Chain stretch
 

The mechanic at my LBS says I have "Quite a bit" of chain stretch.

I know this messes up the cassette, but will it mess up other (more important and expensive) items like the chainrings or derailleur?

Thanks

Edit: I guess the derailleur shouldn't be affected since it is only the replaceable cogs that come into contact with the chain.

yup!

well just your chainrings...

i have found the cheapest method is to get a chain checker ands check often. you can find chains for 10 bucks; replacing them is easy to do yourself. new drivetrains are significantly more as you are aware.

even if your pretty diligent you still only get like 3-4 chains before you gotta replace the works. but that is usually a good long time.

if you already have siginficant stretch i say ride it till it really starts to look bad. you pretty much know you need a whole new drivetrain next time so get the most outta this one first if it still works good ;) or you might get away with just replacing one chainriing and the cassette? really all depends on the gears you ride.

I've started changing my chains every 2000 miles or so and at that point they hardly show any measurable "stretch" at all. In fact they are still within new chain specs according to my LBS.

At 4200 miles on my new bike my cassette still looks pretty much brand new. Shimano recomends changing your chain every 1500 miles but that is really, really early.

I conjecture that a big variable in how much a chain stretches is riding style. My guess is that mashers tend to stretch chains and ruin cassettes much faster than spinners.

Even worn and badly damaged cassettes often look "pretty much brand new". The damage to the cassette is not something you see... it's something you feel when your chain skips.

You can see the damage. The start to "hook" rather than look uniform on the drive and non drive side fo the teeth.

You can certainly tell by looking at them. Its the same thing for the chain rings.

Hmm..

2 000 miles = 3 218.688 kilometers

I'm almost at 6500km ( 6 500 kilometers = 4 038.91275 miles) with my default stock chain on my new bike. Last time the LBS checked was probably 4000km and said the chain was still good. I'm using Deore (I think LX) cranks and cogs and a HG something chain. I'm taking a guess that it's because of the higher end parts that's why I'm able to to extend the ride time this far. Well that and I do tend to clean my chain very often and lube it which probably also aids in the prolonged life.

I have also found (at least in my case) the cogs you use the most are going to wear the worst...duh! So if you seldom us a certain cog or two you can save a couple of bucks by not swapping those out. I typically swap out chains the moment they show any sign of stretch, I have no clue what kind of mileage I get out of a chain/drive train, but I typically swap out 5 chains to a freewheel/cassette. One issue that I don't have with my fixie or IGH;)

Aaron:)

I checked the chain stretch on all of my bikes a month ago, and found that my winter bike's chain was almost to the max limit, whereas my summer bike's chain, with virtually the same miles as the winter bike's chain, had like new measurements. I attribute the chain wear on my winter bike to heavy loads and last winter's above normal foul weather with it's added road grit and grime. My winter ride is now sporting a new chain, and I will be checking the chain on it more often.

Other factors are if you start and stop like city traffic.

As you place more torque in starting.

I had about 2,700 miles on mine before I changed it on my road bike. It was still within safe specs, but wasn't "like new"

I got 3000 miles out of the first chain. I replaced it when it hit 10 1/16". Second chain 1500 miles replaced when 10 1/16 when I replaced it the cassette skipped like crazy so I just replaced that. From now on I replace the chain at 12 1/16th.

Maybe you right, perhaps some people can see it. I can't. The only thing I can see is non-symmetry that was engineered into the cassette from the start. AFAIK, they are not made perfectly symmetric this day, for the better shifting performance or some such reason.

Also, the smallest cogs tend to go first, since when you're in them you're more likely to be exerting lots of force.

i change mine every 800-900 miles; did it again last night. Any more, and i wear out the casette also.

I'm hard on this stuff, and often stand to climb hard.

And less teeth to exert that force on.
I'm a bit heavy, I mash and cross chain, I mash on hills. So I go through chains as a result.

Do you lube your chain with sand??!!??

ha ha

I had rougly 3k miles on mine, and I couldn't complete a full rotation with out the chain slipping. Ended up costing me a new chain and free wheel.

Well my brand new trek cruiser eats chains for breakfast,I only get about 800-900 miles on one chain,I just replaced one 1.5 months and its already half worn.1/32 elongated.Even though I replaced the chain in time its still wearing the teeth a little.Its no big deal because a chain for me is only $5.00 ate ace hardware.

Spend $15 on a SRAM chain and you'll probably get a better ride and much longer-lasting chains.

Don't bet on it. I've used SRAM chains in the past, and now I use the cheapest, $4.49 Nashbar chains I can find. I get 1800 miles out of anything I've tried regardless of whether it's a $5 or a $15 chain.
My route includes 4 miles each way of gravel/sand/clay roads. If there's any moisture at all on the ground, even a brand-new chain will be completely grunged up in sand after one ride. I think even if I cleaned my chain twice a day I'd still get 1800 miles on it. I've actually stopped cleaning the chain, since it doesn't really seem to matter. I just oil it and then wipe it down.

Well, not everyone can see it. I changed my chain while it was still in the "safe" zone (according to my lil' Park chain measuring thing). It's a new bike with under 2000 miles. Chainring looked okay to me, although that's not a problem I've dealt with before, but I couldn't get it to stop skipping in my mid gears (the ones I spend most of my time in). LBS couldn't figure it out, either, and was in the process of trying to replace the freehub when they finally figured out it was the cassette.

I'm wondering if that's always going to be a problem or if it was just that that first cassette was not so good. All the parts under 2,000 miles, and the chain not stretched more than recommended, so I wasn't expecting it, and I'm wondering if I'm regularly going to have to change my cassette with my chain.

After a little more than two years of service, I just went in to the LBS to change the drivetrain on my commuter. Bought a 11-32 9sp XT cassette for 60€, 44t chainring for 30€, and the chain for 10€. The old chain put side by side with the new one is way streched out by several cogs... didn't count em tho.

However this morning I came in on my roadbike since I wasn't able to get one of 4 chainring bolts off. Don't have the right tool and the thing looks good and frozen.

I'll look into changing the chain more often to avoid replacing the whole drive train. Most of it is new looking, but the gears 15t - 20t looked like shark fins... the rest were newish looking.

Anyway, beats replacing distribution belts in the car...

I checked mine around 1800 miles and there was absolutely no "stretch." Now that Winter is realy hear, and we've had fresh snow every day for the last 4 days, and will continue to see Lake Effect snow for the coming week, my chain is actually getting dirty. I am approaching 2000 miles and no problems. I'll wait till March when the worst of Winter is behind us and put on Fresh chain. All this snow+salt can't be doing the chain much good. I did switch from Pedra Ice Wax to Perdo Synluble. I like the Ice wax as it appears to work very nicely most of the year without leaving the chain very dirty. The Syn lub is clearly much stickier and makes the chain one very nasty mess. The upside of Syn lube is that the drove train is running smooth and quiet even after getting caked with salty slush and snow. So I will use Ice Wax starting on the new chain that will get installed in Spring, and use it throughout Fall, and then switch to Synlube when the conditions deteriorate sometime in December or January.

Happy riding,
André

I think if I were riding on pavement every day my chains would probably last many times as long. However, I ride over gravel/sand/clay mix 8 miles a day. My chain is utterly caked in sand within 2 miles of setting off even with a brand new or freshly washed chain. It grinds them right down.

I recently put in a new chain. 2 days later during the day (30 miles) I checked the chain while walking by my parking spot and it showed surface rust and the links were already stiff. I've started oiling it and wiping it down every 2 days or so (40 miles) for the duration of winter.

Even cheaper get a ruler and measure 12 links,if they dont line up and is 1/16 over,replace,anything over 1/16 replace all your gears.