Bent Rim on Inside

[Infinity1911]

Hey folks,

First time posting here, and I’m happy to be a part of this forum.

2017 BMW M240i Convertible

All too-familiar story ahead:

Yesterday, I hit a pothole - a small one that was quite deep. I made it into work, about 30 minutes away thinking everything was okay. At lunchtime, I observed a drop in tire pressure, down to 17PSI. This is the front passenger tire.

I very slowly made my way to a local Express Oil / Tire Engineers place, where the mechanic said my tire was toast. He gave me enough for me to hobble down to NTB.

Got to NTB, and they fortunately had the same tire in stock. About an hour or so later, I’m getting ready to check out, and they inform me that there’s a big oblong bend on the inside of the rim. They said it will not hurt the life of the tire, is safe, and for me to replace it only if it bothers me. It also does not interfere with how the tire fits. You can’t see it from the outside.

They took it for a test drive, and said that I might feel some vibration at 40+ MPH.

They strongly suggested that I hold off on buying a new rim right away until I see for myself how bad the vibrations are.

On my way home, I tried to test different speeds. This is Alabama, and we have awful roads, so it’s hard for me to say. But, I got some space on the interstate and got it up to 95. Again, hard for me to say. Our interstates are just as bad as our backroads.

I did get a fresh alignment, which helped immensely - something that was necessary after hitting such a large hole.

Took it out for lunch today, dropped the top, and I still couldn’t hear or feel much, EXCEPT for a slight vibration in the steering wheel and seat. But I couldn’t tell if it was originating from the front right rim.

Thoughts, comments? I will replace it if it gets worse. But again, with our roads the way they are, I feel like I’m always going to be replacing a rim.

Thanks!
-Infinity1911

[DennisCooper]

Hi,

You can have the wheel buckle/bend fixed at a reputable wheel refinishing place that's able to do the job. It'll never be 100% but will be quite close and to the extent you'd probably not feel it even on a nice smooth stretch of road.

That's what I'd do personally.

If you are worried it'll happen again and all you ever drive on is really bad potholed roads, then you could change down an inch or two inch in wheel sizes and then use larger profile tyres that match the OEM rolling radius. This way, you'll get a softer ride, and when you go over the very bad roads you use all the time, there'll be more 'cushioning' by the larger tyre sidewalls which hopefully prevent more bends on the wheels. Another alternative is to change to non run flat tyres. If your M240i is running on OEM run flat tyres, then these have much stiffer tyre sidewalls. This is so that when punctured, you can still drive on them to get them changed instead of jacking the car up and changing to a spare. Those much stiffer sidewalls 'transfer' the energy of a shock of going over a pothole straight to the wheel itself and on large enough potholes and the forces exerted, you get the common aspect of a bend in the wheel. Change to the same size/profile non run flat tyres and they have a softer sidewall in direct comparison.

Cheers, Dennis!

[Carpy2]

Hi,

You can have the wheel buckle/bend fixed at a reputable wheel refinishing place that's able to do the job. It'll never be 100% but will be quite close and to the extent you'd probably not feel it even on a nice smooth stretch of road.

That's what I'd do personally.

Cheers, Dennis!

+1. Have had multiple track wheels fixed by local rim repair shops. Experience no vibrations at high speeds. It's pretty crazy how bent a wheel can be, but still be fixable. If they quote you too close to the cost of a new one, then get a new one. But if it's half the cost of a new one, you can go ahead and bend another one

[MarcoZandrini]

Bimmers are pretty sensitive to issues with tires (balance, air pressure, damage) and rims (damage). I recommend you take Dennis’ advice and have the rim fixed. Are you running a staggered set up? If not, have the rim fixed and mount it on the rear.