Hello!
Road bike drivetrain is making a grinding noise. BB needed done so I've replaced that but it's still there. Cranks turn freely now but when I turn the pedals backwards there's still a grinding somewhere. Chain not rubbing at the front mech so what else to check/replace or how best to diagnose. Guess it could be freehub, rear derailleur or something else? Got a few long rides coming up so looking to get it in good shape again (unlike myself).
TIA.
Did you split the chain at any point? It's easy to thread the chain the wrong way over the metal tab between the jockey wheels in the rear derailleur and that gives you a noise you could describe as grinding.
(So I hear, I would never do such a thing... er...)
@euain - no, never split the chain. I have done that in the past though 🙂
Could be the freewheel is it dragging the wheel and cranks round on the stand when you stop turning the cranks?
Can you still hear it while turning the cranks with the chain off? You can isolate front or rear that way…
I recently had a grumbly back wheel. Thought it was the hub bearings turned out the freewheel was shot. I remember putting the bike on the stand spinning the cranks. You would then expect the back wheel to freewheel when you stop turning the cranks. This one did not disengage so the cranks kept turning with the inertia of the back wheel. Just think it’s a good indicator of a shot freehub.
