RAudi Driver

Ok, so the car has been dialed in and I still have this slight vibration at 75 MPH. I called my tire guy and he assured me that my BBS E88's balanced out perfectly. He said that they came out real nice without having to use a lot of weights. I have them balanced on a Hunter 9700.

That being said, I'm wondering if my rotors could be playing a part in this vibration as I recently read this on one of these forums.

Any insight is really appreciated.

https://rennlist.com/forums/928-foru...mps-75mph.html

Doc GTO

What tires and how often do you drive the car? If certain tires sit a while, it may take some miles and heat to round them out again. Did they road force balance them?

tcsracing1

tires may have flat spots?

RAudi Driver

That's what I'm thinking. I running 19" E88's with Super Sports. The car sits like there is no tomorrow. I manage to get it out maybe once a week for about 25 miles. I'm trying to get it out to the track and just drive it more but just don't have the free time.

How much driving does it take to rid the tire of it's flat spots?

Richie18

I have the MPSC and I have driven my car after prolong periods of storage and have not a flat spotting type of issue. I doubt the Super Sports are flat spotting.

Also if you if the car sat like there is no tomorrow wouldn't it not be sitting very much?!

RAudi Driver

Lol, good to know. I had the vibration with the OEM wheels and RE11's also. That's why I'm wondering if it could be the rotors. I would never think that the rotors could be a culprit but after reading that one post in my linked thread, I'm wondering.

I'll take the car out today for a run through Angelus Crest and see what happens.

ChrisF

Are you feeling the vibration in all wheels? Are you feeling it through the pedal on hard stops? Maybe try a few 80-20 stops on an empty road to see if you are getting a more pronounced vibration. How many miles on the car? Wouldn't think wheel bearings unless the car had very high miles.

If it really bugs you and you aren't able to solve it yourself, you have a great shop close by (Werks II) that I'm sure could help.

RAudi Driver

The vibration is only in the front. The car has 27k on it. The brake pedal is smooth as silk.

Getting dragged out of the house to get the kid some clothes. I'll be back later.

DC640

Just came back from Angeles Crest bike ride hot day and i couldnt climb as well.

i have flat spots on my car (P Corsa) and it does vibrate from 60+. Indeed it is annoying. I do agree with your logic that it probably cant be your tires since you had this symptom with other tires. But can it be really your rotors?

skxf430

How long are you guys parking your cars to get flat spots?

I have never had that issue and had my car sit for over several weeks at a time.

DC640

I got mine from a hot scorching track day. Just melted my tires when the car was "cooking" on asphalt bt runs.

RAudi: is it a slight vibration or would you say the steering wheel wiggles left and right?

skxf430

Interesting. Been to many days at Willow and Buttonwillow when temps are well into the 100's and no flat spots.

senna

I had the same problem with SS tires. Someone here said he called Michelin and got a new set. Mine was fine after driving 300 miles or so and balancing each wheel again. Not sure if that makes sense. I also run my tires around 32psi rear and 29 psi front cold.

mdrums

Takes my car about 30 miles in hot weather to smooth out if it has sat for a week or so

RAudi Driver

Ok, I'm going to blast through these tires and then get something different. I'll have my tire guy rebalance them tomorrow (roadforce) and report back.

The vibration is quite noticable. It actually moves the wheel left to right and can be seen from a passing car.