Chain and rear casset life

Bikerbaboon

I replaced my chain last night as it was worn. (using the chain tool 1% was a very tight fit.) and now the chain is skipping on the rear sprockets when i put the power down ( going up hill or sprinting or strating out in a higher gear.)

Im going to re set up the rear mech at lunch to see if that makes a differance, as it looks out of line with the gears slighly.

but i was thinking a chain at 1% would that need a new casset as well ?

T1berious

I might be wrong here but I was under the impression that when ever you change the chain you change the sproket.

I've always done it that way and have never had jumping chains etc. the Park tools web site has a good page on chain wear etc.

T1b

Bikerbaboon

i have seen that as well but i have also read that you can get 2 chains worth of life from a casset ans i was hopeing to be cheap here But if i need i need so of the the LBS to day for me then.

nicklouse

how worn the chain is is not relevant. how worn the cassette is.

but the chain may wear in soon and the jumping will stop but the chain life will be reduced.

dav1

i try to replace before the chain gets to the 1% point personally.

Read that if well looked after a casette can last a few chains.

Bikerbaboon

Well i have called my local and they have got in a new casset for me and will charge me the massive sum of 5p to fit it so i may as well get it done.

stumpyjon

I think the general recommendation is to change the chain at 0.75% stretch which increases the chances of the cassette lasting longer. Most damage occurs to the cassette teeth when the chain is stretched as the rollers catch on the teeth of the sprockets rather than sitting nicely into valleys as they do when the chain is new. Whilst Nick is right that the amount of chain stretch and casstte wear aren't directly related, the more a chain is stretched the longer it is likely to be have been in the stretched condition and therefore there is more chance of there being wear on the cassette.

tjm

I've just replaced a chain that I let stretch to 1%. I then had to replace the cassette and chainrings as they skipped on the new chain.

To be honest I am always suprised at the 1% limit. To me, 1/10th inch in 10 inches is a lot of stretch when you consider how it is made and the fact it has to mesh with the cassette and rings without wearing them.

In future I will not be so lazy and replace the chain when it gets to 0.5% max, I suspect it will be much cheaper in the long run!

btw. I measure stretch with a ruler, I an not convinced the measuring gauges are really measuring what you want to know.

dav1

the guages are very good when used correctly.

I have the basic park tool one and replaced my chain just before the 1% fitted (0.75 fitted comfortably) on my commuter/road bike and there were no chain skip issues what so ever.

tjm

the reason I am not convinced about the gauges is what they measure, not how accurately they do it.
They measure how far apart you can push the rollers of the chain.
What you really want to know is if the pitch of the chain has increased - that is what is going to kill your rings and block.

Whether that is really a problem or not is a moot point. But I don't thing everyone needs to rush out and buy a gauge when a ruler does the job just fine and is so easy to use.

On the subject of wear, I normally have more problems with chainrings that sprockets. Think about it this way....
On my 32 tooth middle ring the chain is contacting roughly 16 teeth at any one time. Over 16 teeth, at 1% stretch the chain is 0.08" or 2mm too long. Meaning that, to get even load over all the teeth on the chainring the last one needs to have worn away by 2mm. that is what will happen if you run your 1% stretched chain on an alloy ring for too long.
Even at 0.5% your are talking 1mm which still sounds a lot.

I hope I got my sums right :?

I only really started looking at this when I realised that leaving a £15 stretched chain on too long had effectively cost me £80 in block and chainrings

streako

Take a good look at your cassette (you may have to clean it first) and you can tell if it is worn or not.

Also check the chainrings on the front as they can slip and give the impression of slipping sprockets.

To be on the safe side I would replace the whole drivetrain. It should last at least a year or more depending on your local trails and how much you ride.