Rear Cassette Problems

Hi,
My rear cassette has about 7 gears. When It is in the middle of the gears, 3 or 4 for example, the chain pulls the gear cog around but the cog simply rotates without actually turning the wheel, i.e. there is no tractive force between the cog and the axle, could some one tell me what is wrong with it?
Thanks
Richard.
My rear cassette has about 7 gears. When It is in the middle of the gears, 3 or 4 for example, the chain pulls the gear cog around but the cog simply rotates without actually turning the wheel, i.e. there is no tractive force between the cog and the axle, could some one tell me what is wrong with it?
Thanks
Richard.
0
Posts
or is the whole cassette moving? if the later then the freehub/body is dead and either needs a service or replacing depends on the hub used.
Parktools :?:SheldonBrown