Moving on to the rear hub and clutch requires that I get the scooter up on the lift, and get the motor up off the ground. I locked the front wheel in the wheel-vise, and got the motor airborne. This allowed me to get the rear hub off the rear axle without too much trouble.
I can't tell you how much easier it is to work on these scooters with a table lift. You can do all this work with the scooter on the floor if you have to, but it is just much less of a strain up on the lift!
The next thin that has to be done is removal of the spare tire. It hangs down and blocks access to both the rear hub and the clutch.
When I pulled the side cowl off, I immediately noticed three issues with the spare. First, the rear bolt that holds the spare onto the frame had fallen off. The front bolt was finger tight, so it too, was about to fall off. Second, the air stem on the tire was mounted in the wrong direction. It needs to run across the rim. In this configuration, it is likely to hit something if it is mounted, and break off. Not very good for a spare. And finally, I noticed that the bolt that holds on the spare tire cover is not mounted to the frame, but just the tire. That means that this tire was held on by just one finger tight nut. Much more riding, and it could have fallen off!
I will have my friend re-mount the tube and tire, and I'll make sure to put on some lock washers behind the nuts when I install it again later.
With the spare out of the way, I could then move on to the rear hub. I pulled the chrome cover off the rear nut. The rear hub is held onto the rear axle by a single nut. The nut is supposed to be torqued onto the axle, and as a fail-safe mechanism, there is a cotter pin which locks the nut in place. The top of the nut is slotted, and the axle has several small holes drilled in it. The cotter pin slides through the slots in the nut, and through the holes in the axle.
When I removed the chrome cover, I immediately noticed that the nut was not locked into the cotter pin. Upon closer inspection, the nut was completely loose. It looks like a crucial spacer behind the nut was omitted when it was previously assembled. This meant that the nut was too close to the hub, and ended up being located behind the cotter pin. The cotter pin was essentially doing nothing to lock the nut. At least it served a function of stopping the wheel from falling entirely off. I'm sure with much more riding, the cotter pin would have sheared in this configuration, allowing the nut to back off the axle... yowch!