80+ mph vibration
Just installed my new 19" Forgestar CF5s with hub centric rings, straight from the manufacturer through ACG for mount/balance. 8.5" wide front, 10" back. Tires are Hankook v12 245/35 front, 275/30 rear. OEM suspension. Lug bolts are conical to match the wheels and torqued to 100lbs each. Test drove after install and noticed a good bit of steering wheel vibration going on after 80 mph. Definitely didn't exist when I was running OEM wheels on blizzak 235/40/18 at all four corners.
1) So I'm thinking wheel balance? I checked out the wheel weights and none seem to be missing from shipping. Front wheels have 2-3 1/4 oz weights, rear right has 5 1/4 oz weights (balanced between inside and outside of the rim) and the fourth (rear left) has 9 weights on the outside and 3 on the inside. I know ACG has a hunter machine so this seems a bit out of the ordinary? Could this cause vibration at high speeds...odd that it would be in the steering wheel though?
2) Bent wheel? Anyone ever seen a wheel bent from shipping??
3) Bad / warped tire?
4) Alignment? (low probability)
How would you suggest I diagnose this issue? Clearly I'm going to wait on ACG to get back to me but many times I've seen some of these detailed issues have a very simple answer...
If they have a hunter machine they sure dont know how to use it find a good shop with it and get rebalanced !
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What is slightly interesting is that many tire centers have a memo that says to torque them to 86 lb ft using thin wall yellow lug nut adapters for the air torque drivers.
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They don't sell "seconds" however some Distributors sell returned tires a second time or third.
They could be out of round or lumpy and all the balance weights, in the world, won't make them ride right.
Usually the car Dealer will have the first picks but don't count on it.
Take it back until they balance perfect not a quarter of half ounce off.
Road Force Balancers can get many tires to ride smooth.
The wheels, you have, I'm not familiar with.
When you have them rebalanced watch them spin.
The Dealer, that sold you the tires wants satisfied Customers , hopefully.
He should want to find the problems for you.
When you buy new wheels and they are already balanced... they need to be rebalanced to your own tyres. Or rebalanced to the tyres you're going to put on the car.
So once your wheels arrive, you need to take them to a tyre shop, get them to mount the tyres onto the wheels then balance them.
Also if the wheels are aftermarket they must use hub rings. Mercedes is usually 73.1 - 66.6 and if they are mercedes replica wheels you will not need hub rings.
Hope this helps
Unless you go to a machine shop that can make you an exact set of rings / sleeves machined from aluminum and (permanently) pressed in the hub bore of the wheels, your only option at this point is to keep taking the wheels off and putting them back on until you hopefully end up centering them somewhat better than the first time.
Everything else is a generic center bore so they supply the rings per application.
Agree with you that it's not optimal, but it's how they offer the product at this price unfortunately.
Kirk, can you verify you cleaned the hubs as well before putting the wheels on?
Keep me posted.
Everything else is a generic center bore so they supply the rings per application.
Agree with you that it's not optimal, but it's how they offer the product at this price unfortunately.
Kirk, can you verify you cleaned the hubs as well before putting the wheels on?
Keep me posted.
1. Check the hubs to make sure they're clean as Tal suggests. I'm going to pull off the wheels and wire brush them; I didn't do that when I mounted them originally.
2. Recheck that the rings are the right size; I didn't check the stamps on them, but would assume I would've seen the misaligned lug holes in the rotor / wheel.
3. Get an alignment; am I just noticing the toe-in drag more with more surface contact and wider tires? It also felt this morning like the vibration may have been less or gone when taking a sweeping left turn. Maybe a slight pull to the left as well?

There are a number of pre-made rings that you can buy from http://www.1010tires.com/store/0mm.-...-4)-60632.aspx. Inner bore that you'll need is 66.56 mm - and maybe someone else (Tal?) can chime in with the center bore size of the Forgestars.
Last edited by Diabolis; Apr 23, 2014 at 07:08 PM.
2) Bent wheel? Anyone ever seen a wheel bent from shipping??
3) Bad / warped tire?
4) Alignment? (low probability)
How would you suggest I diagnose this issue? Clearly I'm going to wait on ACG to get back to me but many times I've seen some of these detailed issues have a very simple answer...
Hub before photo:

Hub after photo:

Should I have the rear tires rotated, e.g. 90 or 180, on the wheel and road force balanced to remove some of the weight? Each has about 2-3 ozs of weights now.












