How bad do rims need to be bent to have a *shakey* ride?

[Le Nitro]

I put my fathers e46 OEM 16x7 wheels on my e36 with his winter tires today and I remember in his car once you got to around 60mph you could hear the tires/wheels. The tires are brand new and he had them balanced, etc.

I just got them on in the afternoon and got it up to around 60 and its doing the same with me. It's not getting shakey, firm wheel, no shakes etc, but you can hear the tire/wheel noise get loud.

Here is the thing that is throwing me off...I was running 17x8 wheels w/ 245/40 and 225/45 toyo's.

My wheels on a bump would kind of turn pretty rapid by itself so I always had a firm grip on the wheel. I had all 4 rebalanced when I put 1 new tire on because I got a flat. They have maybe 40-50% tread life left. The outsides are pretty worn from autocrossing though.

I do not have that rapid/violent whip with this setup, it's just loud.

The wheels do not look bent, and my fathers mechanic told him the wheels were bent, but compared to my old e36 oem wheels which were also 16x7 they didn't make nearly as loud noises. Is it maybe because of the tire, or do slight bends that the eye can't see really make a huge difference?

Thanks for your help.

-Mike

P.S. Like I said it gets noisy in the higher speeds and I will be heading out on the highway with these this upcoming week probably hitting an avg speed of 70mph but sometimes 80-85, is it dangerous to drive at those speeds with my setup(the tires are good, I just mean the noises).

Edit: Took it for a highway run yesterday, once I got past 65mph you could start to feel a vibration in the wheel and it pretty much stayed like that all the way up to 85mph.

[Le Nitro]

Nobody here can help me with that?

[GunnerNell]

I'm no expert, but here's my take on that -- Yes, a tiny bend in a rim, even one you cannot see, can cause this. But not necessarily. I think tire noise is more a function of the tread design (and probably the rubber compound) than anything else, and that's why you hear it more or less at different speeds. It has to do with the way the tread hits the road and the harmonics generated by the tread design. But a bent rim will cause the shimmy, IMO. I can't say (or not say) it's dangerous, necessarily, but it certainly isn't optimal to drive around in a car that doesn't have the wheels flat on the tire's sweet spot at all times. If it were my car, I would not drive it at high speeds on a bet, and I'd worry about the damage I might be doing to the suspension components, maybe not serious damage, but life-shortening to the components. And btw, on your own set up, I think it's a bad idea to put one new tire on a car. I've always heard you should replace tires in pairs, by axle, especially when one has less than 75%, say, of it's tread left. Like I said, I'm no expert. You'd be wise to find one and go over all this with him/her.

[Balthazarr]

I'm no expert, but one of my rears was bent so badly as to actually straighten out about 1/8 of the inside bead.
Still held air at 16 lbs.
I beat it back and now it holds 30 lbs. Not a rough ride, but needs replacing, so I don't have to fill with air every other day.

[M62pwrdE38]

I would take them to a shop with a RoadForce balancer. One or more of the tires or wheels might be out of round or bent enough that it will cause a vibration even when balanced correctly. A RoadForce balancer can detect excessive runout and determine if the wheel or tire is the culprit. Also, what kind of tires are the snows?

[BQuicksilver]

Get the wheels/tires roadforce balanced.

You may also have a toe issue based upon the noise and quirky handling.