I got a TC4 Factory Team Car and a velocity 5.5R and a GTB. I started with the guided gear ratio 72 and a 20 and I have a SCREAMING hot motor, speed control and batteries. I upped gears to a 69 tooth spur and 33 tooth pinion. Motor & speed controller ice cold, batteries very hot. B4 I couldn't touch the whole car b/c the whole car was hot. Now I just can't touch the batteries (Batteries are 3800 intellect matched professional with NovaK gold bars and sermos (?) connectors - I know their not deanes or tamiya)....any ideas?????

The only thing I can come up with is that maybe you have drag/binding in the driveline somewhere. If not try gearing lower (higher ratio) than the 20/72 recommended and see what happens. If problems still exist then system may be at fault.

Good luck. :)

the higher i gear it the cooler it gets and i found the terminal velocity, 78 mph. I am running on street 50 yard drag race, hairpin, 50 yard drag race you get the idea. no binding, without a motor car won't sit on a flat table.

oh and the lower i gear the hotter it gets i've tried

pps I have the same problem in my pro4. different motor different speed control. i ran a 5800 and a ss before with no problems. does a 5.5v draw that much more amps?

The 5.5 will draw more current (a lot more) and the batteries can get really hot if you run them until they dump with a big gear.

if i run a 5800s will that fix the problem

Yes, more powerful motor = more heat plain and simple