bikenut2011

going from a 12-26 to an 11-28. the chain only has about 350 miles on it. Will it need to be longer? or am i all set? Oh, both are 9 speed if that makes any difference.

THANKS!!

andy

Retro Grouch 

Probably you'll be OK. If it was my bike I'd gently shift into the big/big combination to be sure the derailleur has a bit more take up slack.

JiveTurkey

How old/worn is the cassette? It's generally a good idea to replace chain with cassette or else the worn/stretched chain will prematurely wear the new cassette.

bikenut2011

chain and old cassette only have like 350 miles... no wear as far as i can see. sound ok?

andy

DiabloScott

Yeah your chain is probably fine but the length might not be. But put it on and check big-big for enough chain, and small-small for enough wrap to make sure the chain is sized OK... if it's borderline tight now, it might be too tight with the new cassette, and if it's borderline loose now... too loose.

fietsbob

the variable is cleanliness and frequent lubrication, 350 miles can do significant wear,on a dry, dirty chain.

don't be attached to chains, they should be replaced frequently
to keep from prematurely wearing down the rest of the, more costly, drivetrain ..

FastJake

As long as the chain hasn't been through rough, dirty use it should be fine with the new cassette. 350 miles isn't that much if it was kept lubed.

Just check the chain length in the big-big and small-small combonations as noted.

bikenut2011

Im really good about keeping the chain clean and lubed... I guess i was mainly concerned about it being too short with the bigger cassette... sounds like most likely it will work ok

andy

FBinNY 

Why don't you just measure the chain instead of guessing. I suspect that it'll be OK, but you could measure and know for sure in less time that it'll take to get a bunch of meaningless opinions here.

If over 12" it's stretched less than 1/64" or so (eyeball 1/4 or the way to the 1/16" mark) go ahead and use it. if it's worn beyond that, switch it out for new, but save it and rotate it back into service when the new chain catches up, or passes it slightly. Thereafter adopt the two chain system leapfrogging them back and forth until both are stretched.

BTW- if you have noticeable stretch after only 350 miles, you need to rethink how you lube and maintain your chains, because your system isn't serving you well.

Note, 2 extra teeth will need 1/2" more chain, so if your chain was measured super close for the 26, then it may be too short for the 28. Then again this is also something you could measure rather than guess.

bikenut2011

Great post, very helpful. I'm pretty good at measuring...20+ year carpenter... I will give it a whirl.

I guess what i was trying to get at in the first place before all these posts about chain wear, was whether or not the 2 extra teeth on the cassette would require me to buy a LONGER chain... I guess i wasnt to clear on that.

thats mainly what i wanted to know...

Thanks to everyone for your assistance

Cheers
andy

FBinNY 

The latter part of my post covered that. 2 extra teeth on a cassette call for 1/2" more chain, It's easy enough to check on the existing cassette. shift to the bib/big combination, put a ruler against the lower loop and see if you can pull 1/2" of chain forward (make sure the crank can't turn) out of the RD cage.

If it looks OK, switch cassettes, but confirm that the chain is long enough by going to big/big and double checking that the RD isn't pulled to it's limit.

bikenut2011

Awesome!! Just the info i was looking for!! Will Do

Thanks so much!!!

andy

bikenut2011

Thanks to everyone that helped out with my Q. The new cassette arrived today, and i am happy to report that i swapped it out without a single hitch. shifts perfect, didnt even have to adjust the RD... and also, the chain is still long enough and has slack on the largest rings.

Loving the new setup and Thanks again!!

Cheers!!
andy