Oscillating cassette

Fru T Bunn
Fru T Bunn Posts: 159
edited March 2009 in Workshop
Hi,

When my rear wheel spins and I look down onto the cassette I can see it oscillating from side to side very slightly.

Is this normal? If not, what could be causing it? Incorrect fitting of cassette or freewheel and/or a sign that the wheel is out of true?

Many thanks,
Andy

Comments

  • cougie
    cougie Posts: 22,512
    seems pretty normal on my bikes. Never caused any problems anyway.
  • bnmcmhn
    bnmcmhn Posts: 40
    Bear in mind that modern cassetes have ramps to improve shifting. Sometimes these ramps can give the illusion of wobbling when the cogs are spinning.
  • alfablue
    alfablue Posts: 8,497
    Is your cassette lockring loose? This has happened on one of my bikes, culminating with poor shifting to the smallest sprocket. Despite re tightening to the correct torque it repeatedly happened, fixed with loctite on the threads.
  • flasher
    flasher Posts: 1,734
    bnmcmhn wrote:
    Bear in mind that modern cassetes have ramps to improve shifting. Sometimes these ramps can give the illusion of wobbling when the cogs are spinning.

    +1

    I thought mine was wobbling too until I looked much closer.
  • woody-som
    woody-som Posts: 1,001
    my winter 8 speed does that, cant find a reason, new axle and hub bolt fitted. The wheels on the summer bike dont, so just put it down to one of those things, not caused any problems.
  • Wappygixer
    Wappygixer Posts: 1,396
    Nearly all Shimano hubs do this.I think its because the still use cup and cone bearings even in the free hub.
    Its just a little play as to avoid it being over tightened
  • huggy
    huggy Posts: 242
    Yep when looking at my old Peugeot's RSX cassette when turbo training, there's some serious movement. Doesn't seem to cause any problems though.
  • If it's a Mavic wheel it could be because the freehub body is worn - can be a problem if you don't service them often enough. It causes the cassette to rock from side to side.

    One thing cassette rocking can do is mess up smooth indexing, so your gear changing goes to pot.
    It doesn't get any easier, but I don't appear to be getting any faster.
  • Anonymous
    Anonymous Posts: 79,665
    When I cycle I don't notice any movement but sometimes when bike is upside down and I'm spinning it I can see sort of movement side to side, like wobbling very slowely.
  • John.T
    John.T Posts: 3,698
    Most Shimano freehubs do this when free wheeling. It does not cause any problems.