Hi guys, After messing around with 2x9 for a couple of years it was time for a new drivetrain which I've just fitted, including a triple up front. When in the big ring, and especially in the smaller gears on the cassette, the bike sort of 'rumbles' I remember this used to happen the last time I had a triple on the bike but thought it was down to wear. Now everything's new and it happens pretty bad. the chain seems to vibrate and flap about. Is this normal? anything I can do to make it smoother? any tips appreciated.
Chain 'Rumble' in big ring
Off the top of my head I'd check, B screw adjustment, outer travel stop screw on the mech (could need moving out a little) and chain length. Chain flapping sounds like it might be slightly too long, although this usually shows up on the granny ring in the longer gears.
I'm assuming the 'rumble' is not very slight contact of the chain on the front mech, which tends to be more of a grating or buzzing noise.
+1 for B-tension screw. Wind it in till the jockey wheel moves away from the cassette and then try riding it. Then bring it back as much as you can. Have you fitted a larger cassette?
Also check inside the derailleur - a bent cage or rubbing inside the cage.
Replaceable gear hanger alignment?
Also - it may just need to wear in. Ride it a little and look for where the wear is. I had a funny rumble on a bike recently and it was a wider chain on a SS setup rubbing on the bash guard. I tracked it down after a few mins because I could see the scoring!
Thanks Neil. There is no contact with the front mech and all gears are working well. It may be chain tension, or lack of it; I've always just measured the new chain against the old one instead of checking it properly, so I will check. I will also check the B screw and limit screws. Thanks.
Thanks for the tips Gofaster, especially on the B screw adjustment. The new cassette is the same size as the old. I guess the hanger or mech could be bent, its had quite a beating over the years.
Daft question perhaps - you did fit the new chain on the new drive train?
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