Working with Rodney @Old_Houseboater on a new project. He posted a little about it a couple months back but here is an update teaser.
Increase speed of stock 2016+ GEM to 40+ MPH while maintaining reasonable range.
Reduce gearbox noise - factory gearboxes are really (really) loud.
Below are some pictures of our test mule.
This is a 2016 GEM, What @Old_Houseboater has built is a new gearbox (10:35) and half-shafts that will replace the factory gearbox. The only modification needed is to drill four new holes to bolt the gearbox down and swap out the half-shafts. The new gearbox mounting holes are slightly wider than factory. You use the factory mounting brackets on the new gearbox. This simple swap will take a factory GEM from 25MPH to almost 42MPH with stock wheels and tires.
These gears are quiet It is hard to tell in the video below but high speed is normal gear noise as expected from a classic GEM and regen is almost silent.
We still have some work to do on the half-shafts to get the length perfect but we are not far off.
I will report back exact speeds once I can get a decent day for testing.
@Old_Houseboater - anything to add?
Video of a short test run: