I went to a 21T pinion last night. Not that this truck needed it...but wow, what a difference in the top end!

One note for current SBR owners...someone got red loctite happy with pinion set screw on my rig. Typical stuff here...use a soldering pencil on the set screw set to high heat. Give it a few minutes and take it off. Even doing this way...I had to use a small pry bar to eject the pinion. The loctite was so heavy that it was on the motor shaft and it collected/globed under set screw threads.

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