danglerb

I am getting a bit of vibration, enough to make it hard to ID cop cars in the rear view mirror about 85 MPH, its gone below 80, gets better or different over 90, but its gotta go. Any tips on getting the wheels balanced, 83 anodized factory slots, guessing 16x7 front and rear, 3k miles, but two year old Kumho 225/50 from Discount Tire Center. I am wondering given the 3000 miles and 18 months if I should have the tires balance checked, ie if its good the vibration is from something else.

I know of good local shops, but a national chain with a lifetime balance might temp me. Mostly looking for those two sentences of instruction all Porsche owners give to tire guys.

Charley B

3k miles, but two year old Kumho 225/50 - Quoted by Dan Glerb

Flat spots.

chaadster

Discount Tire has their Road Force balance machine that applies load to the wheel and allows, it is claimed, more accurate balancing.

I had some bothersome vibrations after mounting Kumho MXs, and the RoadForce balancing dealt with it pretty well, though not completely.

I wonder if the Kumhos might have inconsistencies in the casing/tread? Dunno. I guess it could be the wheels are out of round, because I haven't checked that.

Good luck, anyway.

danglerb

In the past I have had a couple drawn out tire balance adventures, and there isn't freaking anything that can't be wrong. Years ago on my 914 it had vibration just over 55 mph, and I tried everything, finally Greg was replacing the half shafts and found an extra ball bearing out of the CV joint loose in the grease inside the boot.

Really good local references in this thread, so I think I will just pick one.
https://rennlist.com/forums/928-forum/318997-socal-oc-tire-shops.html