That's called the Spur gear. If you want less bottom end and more top end, I believe you have to get a smaller spur gear and adjust your motor upward. You can also get a larger pinion gear at the same time.
Im shopping for a replacement main gear because mine is starting to show wear. Actually let me back track for a sec, Im not sure if its really called the "main gear" but here is the setup: (Its a RC18t BTW, 4WD with shaft driven front & rear diffs). Its the shaft gear Im talking about. First you have the motor and it has a small gear on it, which in turn drives a larger gear, which is attached to the main driveshaft. That larger gear is the one I am replacing.
I think stock is 56 or 57 tooth. Ive seen replacements go up to 60. Now as it stands now, my truck can easily wheelie off the line, so perhaps off the line speed isn't what Im going for. What I would rather have is low end torque to climb hills or obstacles. I have a feeling that goes against what I initially said about "wheeling off the line..." but if thats what I need, then I'll just learn to live with it or if I can adjust the ESC to be more "gentle" then Ill do that...
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