Measuring Rim runout

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Hey folks I was wondering if some one with machinist inclinations and knowledge could help me out. Went to measure my 10 year old ford focus rims.
I set the rim on a no-mar wheel balancer and locked it in with 2 polyurethane cones.
Here are some pictures:
instagram.com/p/8g4vBcMvED
instagram.com/p/8g42QysvEN

Now the dial indicator told me that I have 0.7 inches of radial runout. When I turn the wheel by hand even slowly I can see the lip that I measured wobbling and wondering.
But still 0.7 inches of runout sounds a lot did I measure it right? Or would having it on a tire balancer introduce errors?
 
These are 10 year old rims driven it Pot-Holia err Buffalo, trust me almost an inch of run out is not factory spec
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As the rim increases in diameter, the value of runout can increase with no increase of amplitude. Is there not a formula for this?
 
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Originally Posted By: Rust_Belt_Pete
correction I am an idiot who cant read dial indicators its off by 0.075 which is still too much
I used a mic etc at work not like a machinist would but I would really have to check and double check and sometimes ask the parts girl if I read the instrument correctly.
 
.075 dosnt sound like much on a automotive wheel. Make sure wheel is zero'd good on that shaft. Couldnt tell you what the spec should be. Are you touching off on the face or the diameter?

Trash that harbor freight mag base and get a NOGA !
 
I am measuring on the lip, the bead seat still has crud on it and I would get a bad reading. I had about 0.095 of lateral runout too.

Checked the rest of my rims the are either as bad or worse.
The car that these were on almost ate through 3/4 of the tread on a set of Pirelli P4's in 15k miles, shocks and struts were replaced 20k miles ago and I had done an alignment and a balance before having the tires mounted.
 
Originally Posted By: Miller88
Did the car shake at all with that much runout?


Yeah, the front especially. Had to replace both rear bearings recently too, could have been related to that. (I did tow a 600 pound trailer with the car for 400 miles total at one point though, but dont think 400 miles towing 600 pounds would make that much difference)
It would shake around 45 but went away at 60ish mph
 
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Ok I dropped the ball on the measurments. I set the 0 wrong and forgot that the dial travels both ways so the actual variation in runout is double what I measured. 0.15 inches
 
Originally Posted By: Rust_Belt_Pete
Originally Posted By: Miller88
Did the car shake at all with that much runout?


Yeah, the front especially. Had to replace both rear bearings recently too, could have been related to that. (I did tow a 600 pound trailer with the car for 400 miles total at one point though, but dont think 400 miles towing 600 pounds would make that much difference)
It would shake around 45 but went away at 60ish mph


What year Focus? I have probably 500 miles towing my popup (850 dry, 1000 or so loaded) without any shaking issues or anything else.
 
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