After looking at lots of tired and bent wheels for sale, I finally found this one on eBay. According to the seller it has a date stamp of 12/78, so it probably came from a ’79 bike. It looks like it will clean up nicely.
There are some interesting differences between this wheel and the one it’s replacing. In the earlier wheel, there are raised vents with plastic grills to scoop in air. In this wheel, the raised portions of the hub are still there, but the vents are not cut out.
On the inside of the hub, they’ve added the 10 bars that you can see running between the brake lining and the edge of the hub. Perhaps these are meant to move air around? They’re also lined up with the radial spokes, so more likely they’re there to stiffen the hub around the brake lining.
Those bars aren’t present in the ’77 wheel. If you look closely, you can see one of the black plastic vents below the left edge spline cup. Click on the picture for full resolution.
The ’77 wheel on the left is aluminum alloy and has a smaller, 35mm seal on the right side, and a 36mm seal on the left. The right bearing is pushed in from the left side. The ’78 wheel is also aluminum, except for the hub center which contains a steel sleeve. The bearings are pressed in from both sides on this wheel and both seals are 40mm. Both of these wheels use the same bearings, which is good, because I’d already ordered a couple. These bearings are also used for the swing arm and front wheel.
As soon as the new wheel arrives I’ll get to start over on splines and bearings. Yeah!