THey are just back from where the motors plug into the board. The cover of the RX18 is pretty easy to remove, and you can see them for yourself. It might aid in the cooling as well. Everyone with a Heng Long should consider the 3:1 gears. I mean this in all sincerity. The 3:1 gears keep the motors out of the stall range, where they draw the most amps, and then heat, and kill the FETs. I run my FOV diecast sherman using an RX18. This tank is heavy, and this is the tank I made this discovery on. When it had regular gears in it I fried one board. I replaced this board and was running the tank without the turret on I noticed the new one was running extremely hot. So hot I could feel the heat escaping from the turret hole. I put 3:1 gears in it, and the heating problems went away. Runs all day long with no heat buildup.

The only thing is you do lose some top end, and if possible you should use the motors that turn 18,000 rpm to make up for this if you are running the lighter faster tanks. Heng long used to have white cap and black cap motors, and I think they ran at different RPMs. 11,500 and 18,000.

Radio shack or the "Source" also catalogs suitable motors at these different RPM ratings as well. I have never been one for the high end motors. I let the 3:1 gearbox handle the torque. I have some old 1/24 scale cox slot car motors. I was going to experiment with those one day. I haven't yet as I am pretty sure they draw incredible amps, and frying a Hegn long board would be a certainty.