On my mags, on the inside there is stuck some little weights which I assume are to balance the wheel out. Are these put on by the wheel manufacturer or the wheel and tyre shops?
I know the ones that clip on the side of the rim (e.g. which I have on my steel wheels) are knocked on by the wheel and tyre shop, but the mag wheel ones are different.

Basically I'm looking at moving the position of my wheel centres on my Simmons and I figure this will effect the wheels balance.

Those weights are for balancing the wheel. If your gonna modify the wheel you'll definately need to get it balanced again. a tyre shop can do that for you. The flat ones on the inside are just a stick on weight and can be put on by any tyre shop.

excellent, cheers.

just make sure u ask them to put on stick on wieghts

other wise the will use the other type which are cheaper and will f**k ya rims