Chain "Stretch" [courtesy of sheldonbrown.com]

Cyclists often speak of chain "stretch", as if the side plates of an old chain were pulled out of shape by the repeated stresses of pedaling. This is not actually how chains elongate. The major cause of chain "stretch" is wearing away of the metal where the rivet rotates inside of the bushing (or the "bushing" part of the inside plate) as the chain links flex and straighten as the chain goes onto and off of the sprockets. If you take apart an old, worn out chain, you can easily see the little notches worn into the sides of the rivets by the inside edges of the bushings.

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To prevent chain 'stretch' one needs to take certain simple considerations:
1. Do not over tension your chain. I understand that it's important to prevent chain drop but having your chain too tight will drastically increase chain wear.
2. Clean and relubricate chains often, consider appropriate lubrications for given weather conditions (wet lub for wet weather, wax for snow, dry teflon for dry weather). Dirty chains hold onto dirt and road grime which helps to eat away at the chain's rollers.
3. Straighten your chainline. A crooked chainline wears a chain in much the same way that cross-chaining on your geared bike.

I've still yet to see a customer actually break a chain. If it happens, I imagine they happen under very extreme conditions (world class sprints doing jumps on 90inch+ gearings). Cleaning your chain and running a little slack not only improves your chain's life and performance, it also helps prevent cog and chainring wear.

That chain is for grinding on a BMX bike. Its totally pointless on any other bike.

hello, this post may be very old. i am too lazy to read through the 3rd page.

i have broken 3, yes THREE KMC chains. one was on my old IRO track set up, other two were on my tsunami track set up. both set ups were track frames, with track wheelsets, the spindle length was correct, the 1st crank was an IRO, crank on tsunami is sugino 75 with zen ring. the chainline was perfect. these chains were all broken running 47x14, sometimes 47x15 in hilly syracuse, ny. where i've been for the last few years. i am moving back to manhattan and don't want to eat **** after a link fails and wraps around and locks the rear wheel. anyone who has brooken a chain while starting a sprint up hill knows that it's pretty scary with traffic around. and it sucks when the chain goes through your spokes and a chainstay, so that you bend a few spokes in addition to twisting the chain.

i'll admit, in one case i forgot i had a half link on there which is most likely the reason it failed, but in the other two cases, i had a straight chainline and good tension and well cared for, lubed and cleaned frequently. all links were smooth (i know how to use a chain tool). in all cases i was not using a master link. maybe it was the salt they throw down after a snowfall, although i dunno if those chains contain any allu. does salt **** steel? i ride brakeless and have been for many year

i might just make a new post, but is there anyone on here that has broken multiple KMC or similar average grade chains, has upgraded to something absurd like the super toughness or DID and noticed a significant difference? once you get going any chain will do just fine. but it is the stops and starts that have ***** my kmc's. should i buy the $60 toughness or just buy a new KMC every 4months?

f-ucking fixed gear. this s-hits a ****-ing disease. mother f-uckers

What model KMC chains? They do make some light duty models. It's 510 or nothing when it comes to KMC.

http://www.bikeguide.org/guides/drive/kmc.php

What breaks chains is cross gearing not the granny. A 24t ring allows you in theory to apply twice the force on the chain but in practice it just doesn't happen. You can't apply half the force to the pedals with a granny on trails as you can with a normal road gear during a standing start.

Holy **** cat 2/3 roadies. Get the **** over yourself not that strong. Noone stretches chains in a few rides it just not possible. If you're breaking chains on the road it's cause you didn't install them right.

wow.
 

I don't know who "Noone" is but good for him (or her). Read the original post PECKER! I never said I broke or stretched a road chain. Thanks for the useless input. YOU ARE COOL.

PF

I'm going to break this down for you really simply

You got useful input on the first page.

1. If you break a lot of chains on a ss mtb it's your fault not the chains'.
2. You aren't strong enough to stretch chains quickly. Strength plays only a minor roll in chain stretch.

You then continued to argue that you were "really strong" and tried to impress your strength on us by saying you're not just riding around the city you're going to be on fast road rides holding on with the 2/3s. You continued to insist you don't need something that's going to stretch out after a couple of hard rides.

1. 2/3 roadies aren't usually that strong and you probably aren't either.
2. NO ****ING CHAIN IS GOING TO STRETCH OUT AFTER A FEW RIDES unless perhaps those rides are 1000k brevets or something.
3. Riding around the city is probably more likely to break a chain than a fast group ride. Standing starts are where the most force is applied to the chain not constant speeds in the high twenties or jumping from 28-38. Not to mention skidding to a stop which if you're doing on fast club/group rides is going to make you very unpopular.

Don't be an ass:
1. Don't assume you are stronger than the people giving you advice unless you have strong evidence to back it up. Winning chariot races against 2/3 track sprinters would qualify.... hanging with 2/3 roadies on a group ride doesn't.
2. Pointing out non-humorous spelling/grammar errors on a message board is only one step above threatening to quit.

i lol'd

I think we're in agreement that what breaks chains is not the strength of the rider. Except maybe in the case of our OP here with his massive guads. Next he'll be telling us he dials it up to 400 watts. (roadie forum humor, sorry)



OP, I suspect your chainline is a bit off. Either that, or the link isn't put together correctly. You aren't using some sort of quicklink/Masterlink are you? Some people like to take their chains off a lot and use these links but if not done correctly, they fail quickly. A lot of roadies have had this problem; chain breaks with little usage.

ok.
 

I apologize for engaging in this back and forth internet banter with you. NO GOOD WILL COME OF IT. I assure everyone that my intent was to gain knowledge and not to brag about how tough or strong that I may or may not be. I truly appreciate everyone who gave an honest and genuine answer to my initial and secondary post on this thread. To me these forums are an excellent way to gain valuable information about the sport that so love. I just don't understand the "I know it all; you are basically a liar and an idiot" replies. What is the purpose?

Take Care,

PF

No it doesn't or at least it shouldn't(sheldon made a fair number of claims that are quite questionable). What breaks mtb chains is being cross geared with a triple and a 24.

In the 36x18 the 36 allows the rider to put more force on the chain.
As the size of the rear cog goes up however the rider does so less and less frequently. A 36 only allows for 33% more force than a 48. That it is not enough to break chains. The low gearing further limits this especially off road.

If you come here for valuable information than don't argue when everyone tells you that the premise of your question is wrong. If you insist on doing so don't be surprised when people question your motives as they try to make clear that you quite frankly idiotic though probably not dishonest arguments are strongly opposed before they confuse others.

Whatever you say Sport.

Oh yeah, I agree that a 36x18 would probably not generate enough force to break a chain. My point was that as the gearing goes down, the amount of torque on the drive train goes up, which makes it more likely to break a chain.

Although you're right, cross chaining probably has a lot to do with it.

It takes a more sophisticated view of it though to understand what breaks a chain though. One must understand the How much force is applied to what and how much torque is applied to what parts of the drive train as well as how conditions limit the maximum force the rider can apply to the pedals or the ground to the tires. It is true that a lower gear allows a rider to put more torque on the rear wheel but that is meaningless in terms of the chain.

I've broken 3 "Z" chains. Replaced my chain tool (backing plate wasn't butting up against link) and haven't had a problem since.

Even riding brakeless, you are going to put much less stress on your chain than say a MTB running uphill in low gear.

too bad that HKK (made in Japan) has recently made the executive decision to deprive the world of their high quality chains and only market their products to ONLY Japanese suppliers.

enjoy the sweetness while you can!

yes, typically salt (NaCl) does hasten the oxidation of steel and most other metals for that fact (even aluminum)

IZUMI V Super Toughness

I believe this thread was originally made to find a "strong chain" so here is my rational.

1- umm when talking about something as simplistic and available as a chain, there isn't much inflation factored into the cost, so in most cases your paying for what you get.

2-if you ride a fixed gear/ track bike, why would you wanna skimp out on a part that replaces both your brakes and almost whole drivetrain system. If you factor in all that, a $60 chain is a bargain.

3- even though most chains on fixed gear bicycles move in a (almost perfect) linear fashion. Fixed gear cyclist put chains through the most brutal treatment in the sense of drive train duties.

the line up for "strong chains" is as followed...

Izumi V Super Toughness- NJS certified... need i say more?

Izumi ESH - V Super T, without the NJS stamp

Wippermann Super Duty - just ridiculous, Invented by the paranoid, inspired by German tank chains.

My local bike shop is was started by some famous cyclist dude, who's son, an ex track bike "star" (who now runs it) stocks both the KMCs and the Izumi Super Toughness. When I needed a new chain I went in and asked his opinion. He told me the people in the Olympics were using Izumi's, but didn't think I'd need one. He assured me the KCM 710 I got was a proper "track chain". I've been using it heavily for months and I can't complain about it.

But then again, this might be a bit loopy. He installed my 2nd sprocket without a lock ring saying he's never needed one on one of his track bikes: "And I used to race bikes 50 mph!"

Actually, with a rider as strong as the OP, it makes more sense to get a fairly weak chain instead. Then the chain could be sort of a sacrificial fuse that would break instead of bending cranks and stripping nipples out of rims and the such. Better to replace a chain than to have to deal with the systemic damage 400w will do to the rest of a bike. I knew a guy once who was such a strong rider he would saw halfway through the pedal axle so that it would break first. Otherwise he was kinking frames all the time with his power.

jim

BADUMP TTT!

Actually, you do. Having the NJS stamp has absolutely no bearing on the strength / toughness of a chain. NJS is a quality-of-production standard. Similar to ISO9000 in this regard, ISO9000 says nothing about how good a business process actually is, rather it simply assures that the process is to the same quality standard of other processes. So, having the NJS stamp does not follow by necessity that it is any stronger or tougher of a chain.

I use the KMC-710SL and it's fine. Beefy, strong, I've never had an issue. The latter part of your post was probably said to you in a comical fashion - I believe you are actually fined if you skid on a track, unless some sort of ridiculous crash happens (read: Austrailia) and even then pedaling backwards by necessity is questionable. I think he said this half serious half joking since so many people are concerned with fashion and skids (to each their own) over simply riding (the perspective he comes from).

SRAM, hands down. I have not had one of their chains snap on me yet. KMC is absolute garbage. Plates and pins are made of weak metal.

When you make empirical claims, you should back them up with empirical references.