[nixiebunny]

Originally Posted by Michael Yeh

Another question about the 3CIM4U: is the output shaft supposed to be longer than the kitbot's? We recycled the one from the kitbot but since there's now 1/8" of gearbox in between it doesn't fully extend into the outer bearing.

We used the long shaft that came with the upgrade kit. It doesn't protrude fully into the bearing, but it is in deep enough to work. No troubles through the Hub City regional.

Beware that the inner spacing is also different due to the gearbox plate - we had to add a VexPro 1/2 hex plastic spacer between inner plate and wheel to keep the wheel hub bolts from scraping the inner side plate. We also had to file the AM14U bearing holes as the spacing between them was different from the 3CIM gearbox.