[lurkingknight]

bearings aren't that much better than bushings.. in fact I prefer bushings.

what was your method of shimming? did you start from the pinion to bevel mating or did you just start throwing shims into one gear and start from that?

The reason I ask that if you did not start from the pinion to bevel mate, you could have shimmed the bevel too high and you're causing the pinion to bind on the bevel with too much resistance.

The other possibility is that it's shimmed too tight. there should be just a bit of side to side movement in the gears, about 1-2 sheets of paper width movement in all the gears with the 2 halves of the gearbox screwed together.

To shim it from the pinion to bevel, take the bottom half of the gearbox and put your bevel in, take your motor grip and screw it into the half of the gearbox and install the motor into the grip with the baseplate. The pinion should meet the bevel and mesh nicely, but not tightly with the bevel but not be too far towards the center. If the pinion is resting on the bevel then the bevel has too many shims under it. It's too high. Adjust it until it has a bit of play.

From there, take the grip and motor off, and shim the bevel from the top with the other half of the gearbox so that it has 1-2 sheets of paper of side to side play. From there work up the gear train.

It also helps to superglue your bushings or bearings into the gearbox shell so they don't move. if they slide around they can throw your shimming attempts off... and if there's slop they can actually rotate in the shell (bushings moreso than bearings) and end up enlarging the bushing holes in the gearbox further causing misalignment in the gears.


furthermore... I agree the g&p 120 is a shit motor.