Tire replacement time is an opportunity to check the condition of the wheels.
Aside from addressing appearance issues, the radial (hop) and lateral (wobble) dimensions can be checked when the tire is off the wheel.
A free-wheeling front hub provides a convenient "machine" to rotate the wheel and to set-up a dial indicator.
The hub must be clean and true for our "test machine" to provide reliable measurements.
Assuming that is the case, what are reasonable values?
Jaguar service manuals have not yielded a clue (that I have found).
"General" guidance for alloy wheels found on the web says that 30-thousandths of an inch (0.030") is acceptable.
That is understood to be the maximum allowable radial or lateral movement from a perfectly "true" running wheel.
I have no brand-new wheels, but the 18" Vela wheels that I have checked, run from 5-thousandths to 35-thousandths.
Surprisingly, the best results, thus far, have been on 9.5" wide wheels. These have the largest span from web to bead and, I thought, the greatest likelihood of error.
So, my question is: what is the best (minimum) radial and lateral deflections that we might reasonably find on new or properly refurbished wheels?
Note: wheel refinishers typically say that they meet or exceed the "manufacturer's criteria" of 30-thousandths of an inch.
Note also: 1/32" = 0.03125", so 30-thousandths is just a little less than 1/32".


Typical information from a tire manufacturer. Actual wheel measurements should be where the tire contacts the wheel.
That is, the dial indicator should be on the opposite side of the metal - on the bead surface.

 

Nine Vela wheels were mounted as previously described. Runout in inches was measured using a dial-indicator gauge.



The purpose of this exercise is two-fold:
1. Evaluate the wheels for actual use.
2. Understand typical run-out values for a range of used alloy wheels.

Measurements were done twice to confirm reliability.
All wheels were used. The amount of use tended to correlate with amount of run-out.
Measurements were taken in the middle of the respective bead surface for both Lateral and Radial.

Conclusions:
Wheel F3 has the best (lowest) overall runout ranging from 0.002" to 0.005" It shows very little use.
It appears that the OEM specifies Run-out values between 0.000" and .005".
What is not evident from the values is the presentation of variation. Some variations change slowly and some change twice in one rotation.
An apparent dent is seen as a quick deviation over a short distance.
F1 and F3 were selected for front wheels.
R2 and R4 were selected for rear wheels.