Rim out of round

Out of round like an egg or out of round moving left to right when spinning from a headon view?

Reason I ask is I recently put some AMG rims on my MB and when I had new tires put on the guy told me the same thing . He said he had to put a bunch of weights on and it still was not perfect, there was a bit of vibration.

I was concerned about the cars ride (was driving it from NY to FL to leave it there permanently the following week) and decided bring the car to a rim repair shop to have them fixed and they put all on a snap-on balancing machine which determines the balance and it differentiates the tire and rim. The result: rims were fine they rebalanced them and it drives perfect. $20 later I was done. It was like hitting the jackpot.

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Out of round rims can be balanced to minimize vibration but not eliminate it completely
Safe to drive at normal highway speeds but at 9/10ths or more it adversely affects the car dynamics
If the wheels can be corrected great but personally for such high performance cars I usually replace them for peace of mind


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Out of round is the first instance, out of true is what the second is called.

 

I’d be more concerned you were driving around in nearly 7 year old tires.

You need to drive more.

 

Right on!

Drive baby, drive.

 

You can have the wheel fixed so its round. I would also go to a place that has a road force balancing machine. I don't think the one in your video is road force.

 

I wasn't aware you could make an oval rim round again. I have sent new tires back (TireRack) when my installer said they were out of round on a DD. In that case only shaving would get them round again and why bother just send them back. For the rim though, is there a machine that trims them or forges (squeezes) them round again? At high speeds the vibration of out of round is unsafe IMO. Also not good for suspension and steering components.

 

Looks out of round. I’d just get another wheel.


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Agreed all - uh- around lol

I do believe there are wheel shops that can get the wheel back into round. I think it depends on what part is out of round- is it just the edge/ lip? Or is it across the entire wheel? But its probably better to simply get a new wheel. It really depends on the degree. I've had wheels fixed several times with no issues.

No wheel nor tire is perfectly round. Unfortunately as you drive on metal wheels, they are always getting slightly out of round. Its a question of degrees. Thats why you want a road force balance. It will match the low point on the wheel with the high point on the tire. I once had a Pirelli tire with over 140lbs of road force- that is extreme! Pirelli took it back.

 

Ferrari forbids straightening of bent wheels. That said, it doesn't look like the wheel has a simple flat spot on a rim lip from a small impact like a pot-hole, which can be straightened fairly easily. Looking at the video of the wheel, it looks like the entire outside drum of the wheel is not concentric with the inner mounting surface. It almost looks like the wheel was not mounted on the balancer correctly, but I am sure that it was.

This means that the defect in the wheel is in the actual spokes of the wheel, causing the mounting surface of the wheel to not be concentric with the tire mounting surfaces. I would not have this rim repaired and would recommend replacement of the rim with a good used or new wheel.

Road force balancing is a good idea. I am not too fond of Pirelli tires, as they always seem to need a large amount of weight to balance correctly. I have found that Michelins take very little weight to balance, sometimes none at all.

 

Thanks. Right, like the bicycle wheels I would attempt to true as a kid on my old 10 speeds(road bike).

 

That is a severe imbalance.