Idle Gear? More Like Hard-Working Gear [Tech Center]

Since I upgraded to brushless power, my truck keeps eating up the middle gear in the transmission. How can I make it last?

 

The idler gear is the hardest-working gear in your transmission. It meshes with both the top-shaft gear and the differential gear, so it’s subjected to a lot of stress. To prevent idler gear blowouts, make sure you’re using your car’s slipper clutch properly, if equipped with one.  e slipper clutch should be set just tight enough not to slip under full-power acceleration—any tighter is “too tight.” If the drivetrain is loaded more heavily than a full-power acceleration, a properly set slipper clutch will do its job and slip rather than transfer the shock to the internal gears (where the idler gear will take the brunt of the abuse). For maximum protection against idler gear failure, upgrade to a metal gear if available or to metal gears throughout. Many brushless-powered RTRs include metal-gear transmissions for exactly that reason.

 

A metal idler gear will outlast a plastic one.   is hardened steel gear from Robinson Racing is for the Associated SC10.

 

Traxxas specs metal gears in all its 2WD brushless models to prevent gear problems.

A properly set slipper clutch will go a long way toward protecting the transmission’s gears.