[Teeman]

Had my 330I, with the Bridgestone Potenza's that come with the Sport Package, out on the highway today. At a speed higher than 70 I noticed that the ride got a little bumpy. I wasn't sure if some balancing of the wheels was in order, or if this is just the feel from the performance run flats. Does anyone know if at higher speeds with these tires do you get a slight rough ride?

[Kao BMW]

I've noticed that the runflats (due to its steel wall casing) has a bumpier ride than normal tires.

[itznin]

Originally Posted by Teeman

Had my 330I, with the Bridgestone Potenza's that come with the Sport Package, out on the highway today. At a speed higher than 70 I noticed that the ride got a little bumpy. I wasn't sure if some balancing of the wheels was in order, or if this is just the feel from the performance run flats. Does anyone know if at higher speeds with these tires do you get a slight rough ride?

In case you haven't checked already, check your tire pressure (when the car is cold) and make sure the PSI is correct.

[silverado]

It is interesting that you're describing the ride as "bumpy" while going at 70 mph on a highway. Did the road have bumps?

I would second the suggestion of checking your tire pressure (you probably want the < 100 mph setting with 4 passengers from the manual). My tires were over-inflated and the ride improved noticeably after I corrected the pressure.

[Teeman]

No the road was smooth, and I had to correct the tire pressure after picking it up from the dealer some weeks ago. They are fine. It just felt like there was a flat spot on one of the tires, not that I think that's the problem, or wheel balancing was needed. But to be honest, the steering wheel was not visibly shaking.

[res_ipsa]

But even if the steering wheel wasn't shaking, the ride still shouldn't feel bumpy. Was it like a consistent bumpiness? Like you'd feel the bump on every rotation of the wheel? Or was it more random? If it was random then it's probably just the road irregularities, but if it was like a consistent bumpiness then maybe your wheels need balancing or something.

[Teeman]

It was consistent. The road is pretty smooth. I'm going to tell the dealer about it the next chance I get. It wasn't terrible, but it wasn't as smooth as I would expect.

[onesixeight]

I thought my ZSP car was pretty bumpy after picking it up, but after putting some mileage on the car, the ride seems to be getting a lot better. I have a E60 530i ZSP with Run-Flats and the ride seems to get better with age!

My E90 had balance problems and they rebalanced all four tires free of charge. My alignment was also off and veering to the right. Have your dealer look at your car as soon as possible since alignment and balance issues are only covered for the first 2 months or 2000 miles.

-Chris

[PhilS]

Originally Posted by Teeman

Had my 330I, with the Bridgestone Potenza's that come with the Sport Package, out on the highway today. At a speed higher than 70 I noticed that the ride got a little bumpy. I wasn't sure if some balancing of the wheels was in order, or if this is just the feel from the performance run flats. Does anyone know if at higher speeds with these tires do you get a slight rough ride?

I had a similar problem in the past with an E60. From memory it was actually worse when driving the car first thing morning and lessened as the tyres warmed up.

In my case, the dealer tried various things including re-balancing several times with no success. He eventually ended up swopping the wheels and tyres with a spare set they had in stock. Everything was OK from then on.

Trying out another set of wheels and tyres is a good place to start.

A couple of other things worth considering:

1. A tyre or tyres are incorrectly seated. Your dealer should be able to fix this by breaking the seal on the tyre and re-inflating.

2. It could also be a flat spot on a tyre/tyres.

[Spaceman]

Originally Posted by itznin

In case you haven't checked already, check your tire pressure (when the car is cold) and make sure the PSI is correct.

This may not be your case Teeman, but this is an oh so important detail. I have been experiencing quite a few bumps and attributed it to new suspensions /wheels/ break ins syndrome. But after reading at this forums regarding how car tire pressures are elevated prior to shipping and that dealers are supposed to correct them before releasing, I decided to check it out, and found out that instead of Front 29PSI, rear 35PSI, The car tires were at 36PSI all the way round. I bled off the excess and the ride is 10X smoother...