Measuring tread width?

[Knotty Racing]

Is there a description on how to measure the tread width?

Is it from the outside with the letters or just the tread portion from the decorative edge?

Trying to figure out if I have any wheels that are BASX legal for my son to run.

Thanks.

 

[quadad]

I have never seen a real definition, but I believe it is the actual, useful width of the tread that will touch the running surface. It is NOT the width of the wheel. When I measure like this on a few wheels, the numbers make sense (i.e. close to the specs for that particular wheel).

 

[Kinser Racing]

...I believe it is the actual, useful width of the tread that will touch the running surface. It is NOT the width of the wheel.

+1

 

[cycrunner]

The rules that I have read for the BSA wheels is the measurement is from the outer part of the little bumps on the outer part of the wheel. It is not the width of the flat tread that contacts the track. If you measure only over the flat you may be too narrow.

 

[B_Regal Racing]

I measured a few stock wheels I had laying around a while ago and had an average tread width of .305 inches. That is the actual tread surface that contacts the track, not including the fluting on the outer edge or the rounded inside edge. This translates as 7.747mm, which would be less that 8mm for the BASX class, but since they are stock BSA wheels, I'm sure I'm measuring it from the wrong points on the wheel. My BASX entry will have stock wheels with only a wheel bore treatment, just too be safe.

 

[Knotty Racing]

Some stock wheels are pretty nasty and are heavier than the 2.4 g min, so stock can come off somewhere - OD for sure as described in rules.

Maybe a better question then is....Is the inside tread edge able to be trued at all for the BASX class and still meet the minimum tread width?

Maybe John will chime in with how the tread width will be measured.

 

[Guest]

I really wish someone would post a glossary of terms