Chain/drivetrain life

[OakLeaf]

Okay, I used to race years ago, burned out and didn't ride at all for 12 years, and I'm back to cycling as of a year and a half ago. I think I have a decent handle on this stuff, but I have one question.

When I replace the chain, should I also replace the chainrings? On a motorcycle, you always replace chain and both sprockets together. What I'm reading here is that, for the same reasons, you should replace the chain and the cassette together, but no one has mentioned chainrings.

My chainrings actually look more worn than the rear cogs at this point (1500 miles or so on the new bike), which is logical since each chainring sees more use than each individual freewheel cog.

Input, maintenance pros? TIA Oak

[lph]

My understanding is that you replace the chain and cassette (at the same time, because they "wear together" - though I know a few who insist you can run 2 chains to 1 cassette) early enough to save wear on the more expensive chainrings.

Once the chainrings are worn you replace them too. You can replace them individually on some bikes, not on all. And then you should replace the chain and cassette at the same time.

The upside is you then have a brand-new drivetrain, which is great!

[maillotpois]

lph is generally right, but I will generally go through 2 -3 chains before I need a cassette change - with a SUPER thorough cleaning of the cassette and checking for wear when changing the chain.

I've gone through about 4 cassettes and 8 chains on one bike (replacing chain at 2500 or so miles, when stretched) before needing to replace rings. Even then, you may not need to replace all the rings, just the ones that are most worn.

[lph]

lph is generally right, but I will generally go through 2 -3 chains before I need a cassette change

Oh good. I've always thought that theory made sense, but every time I mention it at the lbs somebody tries to talk me out of it...

[kfergos]

When I replace the chain, should I also replace the chainrings?

In my experience, I haven't had to replace anything but the chain when the chain wore out. So far I've been able to do two chain replacements for every chainring I have to replace. Of course, the more diligent you are about keeping your chain clean (and depending on your riding environment, of course; in New England in the winter, NO amount of diligence will save your chain, chainring, or cassette) the longer everything's going to last.

[BleeckerSt_Girl]

Hmmm.....still on my first chain at 4,500 miles.....maybe I should get a new chain? Seems to be working fine.

[Aggie_Ama]

Lisa- I took my bike in at 2,600 miles because the last wrench told me to replace the chain at 2,000. The guy measured it and said it is not near replacing. He guessed I am a "soft-pedaler" and therefore am getting more life out of mine? He said keep it clean and drop by in another 750-1,000 miles.

They measure the chain with some little gadget, maybe you could get one of those? My husband is just replaced his second chain and chain rings still look close to new. He is very diligent about keeping the drivetrain clean. Oh yeah and the bike has about 8,000 miles on it! They did advise he will need a new cassette on the next go round- gulp he rides Dura Ace.

[lph]

They measure how much the chain stretches, and at a certain percentage of stretch they recommend you change it. If the chain and cassette are badly worn the chain will start skipping, depending a bit on how you pedal.

You can see if the cassette (or chainrings) are getting worn by looking at the teeth (are they called teeth in English? anyway) - they'll be sharp on top and the chain will have gouged on one side creating an assymetrical profile like waves, while new they'll be "mesalike"- flat on top and symmetrical sides.

[Blueberry]

Lisa-

You can measure with a ruler - on a new chain, it's exactly 12" from middle of pin to middle of pin. If it has stretched to more than 12 1/8", then you are looking at a chain and cogs likely (according to my LBS). Of course, you could choose to run it until the chain and cogs need to be replaced, and wait until the performance suffers (that's another school of thought on the subject).

CA

[BleeckerSt_Girl]

Thanks guys.....
I talked with DH and he suggested after this Autumn riding season is over we will get me a new chain whether i need it or not. I do not see much wear on the teeth/cogs. I do keep my drive chain pretty clean and lubed most of the time.

[boy in a kilt]

Okay, I used to race years ago, burned out and didn't ride at all for 12 years, and I'm back to cycling as of a year and a half ago. I think I have a decent handle on this stuff, but I have one question.

When I replace the chain, should I also replace the chainrings? On a motorcycle, you always replace chain and both sprockets together. What I'm reading here is that, for the same reasons, you should replace the chain and the cassette together, but no one has mentioned chainrings.

My chainrings actually look more worn than the rear cogs at this point (1500 miles or so on the new bike), which is logical since each chainring sees more use than each individual freewheel cog.

Input, maintenance pros? TIA Oak

The answer is if you want to be absolutely sure, then go ahead.

Lisa was dead right about the chain, if it's stretched, then replace it. But also, chains have more opportunities for wear. Apart from stretch, there is wear in the individual links, and where the pins go in.

My advice is to replace the chain as needed. If the new chain works fine on the old chainrings and cassette, don't worry about it. I've put 10,000 miles on a cassette and 15,000 on a set of rings.

A lot of bike shops will recommend you replace things that might need replacing in the next year because once they touch your bike, they are liable for anything that could possibly go wrong with it even if they didn't actually do anything to that particular component.

[annie]

When I replace the chain, should I also replace the chainrings? On a motorcycle, you always replace chain and both sprockets together. What I'm reading here is that, for the same reasons, you should replace the chain and the cassette together, but no one has mentioned chainrings.

TIA Oak

Go ahead and replace the chain. Then go for a test ride and see if it skips as you're riding. If the shifting is not smooth, if the chain jumps gears all by itself, without you shifting, then, yes, you need to replace the chainrings, also. If it rides well, why fix what's not broken? If the chainrings look worn, its likely you'll have replace them, but why not test it out first?

Annie

[OakLeaf]

Thanks all for your responses.

Just so you know where I was coming from, if you put a new m/c chain on worn sprockets, you'll have drastically accelerated chain wear because of the worn teeth. It could shift just fine at first (yes, shifting is where you notice it first, even though the chain doesn't get displaced - because of inconsistent tension on the countershaft sprocket and therefore on the transmission gears). But you'd only get half the expected life out of the chain, or less.

On a b/c, obviously the forces are much less, but the materials are also much smaller and lighter, so I wasn't sure.

And come to think of it... a set of m/c sprockets costs less than a chain of comparable quality. So you don't want to wear out the chain prematurely if you don't have to. On a b/c, obviously chainrings and cassettes cost way more than chains. That alone answers my question, I suppose. See what happens when you think about something?