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View Full Version : Wheel Balance And Runout Tolerences



BRIAN
09-02-2004, 06:41 PM
Was happy to get new rims today until I saw one had slight bend at lip. Not wanting to wait for new one to be made I took out dial indicator and mounted wheel to verify runout and determine extent of damages. WOW!! I have never actually measured a rim before and was a little shocked to see .035 or so even on one of the other none damged wheels. This is a total variance up and down.
I checked an OEM cast Ford rim and got .010. Both rims had about the same at the wheel bead which was approx .005.
Considering that most wheel Co's use the same hoops has anybody else done measuring or had some wheel balancing issues. I know lip is not as important as bead but???
Anybody have measurements. I am satisfied with rim repair which only took one blow from a nylon hammer to pop back where bead is unaffected and lip is back into round. I am just curious as I do not have any other rims laying around to check. The dial indicator is set on the top of the edge of the bead NOT measuring as you would with a rotor. The rim did not have face ding but TOP down towards hub. Thanks. I am calling MFG tomorrow to verify tolerences.

dennis68
09-02-2004, 08:48 PM
My Centerlines and Falken combo fails the runout test miserably. Most wheels will show quite a bit, production line work.We use the new Hunter DSP machine, very nice equipment. It will measure the wheel/tire combo and show exactly where the high/low spots are. Basicall a runout gauge built in the machine.

workbenchracer
09-03-2004, 02:02 PM
.035 isn't bad. What you need to worry about is the radial harmonics mainly the 1st. These are calculated from measurements taken around the wheel. 1st meaning one time per revolution. There is also 2nd and so forth. What these can do is obviously give a bad ride but also get things to resonate in the car. I have a program at work that can calculate these for you if you want. It's not a difficult thing to write but since it is my work's "property" I can't give it out. Give me atleast 10 measurements (the more the better) taken at equal intervals from around both bead flanges. Start at the valve stem and go in a clockwise direction. Make sure your runout gage goes back to zero when you get back to the valve stem.