Originally Posted by MK_Arbiter
What tooth pinion should I use if I'm using a 10T motor and a 105 tooth spur?
IMO, for a track with long straights - 10turn handwound Mods - timing advance at conservative level, I might select between 7.88 - 7.16 ratios (30t to 33t pinions on 105 spur) should be ok.
It very much depends on your Motor Revs and Batteries' punch.
For me, I would gear it to such that the motor achieves its highest possible revs (by listening to the motor scream) by the end of the straights just before the point where I would normally lift off throttle to prepare for corner entry.
Just my 2cents, Cheers & Merry Christmas
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