Burning up motors
 

I got a old Rc for my son, running a brushed 20t motor. I put my 5000mah, 2s lipo on and it burnt the motor up. I then put a 5000mah, nimh, 7.2v with a new 20t motor and it burnt up the motor also. I don't know what spur is on the car, since it's an vintage RC10T I had laying around. Could the battery be too much, or should I buy new gears to see if that's the issue? I'm running brushless on mine and it's way too fast for him until he gets some experience. So I'm trying to keep his car cheaper and slower for now.

Won't be the battery(s)

Will almost definitely be a gearing issue.

What pinion and spur combination?

Check the drive train and make sure you don't have any binding.

Brushed and brushless motors generally need very different gearing. Make sure you're using an appropriate ratio for the motor.

Yes, check the drive train maybe that is the problem

Gearing or a bind, take the pinion off and make sure you can roll the tires freely as on a rc10t it's easy to over tighten the wheels and bind up the drive train. Spur gear should be a 87 tooth and if bashing around with it I'd start with a 18 tooth pinion with a 20t motor.

Ok thanks. I don't notice any binding in the drivetrain, the pinion is a 25T that I had laying around and that could be the issue. I was figuring it might be, but wanted to be sure before ordering another. It's basically just bashing or getting used to a real rc before I drop the money into the one he wants. Thanks for all the replies

Running a buggy like that through thicker grass and for long run times might also cause your over heating issues. Gear mesh between pinion and spur should also be checked. Too tight and you will strain the motor.

Google is your friend and I found a PDF on the Associated web site that might be worth a read.

https://www.teamassociated.com/pdf/c...ear_ratios.pdf