when i am in lowest gear at rear and inner ring at front, there is a rubbing between rear derailleur and spokes , only does this in this particular gear. any idea what could be causing this ?
There are 2 screws on the back of your rear mech cage - tighten the one towards the rear by a turn whilst in the biggest sprocket - it should move away from the spokes
Make mine an Italian, with Campagnolo on the side..
If you've never had this problem before on this specific bike, AND you have not dropped the frame or otherwise knocked it, then cable stretch and an adjustment to the limit screws might be the answer.
Also check whether you have the rear wheel centred correctly in the frame with the QR. DIdn't say whether you have changed wheels at all??
If you *have* dropped the frame, even lightly, it's possible the derailleur hanger has been bent in very slightly which maks the cage hit the spokes like this. If all else fails to fix it, ask the LBS to check that alignment - there is a special tool for it, which they might have.
Open One+BMC TE29Seven 622SLOn One Scandal Cervelo RS
I've just recovered from a broken collarbone (2nd time in 3 years) and took my bike out for it's first ride since the accident. I thought everything was OK, all my changes were as crisp as ever. That was until I put the rear mech into the largest sprocket. The mech was wrenched off the frame and dumped on the ground, having tangled with the spokes. The gear hanger was bent, as was the dropout beyond the replaceable hanger. I concluded that the hanger must have been slightly bent from the original accident, as there were witness marks on the rear mech where it had touched down. Moral of the story - give the bike a thorough check before riding again after a tumble.
To err is human, but to make a real balls up takes a super computer.
If you've never had this problem before on this specific bike, AND you have not dropped the frame or otherwise knocked it, then cable stretch and an adjustment to the limit screws might be the answer.
Also check whether you have the rear wheel centred correctly in the frame with the QR. DIdn't say whether you have changed wheels at all??
If you *have* dropped the frame, even lightly, it's possible the derailleur hanger has been bent in very slightly which maks the cage hit the spokes like this. If all else fails to fix it, ask the LBS to check that alignment - there is a special tool for it, which they might have.
the wheels are handbuilt 32 spoke mavics with open pro rims and 105 hubs, been atomic war proof so far.
I had the same problem on my steel audax bike. It was the mech hanger that was out of line following a dropped bike during a cleaning exercise. I bought a tool from Wiggle and did the job.
This happened to me a few years ago.. put rear mech into largest sprocket 28...rear mech was ripped into the rear wheel ..12 spokes smashed Chain broken....and me, 4 teeth smashed out, broken hand, :oops:...
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i thought you decided it was down to Quad power and wheel flex
ive had the bike for over 2yrs and never had this problem before :?
Also check whether you have the rear wheel centred correctly in the frame with the QR. DIdn't say whether you have changed wheels at all??
If you *have* dropped the frame, even lightly, it's possible the derailleur hanger has been bent in very slightly which maks the cage hit the spokes like this. If all else fails to fix it, ask the LBS to check that alignment - there is a special tool for it, which they might have.
the wheels are handbuilt 32 spoke mavics with open pro rims and 105 hubs, been atomic war proof so far.