The length of the shaft - which is the threaded portion - is 1-1/4 inches long for the Bauer Products T-Handle Lock for Truck Caps - Clockwise - Matte Black # BA27VR. view full answer...
The Yakima OnRamp Bike Rack for 2 Electric Bikes - 2" Hitches - Frame Mount, part # Y36FR, has a different weight limit when on a RV or motorhome. On your Class C motorhome the per bike weight limit is 40 lbs, so it is not really ebike capable on a motorhome. A better option would be the Hollywood Racks Sport Rider SE, part # HLY84FR. It is rated for use with RV/motorhomes, without a weight reduction - that weight limit is 80 lbs.
I have included a product description link and a video... view full answer...