Shaking?

[xxxBlakexxx]

Maybe the tire place knocked the weight off on purpose so you would come back (lol).

Anyway, think of it this way. Have you even seen a celing fan wiggle when it is spinning? They get like this when they get dirty or bumped. Imagine what happens to a tire when it is not balanced. It can cause large amounts of vibration.

A sure sign of an unbalanced tire is that the vibration will start at a particluar speed and then go away, unless it is really bad.

If you don't balance the tire, the tread will get cupped and feathered if you drive on it for a while and you will have to replace the tire...and this means usually replacing at least two.

I think it is a good idea to balance tires every other rotation.

As far as the previous owner bumping the rims, they are probably fine. You need to smack a curb hard or hit a pot hole hard to warp a rim...especially with aluminum rims. Aluminum does not bend as much as steel.

For the other guys: Do you have to go to a special tire place to have weights mounted on the inside of the rims?