Wheels going out of 'true'

GEPC
GEPC Posts: 123
edited March 2008 in Commuting chat
I have been having trouble with both of my wheels going out of 'true'. I am upgrading the bike soon anyway so hopefully this will be a short lived problem. However the bike (Trek 7.3 fx disc) is only 6 months old and I have already had the back one corrected once and a few weeks later its worse again than ever. Can I take the bike shop to task on this?

Can anyone tell me how this happens. Is it simply that they are poor quality wheels (Bontrager race lite) or is it something else? I use the bike for commuting in London and it does between 40 and 50 miles a week.
As I said I am changing bike soon, but I am annoyed that I will have to get them straightened up again to make the bike more saleable and even more so that I have to put up wtih a disconcerting wobble in the meantime.
Any tips or wisdom welcome.

PS - if anyone want to buy the bike please shout. Appreciate however that this is probably not the best advertisment!