Rear Derailleur Chatter
#1
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Joined: Jan 2004
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From: Portland & Yachats, OR
Bikes: Steve Rex, Seven Axiom, Felt Z1, Dave Moulton Fuso
Rear Derailleur Chatter
5 year old 11 speed mechanical Ultegra group - always worked fine and recently moved to a newer frame. System and rear derailleur shifts perfectly and everything seems fine...until...
When descending over a rougher road (chip seal) and not pedaling, I hear a chatter that sounds just like chain slap. But I can't see or find any physical evidence that that is what it is. And it goes away when I continue to pedal. For a moment, I thought it might be the rear hub but that's been checked and cleared.
I'm now thinking B screw adjustment but if anything, its adjusted a hair too far from the cogs as opposed to too close.
Thoughts?
Thanks!
55/Rad
When descending over a rougher road (chip seal) and not pedaling, I hear a chatter that sounds just like chain slap. But I can't see or find any physical evidence that that is what it is. And it goes away when I continue to pedal. For a moment, I thought it might be the rear hub but that's been checked and cleared.
I'm now thinking B screw adjustment but if anything, its adjusted a hair too far from the cogs as opposed to too close.
Thoughts?
Thanks!
55/Rad
#2
Facts just confuse people




Joined: Jul 2017
Posts: 19,365
Likes: 7,076
From: Mississippi
Bikes: Tarmac Disc Comp Di2 - 2020
Different bike different sounds to get use to.
Though I'd suspect chain slap too. Is this also when in the small tooth count cogs and/or ring? Maybe you need to shorten the chain.
Though I'd suspect chain slap too. Is this also when in the small tooth count cogs and/or ring? Maybe you need to shorten the chain.








