, I'm not happy on them in a group, and my longest regular solo ride is only 30km. So are there strengthening exercises that can be done off the bike? Perhaps something from the long time trial people.

There are a number of things you can try.

Firstly the aero position on the bike and holding that position is often related to how flexible your hips and lower back are as well as the strength of your core, so yoga, stretches of those areas, and core exercises will make it easier to hold an aero position in turn taking strain off your neck.

There are some neck specific exercises that will improve neck strength specifically those similar to what f1 drivers use to handle the G forces through fast corners.

Take an exercise band and tie the two ends to a pole or bar at height so that if you were sat down it would be at approximately head height. This will essentially give you a loop. Sit down at distance away such that when you put the exercise band on to your forehead it is tight and offering resistance.

You can then pull your forehead forward to engage the muscles. There's a link to video if my description is terrible.


Uphill riding hard for me New to riding what is the best way to ride going uphill? I live on a hill going down is fine but I have a hill to get to the main road.

Basically the only real way to get better at going up hills is to get fitter - which you can do by repeatedly riding the hill :-)

Some tips:

Stay sitting down
Use low gears and a fairly high pedaling cadence
Use good gear management, shift down progressively as you start the hill and keep pedaling cadence up.

The main point is you want to avoid using your anaerobic system and exhaust your legs. Pedaling too slowly and too hard will make you go anaerobic. Low gears and faster pedaling will keep you aerobic longer.


How might I measure the proportion of a ride spent in various hand positions, or has it been studied? This is something I've been pondering for a while, but a recent question How much faster when using drops and particularly Weiwen Ng's answer prompted me to give it more thought.
It's often said that most of the time on a drop bar bike is spent on the hoods, and that feels plausible, but I know with sustained headwinds I've ridden a long way in the drops (and much of the rest on the tops for a stretch on the rare sections out of the wind).  To plug in to calculators, and for curiosity, how might I measure the proportion of a (long) ride spent in various positions?  I'd assume a solo ride, so any solution would need to be mounted on the bike and not affect riding (too much) though a difference between solo and group rides would be particularly interesting and may explain some comfort issues.  Alternatively published data would be of interest, though very limited interest if it relates to pro races.

The cheap solution would be to obtain a bunch of stopwatches. Label one for tops, one for hoods, one for drops, etc. When you switch hand positions, stop the current stopwatch and start the applicable next one.


What is the regular maintenance on electric hubmotors? I don't own a Blix bike/electric bike though I rode one once... I was wondering where are the technical docs/howtos on the rear motor's maintenance?

I have to rework the back wheel, replace axle or cones or bearings and stuff once a year - or have bike shop/hobby shop do it, maybe because mine is cheaper Fuji bike, or maybe because I often hold a few pounds of stuff in the back rack, go on somewhat rougher bike paths and occasiionally hop off a 3 or 4 inch sidewalk edge.

This got me curious, what is the usual cone/bearing/axle replacement if a back wheel has a hub motor in it?

I found no manufacturer supplied technical docs / how-to on bicycle hub motor (or mid-drive motor) maintenance. There is a variety of rider created how-to information. Here is a link to the Electric Bike forum as an example.

Quick explanations of electric bike motors:

There are three configurations for electric bikes. Two different types of hub motors and the mid-drive motor.

Geared hub motors - this hub has an internal gearing system = greater complexity, lower durability.
Direct Drive hub motors - no gears, just an electric motor = simpler
The linked article also talks about the good and bad of each type of drive, but it does not go into depth on durability and repair.
Mid-drive - connects to a bicycle drive train = harder to install than either hub motor.

According to this thread in the Electric Bike Review forum the answer on hub motor durability and maintenance is - it depends.

Durability depends on:

The quality of the hub (if you can't find parts for the hub avoid it or be ready to replace it when/if it breaks)
The type of riding you do (hills generate heat in an electric system which can reduce durability)
The conditions you ride in, wet, dusty, hot, etc.

In this conversation on reliability in the Electric Bike Review durability on hub motor testimonies go from as little as 2,000 to as much as 20,000 miles.

The consensus is that a direct drive hub has greater durability than the gear hub. The wear items in the direct drive hub are the sealed cassette bearings. Replacing would be a matter of removing the old bearing(s) and installing new. The wear item in the geared hub are the bearings and the gears.

Here is a site with a variety of direct drive motor parts - not as an endorsement of any kind but only for part cost reference.

Other things that can fail on a hub motor, or mid-drive system:

Battery
Controller
Phase wires - if the motor gets too hot
Hall-effect sensors - track the motor's position

A mid-drive motor installs replaces the crank spindle or bolts to the down tube.
Going with a mid-drive system uses standard bicycle drive train parts. This type of system can increase wear on the standard drive train parts.

To get something you can repair make sure you can find 1. Replacement parts 2. Online repair help or how to video, before you buy. To some extent, when it comes to durability electric bike owners are blazing a trail - they don't have the history of the conventional bike.


How to board a ski chairlift that is not intended for bicycles? As the end of the ski season is approaching, I am thinking about visiting our ski resort by bicycle. I would like to do it at the end of the season to avoid the inconvenience of the crowd, and minimize the inconvenience I would make for others.

In the ski resort we have, it is pretty unusual to have bicycles. The chairs don't have any hooks or other appliances to hold bicycles, and the crew might not be able (or willing) to help.

In these circumstances, how can I ensure safe and smooth boarding and disembarking? I will be in a small group (2-4 people), all of us having standard (non-fat) mountain-bikes. I am willing to do basic disassembly (e.g. remove wheels) if it would help.

Our ski-lifts have standard chairs, designed for 2 persons (like in this example picture); they are not of the type that slows down when in the boarding/disembarking area.

Back in college, I did some downhilll racing at a ski resort with chairs like the ones you're talking about.

One guy carried his bike like this:

It had the advantage that when he dismounted, he just set the rear wheel down while still sitting in the chair, stood up, and walked off the lift with the bike next to him. The disadvantage was that it was an awkward ride to the top. If I remember correctly, it was also a little awkward to get onto the lift. He just sort of muscled it all into place.

Unfortunately, I don't have a picture but most of us did it differently. We would straddle our bikes just like we were about to mount them while waiting for the lift. When the ski lift came up behind us, we would pick our bikes up and set the handlebars across our laps with the frame between our legs. As we got lifted up, the bikes would just dangle below the lift chair. Then, to dismount, we would just set the rear wheel down, stand up straddling the bike like when we got on the lift, and take a couple of awkward steps forward, just like you might do if you stop a little short at a stop light or something.

This way had the advantage of being super easy to get yourself and the bike onto the lift, as well as being easy to hang onto your bike on the way up. You could also fit two people on the chair at the same time. On the flip side, it was awkward to get off the lift, but dismounting never felt dangerous at all.

Honestly, the ride to the top was super scary (for me, at least). As you can see from the picture, there's no safety bar on those lifts. You could feel the weight of the bike causing the chair to lean forward a bit. I preferred to lift my bike a little higher than everyone else and rest the seat on the edge of the chair between my legs. This allowed me to pull the handlebars back closer to my face, balancing the whole chair out a bit. It was a little awkward to hold the bike like that, but the lift chair felt more stable. It clearly wasn't necessary since no one else did it and no one fell off the lift, but it made me feel better.


How long will this alum frame last? I picked up this very cool 96-97 GT rage from Craigslist with the intention of restoration- a few rusty pinch bolts, spider eggs in the brake hoods, grinding bearings and pitted races, and all the good stuff that comes to a bike living outside for 5 years.

I was excited to get my first aluminum frame for the project as I knew it wouldn't be rusted like steel would have. (It spent a lot of time in the rain.) It wasn't for another day until I found hairline cracks forming under the seat post clamp and around the GT rear stamp. I suspect the clamp was over tightened at one point, but it was very normal when I got to it and the little slit cut into the back of the tube isn't squished or malformed which I've seen happen on steel frames that were over tightened.

How long will the frame actually last? It's a GT so it's got the triple triangle so I'm not worried about my seat stays coming loose or my seat post falling into the tube. Should I be? I know fatigue cracks in some places means it's time to trash the frame, but I'm not a pro racer and I ride pretty lightly. I'm interested in other people's experiences with aging aluminim and possibly hearing thoughts aside from putting it on the curb for trash day.

I can feel the cracks with my fingernail but they're too small to actually fit my nail inside.

I've read 7005 aluminim cannot be repaired since it requires heat treatment. I love this bike because I love 90s and GT (and its so hard to find tall frames that aren't 70s gas pipe builds)
but I'm not sure it's worth being a money pit. Are there other repair options? Does drilling cracks actually work? Can I permanently install the seat tube?

A crack developing there, is most likely too much seat post out of the frame, or in actual fact, not enough seat post being in the frame.

The biggest problem with a crack in this location, is that it then causes most force to be placed on the join between the top tube and seat tube. You also have to think about what would happen if the frame were to suffer a critical failure in this position - it will most likely be landing from a drop or, more likely, while sitting and hitting a hole/bump; neither great options and the more likely of the two being much more painful!

Drilling a crack is to minimise crack propagation. And there are few repair options with this style of frame (for sensible money).

This can be welded, but you would risk this just getting worse. If I remember correctly 7005 using artificial ageing rather than a traditional heat treatment - a filler material could be used between the post and frame to bond them and strengthen the seat post. The sensible money "option" if you really want to keep the frame is to get a very long seat post (ensure that there is a lot in the frame, around 20cm+) and keep checking for further crack propagation. The best thing to do here would be to contact a specialist aluminium frame builder and ask their opinion.

To answer the question in the title - aluminium work hardens quicker than other materials, and tends to crack due to fatigue much quicker than say carbon, steel or titanium.

Unfortunately I think it could be time to consider a new frame.


My rear wheel is bent. How do I know which replacement rim would work? I have a 2015 Diamondback Insight 1. (http://dbcorp.diamondback.com/insight-1) The rear wheel is bent and I think needs replacement. The bike specs say that it's a "32h Equation R23 Doublewall" but I haven't been able to find a replacement. Which do you think would work for my bike?

Thanks so much!

That link appears to be a dealer-only one, I get a login prompt. It's a flat bar road bike and based on a google search comes with 700c/ISO622 wheels and a 7 speed cassette (7 gears on the right hand shifter). The R23 in the name very probably means the original rim is 23mm wide.

That means any 7 speed narrow rim 700c wheel should work.


Android/EVO bike mount recommendations Does anyone have experience mounting an EVO phone on the handlebars of a road bike?

You could always try making your own. There are lots of different ideas for designs over at Instructables the one below uses the bracket off an old reflector plus a phone holder (ie for mounting your phone on a car dashboard) screwed to it. More details here. I particularly like the rubber bands for extra security. My main worry would be the rain though and the danger of getting the phone wet (but then I do live near Manchester in the UK).


problem in gear shifting I'm using a  21 speed bicycle,the problem is I'm unable to shift the chain to the smallest derailleur(rear)...the shifters are thumb press type
there's no problem in pressing the shifter...when shifting to the toughest gear the chain shifts up to second smallest derailleur(rear)..when i press the shifter it's moving but the chain is unable to catch the smallest one...can't figure out the problem :(

It sounds like you need to adjust your rear derailleur - the cable may have slipped a bit and have insufficient cable tension, or if you recently had a crash, you may have bent your derailleur.

I'd recommend reading this to learn how to adjust your derailleur.


Flat tire: white liquid inside the tube I got a flat tire, kind of a big hole in the inner tube. It was raining a lot so I walked home through the rain and water puddles, and everything got wet.

Now I want to patch the inner tube, but when I inflate the tube, some kind of whiteish liquid is coming out of the hole. I don't know if it is water that got inside (it's not that much anyway).

Do I have to wait until everything dries inside the inner tube (could take a long time) or is this is some kind of lube that comes inside it? If so, is it fair to say I don't have to worry and I can apply the patch with no problem?

There is a type of whitish liquid sealant that some folks (shops, manufacturers) put inside tubes, so that if you have a small puncture it is autimatically sealed by the liquid, which solidifies around the tiny puncture.

From what you say, it is not possible to say if that is the case, or if the puncture is larger and water went inside the tube. That would theoretically allow for the powder inside the tube to form a gooish liquid, although I doubt there would be enough amount of water for it to be noticeable.

From my experience, patch glue doesn't mix well with these white sealants, in every tube I patched that already had this liquid the patch got loose soon after, resulting in another flat. So I gave up these sealants forever, unless something new and different appears.

I would suggest, in this case of doubt, that you use the tube's rubber for another stuff (tying something at home ;oP ) and buy a new tube. That is not so expensive, and buyng new tubes is integral part of cycling, anyway. Besides, you could cut the old tube to look inside it and get more info which could save you future trouble (Where did this tube come from? Would other new tubes contain the same liquid? Was it sealant or just water? Etc.)

Saving old ones for "reuse" too, they are much more useful in the basement than in the landfill.


Selecting a compatible BB: spindle offset Replaced Shimano Bottom Bracket, now front derailleur won't shift to largest gear
How do I measure a bottom bracket?
I thought the only thing that mattered when replacing a bottom bracket was the thread size (68mm) and the spindle length. - unsavory

Me too. I had thought that the things to consider are:

Thread specification e.g BC 1.37 x 24, English or Italian
Thread width: 68 or 73mm
Cranks interface
Spindle length e.g. 113mm

And now it turns out the axis offset matters. How do I determine this before purchase. E.g. in this datasheet there is no mention if the axis is symmetrical or offset.
When should I be worried about unsymmetrical BB spindles and where should I check to ensure compatibility?

With Shimano there are "E" and "K" variations of bottom brackets that refer to coaxial mounted front derailleurs and chain guards respectively. The BB variations provide for enough space on the drive side spindle to build in another "ring" of the derailleur or the chainguard carrier.

For exact paramenters Sheldon Brown could be helpful too.
http://sheldonbrown.com/bbdrop.html


Proper Posture for Preventing Painful Posteriors on Penny-farthings? After riding relatively short distances (about five kilometers), I’ve developed a literal pain in the rear. I suspect the hard seat is the primary culprit, and I’m sure I’ll be able to replace with something more sensible. That’s a no-brainer.

Is there a proper posture to help alleviate or minimize the bumpiness inherent in the system? I’m concerned that this may evolve into an affliction of the lower back. That would be unfortunate as I’m enjoying the ride and from up on high, but not the consequences down low.

Penny-farthings are known for their relatively harsh ride, and lack of stability. There is no option on many frames to replace the saddle, although there were some that you could. I would get a sprung Brooks saddle, or similar, which might add a bit of comfort without significantly sacrificing the vintage look.

It will add a bit of suspension effect as well.

Something like this:


Will slightly slimmer seatpost make a difference? I have an old Peugout bike that needs a 23.8 (to the best of my measuring abilities) seat post. I can't find such a seatpost in all the obvious shopping places, but I did find a 23.4mm one. I'm just wondering if I should give it a try, but since it's £20 I wanted to ask if anyone had experience with such fitting.

According to Sheldon Brown's site, there are 1987 Peugot Versailles with 23.8mm seatposts (and I have heard of other french bikes with 23.8 mm seatposts, so it is probable that you've measured correctly). The measurement should be done with calipers or a seat post measuring tool, though.

One solution I've heard of is buying a 24 mm seatpost and sanding it down until you shave off 0.1 mm. Another is starting with a smaller seatpost (bmx for ex.) and trying to shim it in somehow (coke can or whatever). Of course this is all ymmv, but its quite difficult to find 23.8 mm seatposts.

I'd probably just get the 23.4 mm one and hope for the best.


Relationship between chain tension and chain wear On a 10 speed road bike, what is the ideal chain tension?

I was recently told (by a bike shop) that my rear derailleur should be fully extended (pointing forward) when the chain is between the 2 biggest cogs.

Does a riding with high tension decrease your chain life quicker? It seems logical that it would, so perhaps I was given bad advice.

The chain should be as short as possible and as long as necessary. It will usually shift better with proper tension. The tension shouldn’t affect chain life though the shorter chain will. Make a 104 link chain shorter by 2 links and it has almost 2% less material and thus shorter life. But that’s really a small effect.

I can dimly remember an article which stated that higher tension (they tested big chainring vs. small chainring) is actually more efficient, probably because there are less vibrations.


Is riding shirtless safe? During the summer, I like to go for rides on trails without a shirt. Is this safe?

Also, related: is it rude to other people on the trail not to wear a shirt?

Safe is a relative term in this instance. A shirt might protect you in a fall, but only just. You'll know immediately whether a shirt can protect your skin from sticks, branches, and prickers dangling into the trail. If you were going fast enough flying insects may even make an impact, though I can't imagine it'd be terribly painful.

Shirts do offer some protection from two things: sunburns (and subsequent skin cancer) and bites from insects (potentially carrying disease.) For lightly complexioned people, skin cancer is a huge danger and can develop even without having been sunburned. Insect-borne diseases are also a big deal in most places. Having been treated for Lyme disease, I can attest to the importance of wearing insect repellent and, yes, shirts.

Additionally, that thin layer of material actually keeps you cooler by blocking the sun from reaching your skin - this is the same reason why desert dwelling peoples wear lightweight material all over their bodies. Having a shirt on also keeps you from sweating all over your bike and other gear.

In terms of etiquette: if you're out in the woods and there aren't many people around, go for it. If you're bumping elbows with people on a multi-use trail, maybe consider some modesty.


Is it safe to use aluminium seatpost adapter (27.2mm to 31.6mm) for a carbon frame? I have Cane Creek Thudbuster Seastpost (aluminium) 27.2mm x 400mm which i want to use for a bike with a carbon frame (31.6mm seat-tube).

I'm thinking about getting a seatpost adapter/shim from 27.2mm to 31.6mm, but I'm not sure if that's not going to damage the carbon frame. Shim itself is ~80mm in length.

Is it safe to use?

80 mm length should be long enough to provide stable and good grip. Do make sure to use carbon mounting paste, of course, wiping any traces of grease (if they exist) off the adapter and the seatpost. If the seatpost stick long above the frame and if it's an off road bike, I might consider it a tad bit risky move. Otherwise, you should be fine.

And, like the previous poster said, to occasionally check for traces of galvanic corrosion. You don't want the seatpost stuck to the frame.


Front Shifter Won't Shift into 3rd The front shifter is a Shimano integrated brake-and-shift assembly. The front derailleur "groupo" is Shimano SIS. I can pull the cable to make the derailleur shift into third but the shifter doesn't have "enough throw" to do it via the shifter.

Pulled the cover off and threw some lube in it and it appeared to look just fine, but didn't take the closest of looks before having to shutter the shop.

First and second work just fine. Shifts up, shifts down.

Any ideas?

Thanks in advance.

Cable tension

Limit Screws

Derailleur position/angle

These are the only things that actually affect your shifting mechanically.  If those are all proper, something is broken/misaligned/shredded.


Can i fit a 26 x 1.5 tyre to my wheel? I have a Hybrid bike that has 26 x 1.95 tyres fitted, they are knobbly's and I want to change them for road tyres, I have seen a make that I like but it is a 26 x 1.5 Will i be able to fit them to my bike.
Thank You

According to my handy-dandy tire/wheel compatibility chart, if your rim is between 17-24.9mm Inside Rim Width, that tire should work fine with your wheel.


Crankset arms length and chainring for 5 year-old My five years old little girl rides a BMX micro mini bike with 18 x 1" wheels. The original bike came with 130 mm crankset length, 38 tooth chainring and 14 tooth rear cog.

However, looking at her on her trainings, came to my attention the way she was pedaling. After reading a lot in the web I found out that there are shorter  crankset for small rider. Due to the fact that I can´f afford $150 US dollars crankset plus shipping to my country, $70 US plus customs fee. I decided to cut and shorter a 175 mm crankset arms to 110 mm, and I did a great job.

So, due to your expertise and knowledge, I would like to ask you which chainring and cog could you recommend for my daughter.

Gearing is a very subjective question.

Using Sheldon Brown's Gain Ratio Calculations, 36:17 on 110mm cranks will give a 1.25% lower gain ratio than 38:35 on 130mm cranks.


Bike Fit for 5'3" (1.60m) woman, 47 or 51 cm? My issue is that I have a 51 cm Cervelo, but the reach is too far. I've tried changing out handlebar stem to shorter/angeled, spacers and smaller handlebars. That helped some, but still a little too far reach for comfortable longer rides. I want to get a 47 cm frame with same changes I made for the 51 in order to have less reach, but the bike shop says that the reach will only be one cm shorter, and the handlebars will be two cm down. So effectively the reach will actually be more. That doesn't make sense? And the bike shop does not have any 47 cm bikes in shop.

The bike shop is correct. This will depend on what model of Cervelo you have but looking at the Classic Road geometry here,

48cm: stack 505mm, reach 560mm

52cm: stack 530mm, reach 569mm

That's annoying but kind-of does make sense. At the small size extreme of frame geometry it's hard to reduce the length of the bike and leave enough space between the wheels, because the wheels are the same diameter as larger frame sizes. This is why some small frame road bikes are built around 584mm (650b) wheels instead of 622mm (700c) wheels.

It's possible that 0.9cm reduction in reach is enough, and you can raise the bars up a couple of cm with a different stem.

If you are thinking about buying a whole new frame and transferring wheels and components over, you should probably think about a whole new bike of a different model/brand that fits you better. If you sell your current Cervelo the overall cost may be comparable to buying a frame.


Looking for advice - cracked rear hub along bearing races - How to buy a new rear wheel? TL;DR below

My bicycle is an old used Trek hybrid (1994?) that I got a few years back. When replacing the tires recently I discovered that my rear axle was significantly bent (not surprising for a freewheel bicycle), and upon removing the axle and bearings I discovered massive cracks all along the freewheel side of the rear hub. (see photos below)

I'm sure that the hub is toast - but where do I go from here? I could buy a hub and rebuild the wheel, but I am guessing that is a waste of money compared to a new wheel.

Where/how do I look for a replacement rear wheel? Rear dropout spacing seems to be about 138mm, rims are 700c and about 26mm wide. I have a 7-speed freewheel that seems fine, but I am wondering if it makes sense to just get a freehub and a new 7-speed cassette to avoid future bent axles. Currently have all Shimano drivetrain components, not sure what model.

I mostly do road riding and commuting, with occasional light gravel. Brakes are rim cantilever style.

imgur photo album

Thanks so much for the help!

TL;DR: Rear hub cracked - new wheel? How much, where to look?

The bearing cup is toast from being ridden with a bent axle. The hub shell does not appear to have structural cracks.

With a new axle you could potentially get some life out of it, but you're probably on the right track with replacement, especially if this is a bike you're riding indefinitely.

With either the freewheel or cassette route, the sort of wheel you'd need are very common repair items that are easy to get from a shop or internet retailer. You need any rim brake 135mm 700c hybrid freewheel rear wheel, or any rim brake 135mm 700c hybrid cassette rear wheel plus a new 7 speed cassette and a 4.5mm cassette spacer.

Replacement hybrid wheels with 7-speed freehubs used to be commonplace and are a little technically superior when applicable due to their wider flange spacing, but aren't made by any large wheel producers I've seen in recent years, in part because those bikes are aging and in part because of the explosion in repair wheel compatibility permutations shops and wheel producers have had to deal with in the last decade. Hence running an 8/9/10 with a spacer has become the norm for replacements.

Given it's bent axle problems that got you here, there's a case to be made for switching to cassette. In almost all cases it makes sense to start out a new chain at the same time, and the potential gotcha then becomes the wear state of your chainrings.