Originally Posted by
fq06
With different sidewall profiles and tire widths, how do they get so exact?
All I've ever seen is a box to measure and frankly there is enough flex in the wheel, tire, hub and so on to get a truck through that's a few mm's off.
Do they have a set of rims that they mount up to racers trucks to take the measurement? Really makes no difference to me, haven't attended a roar race in a year and a half... just curious how they are measuring the width.
I wouldn't want to be too far past if at all, I do want to keep the race fair. I think the traxxas mod will be within reason for any club race but looking forward to hearing an actual on truck measurement.
It's supposed to be a box that your truck can roll freely through in ready-to-run form (IE: body on). So yea, the sidewalls and wheels come into play, but in the end it's the measurement on widest part of the truck because the box's walls should be cut to the maximum width.
Since the measurement isn't at the end of the wheel hex (it's the widest point of the tire), you have to add a few MM considering that the bottom of the tire sticks out if running negative camber.
So if you're very close, some last second minor camber adjustments will get you though.