tires bad???

[Beez540]

So the wheels & tires I scored so cheap have been some trouble.

I got the tires holding pressure... leaks fixed, electrolysis spots on the inner rims scrubbed up a bit and the tires are sealed up, proper pressure front & rear.

Wheels are aftermarket (eagle probably?) 16x8. Came off an E28, around a 10 - 12mm offset. They appear to be hubcentric (I see hardly any space between wheel & hub, doubt enough to fit a hubcentric ring). Tires are all 225/50/16zr directional Dunlops.

I get a pretty wicked vibration right around 50mph. It varies depending upon driving conditions... slow accel to 50, cruising downhill at 50 and the vibration is more intense. Hard accel thru 50 and you don't notice it much, cornering at 50 uphill and you don't notice much, cornering downhill 50 and you do.

Also the car wants to shift around bad road grooves more with these tires.

There's some cupping on 2 of the tires, and I started with those in front and it felt like there was more vibration thru the steering wheel, then I put them on the rear and you feel the vibration in the seat more. Also the shifting in and out of road grooves changed to a more rear end oriented shift after putting the cupped tires on the back.

rubbing your hand around the tire you can feel the cups, but I've been trying to scrub them down a lot, and you can't feel it with your hand as much... but the vibration seems the same.

Wheels had evidence of prior force balancing (weights on inside & out). I also had a tire shop just rebalance them yesterday (standard balance only)

IT'S DRIVING ME CRAZY! LITERALLY!

before anyone screams bushings... those were done less than a month ago, pressed in under load, by a great mechanic. And car was feeling perfect with the OEM 15" wheels & tires.

SO, any ideas? could the tires cause that much vibration? What am I missing? Should I just bag these things and start looking for a different set of shoes?

:(

[Beez540]

is everyone as confused as I am?

[Javier]

out of the circle shape. Car got heavy vibrations, also noticed the steering wheel going side to side when very low speed. Balancing will not fix out of shape tires.

Javier

[George Davis]

Yes, it sounds like your tires are bad. Out of round or out of shape tires can mean an internal fault, like belt separation, and such tires tend to blow out sooner rather than later. The cupping is some cause for concern, because that could mean they were run underinflated a lot, which makes them hot, and too much heat causes internal damage. I would replace them immediately, and avoid high speeds until then.

The effects with road grooves aren't necessarily related to bad tires. Wider tires are more affected by grooves, and so are tires with square shoulders. But the cupping seems to be a factor here, too.

[Beez540]

Thanks guys. Time to shop for some 245/50s!

[632 Regal]

245/50? what size rims you runnin?

[Beez540]

Well, I was running 16x8s for about a week. They are now off the car and looking for someone who has time to mess with them. Could be the tires, could be the offset, perhaps they aren't "perfectly" hubcentric (they sure looked like it though). Either way, my car didn't like them or the tires. I think the wear on the tires is really f'ed up... they would wobble ever so slightly when I rolled them across my driveway. Plus, the wheels are so freakin' heavy. So I'm back on the basketweaves... gonna sell this experiment. Next set of wheels & tires I buy are gonna be brand new, put on at a shop, and have a warranty.

[infinity5]

the rims are probaly ok, do they look ok? If you got new quality tires you might just solve all your problems. and a good balance. and a good alignment.. and i assume you've done your thrust arms?

you might not want to toss them out so quickly, at least not if you really like the rims. if you don't, and spending a lot of new rims isn't a big deal, then go for it.... but you're going to have to buy new tires that route as well.



Well, I was running 16x8s for about a week. They are now off the car and looking for someone who has time to mess with them. Could be the tires, could be the offset, perhaps they aren't "perfectly" hubcentric (they sure looked like it though). Either way, my car didn't like them or the tires. I think the wear on the tires is really f'ed up... they would wobble ever so slightly when I rolled them across my driveway. Plus, the wheels are so freakin' heavy. So I'm back on the basketweaves... gonna sell this experiment. Next set of wheels & tires I buy are gonna be brand new, put on at a shop, and have a warranty.

[Paul in NZ]

They appear to be hubcentric (I see hardly any space between wheel & hub
with the wheel on but lugs undone or even all out there should be no up and down or side to side movement,after all the e39-e34 hubcentric rings are only .75 m thick approx 1/32"

[Beez540]

I think the wheels are ok as far as fitment, the tires are pretty buggered. But considering the fact that the wheels are soooo heavy, and the interior portion of the wheel has nasty chrome peeling (which is starting to show on the inner well of the rim, causing tire seal problems). Basically they need some work I'm not interested in dealing with. And... if I'm going to have to put all new tires on them, I may as well start over with a nicer set of wheels.

I'd rather just get something nice, light, clean, and new... my E34 deserves that.

The quest continues, patiently.