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ok, I am back to a heat problem. I have tackled everything I could think of and you guys directed me too.

I swapped in deans connectors
rebuilt the 6 gear tranny
new battery (lipo)
I put a 27T motor in with the original pinion and spur gears

The motor is still getting hot, BUT.... the car is rockin'!

electric motors get hot........ it's what they do. so when you say it's hot, exactly how hot is it?

i used to gear the living piss out of my cars (back when i raced weekly) that you couldn't get anywhere near it after a 4 minute run. they still run just as good today as they did 20 years ago.

This thread needs to go in the tech section Scr8p

what?

Good to know. It is hot fast, too hot too touch but if that is normal then sweet!

Take one of the brushes out and look at the commutator. If it is discolored with red and pink, and it has a ton of black leading away from each separation (there's 3 splits in the comm) it's over geared. A little black is normal, but too much is an indicator of excessive load.

I am over geared... the motor was smoking today. That cannot be a good sign.

You do let it could down between runs right?lol Best thing is to run a heatsink to make your motor last longer,or vent the body to let air get back there to the motor,it surely helps.Don

quick question i didn't think about asking yesterday.....

when you say "original spur/pinion", is that from the kit or what was on it when you got the car?

It is the gears that came with the kit. I figured it would be good since the motor with the kit is 27T and the motor I just dropped in is 27T

Recommendations on where to go from here as far as gearing?

I did not think tire size would matter since I used to swap between truck wheels and buggy wheels back in the day without changing anything else without any noticeable problems.

what motor are you running?
what gearing do you currently have?
what surface are you running on?
what are you doing with the car, racing or bashing?
how long are you running the car?
what tranny are you using? The 6 gear you rebuilt or the stealth in the car you just scored?

JHarris wrote:what motor are you running?
what gearing do you currently have?
what surface are you running on?
what are you doing with the car, racing or bashing?
how long are you running the car?
what tranny are you using? The 6 gear you rebuilt or the stealth in the car you just scored?

27T stock motor
grass, street and anything in between
bashing
a complete battery
6gear

27T stock motor

24 or 36 degree?

grass, street and anything in between

There's part of your problem. Grass puts an incredible amount of stress on the car and electronics. I'm all for running all over the place, but try to avoid the grass. Nothing good will ever come from it.

bashing

Just be sure to let go of the throttle when the car is stuck or up against a fixed object.

a complete battery

If you are running until it dumps, that's not helping. If your battery will run 20 minutes, set a timer for 15. Make sure you don't take one battery out and throw another in only to fire it right back up, essentially turning the run into a continuous hour long session. That will lead to costly repairs and replacements. If you want to run long term, grab a few spare motors and swap the motor when you change batteries. It only takes 5 minutes to change the motor and will give you an opportunity to look the car over to be sure there's no grass wrapped around the dog bones or other moving parts.

6gear

What pinion/spur?


You mentioned something about truck tires. If you are running truck tires but are geared for buggy tires, it will cause you problems. You need to drop at least 2 or 3 teeth on your pinion for the larger tires. Remember, it's better to under gear and sneak up on the optimal gearing than to over do it and burn up motors, speed controllers and batteries.

Just changed to a 15 and 83 on the street and it was crawling and it smoked again. Motor must have been shot anyway

With that final drive ratio (FDR) you should have been fine. Double check the car, esc, battery and radio settings. Swap motors and run it again, this time only on hard surfaces and see what happens.