Recently I have bought a used 2012 Cube CLS LTD PRO hybrid bike in a good condition . The only thing was the rear cassette a little wobbling. I asked a mechanic about this and he told that almost every bike has this problem . After riding about 300 km I noticed that the cassette is wobbling more than it had been. Today I took the rear wheel off and saw that the cassette had a tiny backlash on the wheel . Can I fix the wobble simply by tightening the cassette , or should I buy a new one ?
Wobbling cassettes should be absent from, not present on, every bike. It is possible that the wobble is caused by worn splines on what might be a soft (aluminium, as opposed to steel) freehub. I myself recently blogged about such an issue at http://bit.ly/HubTrouble .
The wobble might instead be a result of an incorrectly seated lock-ring, or a missing spacer from behind the cassette (in which case you might find this link of interest: http://bit.ly/CassetteIssues)