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Old 08-09-2009, 09:27 AM
  #627  
bluesxman
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Originally Posted by Swift and Sleek
I HAVE ATTACHED PICTURES OF THE POSSIBLE AREAS THAT MAY CAUSE THE PROBLEM.

MAY I ASK IS THE PROBLEM RIGHT HERE?
Swift, that's not impossible, but if you shimmed it like the manual, I doubt it. For me, the factory build made the meshes very loose. First, I think you need to isolate the problem. I'd do this:

Slide motor pinion away from the spur. Do the wheels spin freely?

If not, disconnect the drive shaft. Which end does not spin freely?

Open up that end. Any damage? Are gear teeth stripped/melted? Are all the bearings spinning freely? Shimmed too tight? Clean it up and shim it looser if necessary. You can loosen/tighten the mesh between the bevel gear (BG1) and the diff gear (BG2) with shims. You can change the 10mm shims (BA12) on the diff or the shims on the propeller joins (BA20, BA21).

Personally, I did 4 BA12 shims on the short side of the diff and 2 on the long side. I also did two BA17 shims on the propeller joints. This all tightens up the mesh between the bevel gears and the diff. While its on the tight side, my drive train still spins nice and smoothly with the motor disconnected.

Now, if your drive train spins freely with the motor disconnected then there's several things it could be:

1) The mesh between your pinion and spur gear was too tight. You want a little bit of play in that mesh.
2) Motor needs cleaning. Spray it out and lube it.
3) Motor needs rebuild/replacement. How have your motor temps been? Is it possible you cooked it? As for fixing and maintaining brushed motors, I am not the guy to ask. My fix is to run brushless.
4) Could your ESC or radio be causing the motor to brake when you let off the throttle? Perhaps the ESC has a really aggressive drag brake setting? Perhaps your throttle trim is way off on your radio? You could check those settings or try new electronics on the car if you have them available.

If you have other motors/escs/radios or friends who are willing to help you out, you can always try swapping these out to see if one of them is the culprit.

Anyway, I hope that gives you some ideas. Step 1 is to isolate the problem.

Last edited by bluesxman; 08-09-2009 at 09:40 AM.
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