Bicycle Mechanics - drivetrain worn

ok, i was lazy and didn't replace my chain early enough last year. i bought a new full suspension bike (Specialized FSR XC Comp) in March 2002 and then rode 3800km and 65,000meters vertical in the last year... without changing the chain.

then i "retired" my full suspension for the winter and rode my old hardtail to spare it from the salt. now that spring is here i got it back out and the chain is badly strechted - on the rear cassette you can see that it doesn't fit properly. so last week i bought a new chain and installed it and what i feared was true: the front chainrings are worn too much to the old chain: the middle ring skips and the small ring has REALLY bad chain-suck. so for my ride Sunday i put the old chain back on and could not use the middle ring b/c it skips, but the little and big work ok.

so, here is the question: how much do i probably need to replace?
small ring: yes - chain-suck with new chain b/c worn to old chain
middle ring: yes - seems to be worn badly b/c it's skipping with both the old and new chain

how do i know if the rear cassette is OK?

i read somewhere (i trhink Sheldon Brown's writeup on chainsuck) that for the small ring it is best to buy steel or even better titanium and not aluminum as it wears too easily. anyone have any comments here?

if i already have to replace the small and middle ring, is it best to replace the whole front set-up and buy all the rings and the crank together? (i.e. is it cheaper or just a good idea to replace that other stuff if the rings are so worn?)

There was a post no too long ago here about how to tell if a cassette was worn out. For the chainrings, you don't have to replace the crank at the same time as the chainrings. I don't think it would be very economical either, depending on the level of the cranks you currently have. Most chainrings are designed to be replaced as individual rings while keeping the same cranks you currently have. I would just opt for a set of the rings. When buying chainrings and cassettes, make sure you stay with the same size chainrings and same cassette-tooth span unless you are looking to do some adjusting and possible buying a new front der. Sounds like the new bike has a lot of riding on it!

-Moab

If the front gears are worn, it is time to replace the rear cassette.

From my experience I would say the order of wear goes chain, cassette and chain rings. On my road bike I go through about three chains before I replace the cassette. The chain rings last a long time on a road bike, especially the large one.

On my mountain bike the same is true for the chain and cassette, but I spend about 80% of my time in the middle chainring. I have to replace this about once a year. The grunge and sand really shortens the life span of a mountain bike drive train.

I have found it is cheaper and more realiable to periodically change your chain, than to let the cassette wear out. Cassettes cost $$$. Buy a chain ruler, it is money well invested.

the best thing to do is start from scratch buy a new rear cassette, chain, and chainring set, install in after that replace your chain every month or month and a half this will prolong your drivtrains wear, but honestly you got alot of kms outa yer drivtrain and no matter what you did metal wears out dont forget to LUBE LUBE LUBE

well, i replaced the middle and small chainring today and installed the new chain... and everything seems fine, so i think the rear cassette is ok, as i would expect it to shift or crank funny if the rear cassette were also worn.

so i'll be replacing my chain more frequently this year.