11-34 to 12-36 same chain length?

[scotsbikester]

I've got a nine speed triple setup. M772 RD, R6503 FD, 24-36-46 crankset, ST-6510 STIs, 11-34 cassette.

If I change the cassette to a 12-36 will the chain need shortening?

Thanks.

 

[T4tomo]

I've got a nine speed triple setup. M772 RD, R6503 FD, 24-36-46 crankset, ST-6510 STIs, 11-34 cassette.

If I change the cassette to a 12-36 will the chain need shortening?

Thanks.

if anything it may need to be a link longer. your max point on old was 46-34, its now 46-36, but same length will probably be fine

the derailleur spring takes care of the change from 11 to 12 on the "slack" points.

best thing to do is fit new cassette and carefully check for length with old chain, and then cut new chain to either same length or longer if necessary. You need a new chain anyway as running an old chain on a new cassette will exacerbate cassette wear.

 

[Jameshow]

Unless your chain is nearly new I change the chain tbh, otherwise you'll wear it out prematurely. Fie the sake of £10 it's not worth it imho..