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[Matt_UKTX]

It seems there's been a lot of talk on the forum lately about people bending rims and having all kinds of problems with the RFT's.

My question is: How can you tell if you bent a rim (or more than one rim). I don't believe I have bent a rim, but I'd like to know what to look for in future. Can you tell from a visual inspection? Where would you look? How does the car feel/ride/sound with bent rim(s)? How does the feeling change at different speeds? Are there any places you can take your car where they can check this (like Discount Tire or something like that)? How does a bent rim feel different from poor alignment, or uneven tire pressure, or worn tires? Any input or comments would be greatly appreciated.

Thanks...

[HRC]

You can tell if you've bent a rim(s) by loss of air pressure, shimmy at all speeds and if you see an indention on the outside lip. That's where most damage happens. Unless the rim is bent real bad, I don't think it will have a drastic effect on the car pulling to one side.

Any tire place can tell you if you have a damaged rim. The balance machine plus visual inspection is all that's needed for a report.

Danny

go to a tire shop and throw it on the speed balance machine.. you will be able to tell easily

[YV1]

You can lift the car, then put an object close to the rim as a point of reference. Now turn the wheel and observe the gap between your reference and the edge of the rim. You will be able to see any bends on the rim.

[E30M3Driver]

A rim can be bent to the point of a noticeable vibration and it not be visible to the naked eye.

The *best* way to tell is on a wheel balance machine which will give you runout readings on the wheel. You can also usually see the wheel "wobble" or "bounce" in its unbalanced state on the machine. Many times a minor bend can be balanced out.

I have bent several wheels unfortunately over my 15 years of BMW experience, and all but one of them have not been visible by just looking at them in a static environment. Even two where I hit a pothole hard enough to turn on the interior lights and emergency flashers were not visibly bent, but were clearly when road driven or tested on a balance machine.

Bent wheels will create a vibration-through the steering wheel if they are on the front or in the seat of the pants if on the rear. A minor bend, because it throws off the balance, may create a vibration that is worse at varying speeds, and at some speeds, may not vibrate at all.

I've never lost air pressure on 10+ bent wheels . . .

A bent wheel should not by itself create a pulling to one side or another. However, the impact that bends a wheel may create a mis-alignment or bent suspension component that creates a pulling.

Whenever buying used wheels, I require a runout report on each wheel or I won't buy them. Only way to guarantee that they are not bent. I also provide the reports on wheels I sell.

[Phat Ham]

Originally Posted by HRC

You can tell if you've bent a rim(s) by loss of air pressure, shimmy at all speeds and if you see an indention on the outside lip.

The inside lip can be bent, too.

[Matt_UKTX]

OK, so the short answer is that if you took them to Discount Tire and asked them to put them on the balancing machine, they would be able to tell for sure, right? I'll just get them to check routinely when I rotate my tires.

Originally Posted by E30M3Driver

A rim can be bent to the point of a noticeable vibration and it not be visible to the naked eye.

The *best* way to tell is on a wheel balance machine which will give you runout readings on the wheel. You can also usually see the wheel "wobble" or "bounce" in its unbalanced state on the machine. Many times a minor bend can be balanced out.

I have bent several wheels unfortunately over my 15 years of BMW experience, and all but one of them have not been visible by just looking at them in a static environment. Even two where I hit a pothole hard enough to turn on the interior lights and emergency flashers were not visibly bent, but were clearly when road driven or tested on a balance machine.

Bent wheels will create a vibration-through the steering wheel if they are on the front or in the seat of the pants if on the rear. A minor bend, because it throws off the balance, may create a vibration that is worse at varying speeds, and at some speeds, may not vibrate at all.

I've never lost air pressure on 10+ bent wheels . . .

A bent wheel should not by itself create a pulling to one side or another. However, the impact that bends a wheel may create a mis-alignment or bent suspension component that creates a pulling.

Whenever buying used wheels, I require a runout report on each wheel or I won't buy them. Only way to guarantee that they are not bent. I also provide the reports on wheels I sell.

[voltron1011]

Good answer E90M3.... I am contemplating buying some used rims in the not so distant future, your info helps a lot.

[lumbergh]

Originally Posted by Phat Ham

The inside lip can be bent, too.

I have two rims with the inside lip bent but look fine on the outside. I have no idea how this happened.