Jockey wheels

always_tyred
always_tyred Posts: 4,965
edited December 2009 in Workshop
Originally posted in Commuting.....

Okay - replaced 10sp Shimano cassette with identical 10sp cassette, replace Sram chain with identical Sram chain.

Now, when in a low gear (21, 23 and 25) and the small ring (34T) the chain is riding around the lowermost jockey wheel, causing the rear mech and chain to buck and the gears to skip.

I replaced the jockey wheel in case it was sticking, but its doing the same thing.

Not a seized chain link. Chain line identical to previously, yes I remembered the shim, and works okay in the big ring, even though this crosses the chain. So, the cassette seems to be installed correctly (I mean, I've done enough of them by now).

I shortened the chain as much as I dare.

Any ideas what the problem is? I'm stumped.

Comments

  • Nuggs
    Nuggs Posts: 1,804
    Have you tried turning the jockey wheel around the other way?

    Have you bent your rear deraillieur hanger?
  • always_tyred
    always_tyred Posts: 4,965
    Nuggs wrote:
    Have you tried turning the jockey wheel around the other way?

    Have you bent your rear deraillieur hanger?
    The hanger is fine, but the answer to the first question is "no".

    It also reminds me that the "spare" wheel was whipped from a 9-speed. I recall that the wheels are identical but I could try removing a spacer/reversing it, to reduce the deviation of the chain line from the chainring.

    Thanks.
  • skyd0g
    skyd0g Posts: 2,540
    ...sounds like the 'B' tension screw to me...
    check settings here: http://www.parktool.com/repair/readhowto.asp?id=64
    Cycling weakly
  • always_tyred
    always_tyred Posts: 4,965
    skyd0g wrote:
    ...sounds like the 'B' tension screw to me...
    check settings here: http://www.parktool.com/repair/readhowto.asp?id=64

    Don't think its this - the lower jockey wheel is unshipping, not the top one and I don't see how this adjustment would change that.

    Personally I've never managed to make that screw have a blind bit of difference to my shifting, unless I take it absolutely miles out. Hands up anyone who has.
  • skyd0g
    skyd0g Posts: 2,540
    Always Tyred wrote:
    skyd0g wrote:
    ...sounds like the 'B' tension screw to me...
    check settings here: http://www.parktool.com/repair/readhowto.asp?id=64

    Don't think its this - the lower jockey wheel is unshipping, not the top one and I don't see how this adjustment would change that.

    Personally I've never managed to make that screw have a blind bit of difference to my shifting, unless I take it absolutely miles out. Hands up anyone who has.

    ...my mis-understanding of your description. :?
    Cycling weakly
  • Jon8a
    Jon8a Posts: 235
    Try replacing the ring at the front? If the chain and casette were badly worn it might be as well.

Categories