Chain length

[PooPoo]

Hi, im upgrading from 2x9 Sora to 2x11 105, but I'm changing the cassette to 11-32 using a medium cage and compact front chainset. So i can't just copy the length of my old chain, is there an easy way to gage the length required of the new chain? Thanks PP

[IroningMan]

Put the chain round the larger chainring and the 32 cog at the back, and add two links.

NB - just the chainring and the 32, leave out the jockey wheels.

[Razor O Rourke]

Or do it the easy way -

http://www.machinehead-software.co.uk/bike/chain_l...

Foolproof method, works every time.

[Barchettaman]

I've had success sizing the chain small-small.

http://www.slowtwitch.com/Tech/Chain_How-To_-_Part...

Edited by Barchettaman on Friday 8th September 22:00

[gazza285]

Always done them small/small, even when I worked in the LBS, leaves a bit of room for expansion, and more links last longer...

[IroningMan]

Vive la difference.

[PooPoo]

Razor O Rourke said:

Or do it the easy way -

http://www.machinehead-software.co.uk/bike/chain_l...

Foolproof method, works every time.

Cheers, when You measure the chainstay is it from centre of BB to quick release rear wheel?

[Steve vRS]

Is it really just two extra links? As a layman I'd have thought by the time the chain goes around the jockey wheels, that would be a bit of length. Every day is a school day!

[IroningMan]

Yep. Just two. As espoused by Park Tools and Shimano - works for me, at any rate.

[Razor O Rourke]

PooPoo said:

Cheers, when You measure the chainstay is it from centre of BB to quick release rear wheel?

Yes, centre to centre.

[HardtopManual]

Put it in small/small and make the chain as long as you can without the chain fouling the derailleur.

[PooPoo]

Thanks everyone, I have just checked my Sora setup and running the chain over the 28-50 showed the two spare links so I'm gonna use this method which I guess would be the same as small small without fouling. Thanks again

[louiebaby]

HardtopManual said:

Put it in small/small and make the chain as long as you can without the chain fouling the derailleur.

This is what I've always done. Erring on the side of slightly shorter to allow for a bit of wear, if it's not immediately obvious.

I'm not bothered about making the bike as light as possible, so having a few less links wouldn't really help me much.