i got my 10r installed and ran it wed. night with a tekin sc5.5 motor. esc felt like it was really smooth and i had a great time. today i got my viper 4.5xl ordered for a big race next weekend. running it my losi scteon a very big outdoor loamy track. any recomandations on where i should start gearing? i know it will vary and i have several pinion choices, but just want to be in the ball park when i start. thanks