rubbing noise - becoming expensive

ashleydwsmith
ashleydwsmith Posts: 693
edited May 2015 in Workshop
Evening all,

Look 675 with ultegra, i have noticed recently that there is a 'rubbing' noise when the middle to the bottom (smallest sprocket). I can only liken it to sounding like the chain is rubbing the mech but it isnt that.

I have changed the jockey wheels, new chain and new cassette. Havent changed the BB yet. I have noticed that there is a small amount of play in the rear mech, left to right play and took it to a shop to day and they said the cage looks a bit bent. So bought a new mech. havent fitted it yet, as worried i put a new mech on it sounds the same and ive lost £40.

Any ideas- by the way it happens every pedal rev on the driveside.

Comments

  • jgsi
    jgsi Posts: 5,062
    Radical bike.. grown on me
    anyways could a few things... didnt the bikeshop check the rear derailleur aignment for you? not good if they didnt.. presuming the bike is fairly new
    Is the cassette nice and tight?
    Correct spacers involved?
    A month or so ago, I got the spacers mixed up on a cassette I was swapping.. and the bike sounded like a bag of nails.. even though it shifted thru the gears.
    I reckon the shop should be refunding a bit of money or goodwill
  • trailflow
    trailflow Posts: 1,311
    Chainring bolts tight ?
  • ashleydwsmith
    ashleydwsmith Posts: 693
    trailflow wrote:
    Chainring bolts tight ?

    Done them up last night, but probably only a quarter to half a turn on each.
  • thebadgerboy1982
    thebadgerboy1982 Posts: 266
    Could be the mech hanger being bent / out of line. Happened to my bike after the chain got stuck. Shifted fine throughout the range but didn't feel smooth and jumped in some gears.
    Thebadgerboy1982@gmail.com
  • ashleydwsmith
    ashleydwsmith Posts: 693
    thebadgerboy1982 wrote:
    Could be the mech hanger being bent / out of line. Happened to my bike after the chain got stuck. Shifted fine throughout the range but didn't feel smooth and jumped in some gears.

    Mech hanger looks straight as an arrow.
  • trekvet
    trekvet Posts: 223
    Shoe rubbing on crank. Check cranks for scuffs both sides. Pedal with alternate feet out of pedals.
    The Wife complained for months about the empty pot of bike oil on the hall stand; so I replaced it with a full one.
  • ashleydwsmith
    ashleydwsmith Posts: 693
    Took it to another shop, where I got great service. He detected a slight bit of play in the rear hub, and has tightened it up. Hopefully that's the problem. If wheel was moving on every downstroke and causing the rear cassette to move slightly and thus cause the chain to rub the cassette? Here's hoping anyway!
  • patrickf
    patrickf Posts: 536
    ashleydwsmith wrote:
    thebadgerboy1982 wrote:
    Could be the mech hanger being bent / out of line. Happened to my bike after the chain got stuck. Shifted fine throughout the range but didn't feel smooth and jumped in some gears.

    Mech hanger looks straight as an arrow.
    Doesn't mean it's not bent. Get a hanger alignment tool and check it. I had very similar issues on my bike - affected the larger sprockets rather than the smaller ones.
  • ashleydwsmith
    ashleydwsmith Posts: 693
    so went to another shop - they took a look - rear wheel had a tiny mount of play in the hub. tightened up and hey presto.
  • on-yer-bike
    on-yer-bike Posts: 2,974
    It might not rub the front mech when on the stand but with some of these pushfit BBs the movement caused when laying down the power can cause rubbing when in the smaller sprockets. A friend had to have the BB changed on a brand new, expensive bike for that reason.
    Pegoretti
    Colnago
    Cervelo
    Campagnolo
  • dee4life2005
    dee4life2005 Posts: 773
    Couple of things - some possibly obvious, so apologies for mentioning if you've already checked :wink:

    1) Chain incorrectly routed through the rear derailleur cage.
    2) Crank arm rubbing against front derailleur cage on pedal revolution
    3) Crank arm rubbing against excess front gear cable.
    4) Bulge in tyre side-wall catching brake blocks.
    5) bottom bracket bearings gone? any lateral play in cranks?
    6) I've also had play in rear wheel hub before that made a similar noise as the play wasn't enough to notice in stand, but when putting power through the pedals it made the wheel move laterally enough to rub against the brakes.

    ** edit, my money would be on No. 6
    http://app.strava.com/athletes/307297
  • ashleydwsmith
    ashleydwsmith Posts: 693
    dee4life2005 wrote:
    Couple of things - some possibly obvious, so apologies for mentioning if you've already checked :wink:

    1) Chain incorrectly routed through the rear derailleur cage.
    2) Crank arm rubbing against front derailleur cage on pedal revolution
    3) Crank arm rubbing against excess front gear cable.
    4) Bulge in tyre side-wall catching brake blocks.
    5) bottom bracket bearings gone? any lateral play in cranks?
    6) I've also had play in rear wheel hub before that made a similar noise as the play wasn't enough to notice in stand, but when putting power through the pedals it made the wheel move laterally enough to rub against the brakes.


    You were right number 6 it was
    ** edit, my money would be on No. 6

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