[Yak] Shimano B screw and guide pulley drag?

[John S. Allen]

Youi may be able to solve this problem by adjusting the chain length. 
Does it occur with the chain on on one chainring more than another? 
If more on the smallest chainring, the chain is too long (but you 
still need to leave it long enough for large-large  combination) -- 
and vice versa.

You could try removing the rear derailer and screwing the B-tension 
screw backwards as Geof Gee suggested, so the head rests on the stop.

Otherwise you need to get either a smaller cassette or a rear 
derailleur with more capacity.

At 03:41 PM 4/17/2011, j harris wrote:
>Howdy all,
>
>             found an interference between the chain, the largest 
> (32t) sprocket, and the derailleur guide pulley on my wife's spare 
> bike the other day when I foolishly looked at it. I believe I would 
> have seen this before, so I think this is new. the bike is a lower 
> middle class Raleigh mtn bike, low level Shimano (Acera) components.
>
>I cranked the B screw all the way in, and while it made it a little 
>better, it didn't cure it. The screw/stop geometry causes the screw 
>to start sliding off the stop when the screw is all the way in so 
>trying a longer screw didn't help.
>
>I looked at the derailleur hanger, and it appears undistorted. I put 
>on a new derailleur, same problem. Other than ignoring it,  as
>
>1. it's not a bike I ride, and
>
>2. the interference only happens in in fattest sprocket
>
>
>I'm out of ideas. Any thots here? Thanks
>
>Cheers from Fairbanks

John S. Allen

jsallen *at* bikexprt.com

http://bikexprt.com