09-13-2008, 06:50 PM
Join Date: Apr 2003
Location: Calgary, Alberta
Originally Posted by RC12
I would just like to ask how you know what rollout to use for this and that motor or is it what rollout for this or that track size?
Sorry for the newbie question, new to 12 scale racing
Thanks in advance!
Pinion Gear = (Rollout x SpurGear=96t) x (TireDia.=47.5 x pi=3.14)
Pinion Gear = (??x96) x (149.15)
Need to know how to get rollout, please...
Using 13.5 Orion Motor
Does the formula above correct?
Thanks again guys!!
Here's what I use for 12th scale roll out
(tire diameter x 3.14) / (spur / pinion) = rollout
or for pinion
(spur x rollout) / (tire size x 3.14) = pinion
so you where very close.
For a 13.5 I would start at 60mm or so
Frantic Racing (Est. 1988)