HPI 39T High Speed Idler Gear... Increase of up to 20mph!?

[Finnster]

An idler gear is a gear that does not offer gear reduction. Its like a spacer between two transfer gears. 20T or 40T, no change in gear ratio. Same concept as a chain between sprokets on a bike. Longer or shorter chain, no diff.

However, this idler allows you to use a different set of transfer gears, which have a lower gear ratio. That is what drops the final drive ratio and allows for more top end. Same effect as if you put a larger pinion on the motor.


This was released bc the gearing was already a bit funny in the flux. Std pinion was 20T. Not a huge room up for bigger pinions, and spur can't get much smaller than the 44T on there now. Just adds flexibility, plus its a stronger material than the other idler, so a more bulletproof. Nothing magical otherwise.