KF2 Gearing
 

Hi what would be a reasonable gear ration pin to spur for a 10.5 motor running on Astro with a fairly long straight. Have a Speed Passion Reventon Pro Speed Controller in a brand new KF2 SE. Thanks.

Ideally you'd want a final drive ratio of 6.5 if using a 10.5t motor
So spur divided by pinion times internal ratio(2.58), will give you your FDR.
Check the manual for possible combinations to achieve this.

We ran our kf2's on 28/83 (mine with 50% boost) on a 8.5t speed passion and sp pro. My son ran 29/83 on a 10.5t with reventon r no boost. Both on bumpy astro at rhr. Both worked really well.

KF2 gearing
 

Would 27/76T be ok with a circuit with long straight but twisty infield running standard mod 0 profilr on speed passion pro ?

I run 24/76 with a 6.5T with some boost and turbo mixed in for good measure :)

So 27/76 T would be ok using standard MOD O profile on a 10.5T. Am not used to all this technology with adjustable things on speed controllers