at 80mph i didnt notice any vibration, but at 100mph i notice a slight vibration which i thought was the wheels.
The steering wheel is fine....

i just had the wheels balanced and rotated.
my car has 40,000 miles already, is an alignment needed?
(car DOES NOT veer to the right or to the left)

what could cause that vibration at 100mph?
what can be done to correct it?

my suspension is stock, i have a 15x7 aftermarket wheels

the vibration IS NOT STRONG, i would say a "SLIGHT vibration"
there is NO sound or anything underneath

is that NORMAL when you hit 100mph?

 

I have the same issue in my 2007 GD Fit at about 80 mph. The previous owner had painted the calipers and drums bright red, but he didn't tape the mating section of the wheel. I was told this might cause a slight unbalance, and be the source of the vibrations at highway speeds.

 

Do your aftermarket wheels require "Hub Centric Rings?"

 

i dont think i needs it...?
my wheels are Enkei RPF-1, 15x7, (tires are kumho ecsta 195/55)

maybe i need to have the wheels and tires Re-Balance?

 

yes, balance check them and prolly rotate them too.

I've gone in the 100mph and over on the fit, have not had issue with vibration and I don't have hub centric rings either.

 

maybe check for bends.. even small ones can cause vibration

 

Are you using the correct type of lug nuts on your RPF-1s? After listening to the tire/wheel guys that I deal with, I learned that some lug nuts for my RPF-1s seat better than others. The tuner lugs that I originally wanted, weren't a good fit. So, I had to look for a different set.
If you decide to go without hub centric rings, at least make sure your choice of lug nuts are a good match. Also, if you go "lug centric" they say to tighten the lugs with the wheels off the ground.

Here is a discussion about using "hub centric rings." Maybe this might help you solve your vibrating wheel problem.
Hubcentric rings. Are they truly necessary?: Grassroots Motorsports forum: Grassroots Motorsports Magazine

 

Most balancers don't spin the wheels fast enough to catch variations in balance at 80 mph. Maybe try another place and let them know the problem you are having.

Or find a place that balances the wheel, hub, and rotor as one unit while on the car. The only drawback is that you will need to keep that wheel in that position every time you take off a wheel.

 

Likely a slightly off balance wheel at that speed. Most local shops that I have been too seem to end up with one tire (at least) slightly off balance, that will only show at higher speeds. (Right now I have a vibration that shows up around 70mph, but I am running studded snows, so shouldn't be going too much faster anyway.)

 

WELL THERE"S YER PROBLEM!!! :P

That's 15mph over the highest speed limit anywhere in America and 35 over the typical 65. You're asking the wrong question. The right question is, "Am I simultaneously foolhardy and selfish to drive so fast on public roads," and the answer is yes.

If you're looking for a semi-technical reason to stop doing it, I'll gently point out that a BMW (any of them) is designed to be controllable and reasonably safe at 125mph, assuming the road is well-maintained. The Japanese rarely drive over 100kph, and I've rarely encountered highways in America a German would consider well-maintained. So stop doing it in the Fit.

 

i am using the oem lugnuts...
probably gonna have my wheels rebalanced
at 100mph the fit is very stable/controllable, wanted to go more than that had that slight vibration not happened

 

I am not sure what type of lugnuts your OEM lugs are, but here in US, our's are of the "ball seat" type. The RPF1s that I have require a "cone seat" type lugnut to achieve the most seat area. Also, there is a chance that your OEM lugnuts are not fully seating. Anyway, take a look at this link:

Can I use original lug nuts for custom whees?

 

the ones i am using are the ones that came from the factory for my
rpf-1, 15x7...do i need to buy aftermarket lugnuts for the rpf?
if this is a safety issue, what are the good aftermarket ones that will
fit the rpf's best?

thanks

 

No on has said a bad tire yet.
- although 2 of you have the problem.
-- but, if ONLY 2 of you have the problem... ...although not everyone is going to go 100mph to find out...

GL

 

I don't have to go 100 mph in "My Fit". I will take your word, that it will go 100 mph. Thanks for the information. Foyd Boat.