Just bought some used rims+tires from someone, put them on my 08 Si, and noticed a slight vibration after 75mph that only gets worse the faster I go. Tires were taken off an 07 Si and recently mounted and balanced. What could be the problem? Do I need to rebalance the wheels? I'm really hoping it's not a bent rim, but would this be fixable?

 

id say rebalance the rims

 

Based on your description, I assume there was NO vibration with your previous wheels and tires. That means that the problem is definitely with the new (used) wheels and tires. It could be any of several things - starting with the most likely cause: 1) the balance on the wheels and tires (which you would find by rebalancing them, which would then fix it), 2) a rim that's bent or out of round (which you could probably also notice when having them balanced, but which you would need to take the wheel to a wheel repair place to fix), or 3) a defective tire (which would need to be replaced but might be under warranty).

 

I'm not running hubcentric rings. Could that be the problem?

 

Yes, if the center bore on your wheels is larger than the hub on your car.

 

How do I find out the hub bore on my wheels? They're 17x7 Super Advan V2s. Bore on the civic is 64.1.

EDIT: Says on this site that they're 73. Does that mean I need the rings?
http://www.yokohamatire.jp/yrc/japan...rv2/index.html

 

Measure it (in millimeters) using a ruler or tape measure. The center bore is the diameter of the big hole in the center of each wheel.

Yes.

 

Where would I purchase hubcentric rings? Could I just stop by any tire store?

 

They might not have them, but you can try.

Other than places that provide them when you buy new wheels, the only place that I've seen them sold is 1010tires.com

 

If the balance is off by 1/4oz, you'll feel it at 70mph. If the balance is off by 1/2oz, you'll feel it by 60mph.

 

Rings didn't fix it, but rebalancing it did. Thanks for the help guys!