Clod Pinion & Electric Problems

[Super Clodbuster Junkie 26]

Hello, 

My Super Clod is having some problems. I ordered two 5000mah 7.2 volt NiMH batteries, but I only got to use them once because my truck started sounding bad. I took the truck apart and found that the stock 13-tooth pinion gear had "shark-toothed". Then I did not drive the truck for a couple months, and then got two of these 15-tooth pinion gears from CPE (Crawford Performance Engineering) and this suspension lift kit also from CPE. When I installed the two items, the truck turned, but would not do any thing else. I soldered a wire back onto one of the motors, and the truck started running, but drove extremely slow, and the truck sounded bad. It sounded like a loud zipper with sand in it. In other words, it sounded really gritty. What should I do?

[Saito2 6686]

Unless you have some form of adjustable motor mount or have modified the gearboxes to accept different size pinions, go back to the 13 tooth pinions immediately. The stock Clod gearbox only accepts 13 tooth pinions. The original pinions "shark-toothed" because they were aluminum and wear out. Use steel 13 tooth replacements from a source like Robinson Racing. Simply installing 15 tooth pinions in the stock Clod gearboxes will really jam things up. Honestly, at this point, I'd check the gearbox over to make sure any damage hasn't already been done. I'm surprised CPE's website mentions nothing about the need for gearbox modification in the product description. It is somewhat (though not intentional) misleading.

[speedy_w_beans 4272]

Maybe I'm missing something, but I don't remember the gear boxes having extra holes to mount the motors differently for different pinions...  If you installed 15T pinions in place of 13T pinions and didn't change the motor mounting then the pinion and spur gear are likely bound up/interfering with each other. That would lead to overloading the motors -- slow movement and noises.  I'd source 13T steel pinion gears instead such as Robinson Racing #0130 Steel Alloy Motor Pinion Gear, 1/8" / 32 pitch / 13 teeth or even CPE-PIN13: Replacement 13T/32P Steel Pinion

The CPE 13T pinion is likely a Robinson pinion resold with their packaging.

Edit:  Saito's on it!

[Super Clodbuster Junkie 26]

Thank you for the help. I probably will check out the gearboxes today. I hope there has not been any damage done.