Hi all, I swapped my cassette from a 11-30 to a 11-34. I also replaced the chain, keeping an extra couple of chain links compared to the previous. The gearing feels much more clunky than before.
The chain seems slack on the smaller sprockets. But seems about right on the larger. Any bike mechanics out there that can advise?
Should I remove a couple of links?
Checked the high and low limit and B screws – nothing seems off.
Thanks in advance!
by jib848
14 Comments
a bit long id say
https://bike.shimano.com/stories/article/determine-chain-length.html
Should be just tense on smallest smallest. So this chain us too long
The chain looks long in the smallest cogs but good in the biggest. This likely means that your derailleur doesn’t have enough capacity for the gear range you’re running now, it can’t take up the slack properly for such a large difference in gearing. It’ll be fine as long as you don’t cross chain, but if you accidentally run small-small and that chain flops off the cogs you’re going to have a bad time.
Do you have enough capacity in the rear mech to handle the extra 4 teeth? Could possibly shorten the chain but definitely too slack in small/small right now so check max capacity on the mech.
Most will likely recommend removing a link, which is fine, but I’d first try tightening the B screw to take up the slack in small/small.
Check b tension
Length looks fine in big -> big – likely just need a b-screw adjustment to get tension in at the bottom end
All this assumes your chain / rear mech are properly routed / mounted
Even if that derailleur is technically capable, if a B screw adjustment doesn’t fix, it obviously is not. Longer derailleur or perhaps an extender. Rattly operation on a new chain is most likely worn chainring, or insufficient lubrication.
11-30 => 11-34 you might need a large cage derailleur.
You’re crossed chained and should never be riding in those gears
Just in case it is unknown by someone. Max capacity on a rear derailleur means (largest cog -smallest cog on cassette)+(largest cog -smallest cog on crank). An example could be (34-11)+(52-36)=39.
Are you really in small small there? I thought that default di2 setup prevents that pairing (can get to second smallest cog on cassette though). Either way you want to avoid being in that gearing combination (same goes for big big).
Measure it.https://bike.shimano.com/stories/article/determine-chain-length.html