The wheels are the next project to work on. The plan is to take them apart, replace the chrome spokes and nipples with stainless steel spokes, inspect, lube and set the preload on the wheel bearings. I decided to have Woody’s Wheel Works inspect the bearings and lace up the new spokes. Here is a link to the write-up on this work.
When I removed the bearing cover on the rear wheel, the left side bearing outer race had loosened and spun in the aluminum hub. There are various options to fix this including:
1. Using locktite on the outside of the outer race to secure it to the aluminum hub.
2. Staking the outer race to try and keep it captive in the aluminum hub.
3. Adding a shim around the outside of the outer race so it is captive in the aluminum hub
4. Buy a new hub.
I posted my problem to the airhead forum on the Micapeak site looking for input on these options and any other ideas. The consensus is:
- Option 1 can work, but also can fail
- Option 2 always fails,
- Option 3 works well,
- Option 4 is expensive and since new hubs are no longer available from BMW, is not a viable option.
I also got a response from two folks in Australia with a variation on shimming the outer race. Their fix uses a thin steel sleeve called Speedi-Sleeve, provided by SKF bearing company. It is designed for use on shafts that have been scored by the shaft seal. Adding a Speedi-Sleeve stops the oil leaking past the seal and retains use of the original oil seal. The sleeve that fits the R75/5 wheel bearing is #99157. It’s 0.28 mm or 0.011 inch thick so it adds 0.56 mm or 0.022 inch of material to the aluminum hole holding the bearing. It is installed on the outer race with a special tool. Then the bearing stack is assembled using the axle with a spacer and is put into the heated aluminum hub. This is the standard procedure for installing the bearing stack into the aluminum hub. When the hub cools, it contracts around the Speedi-Sleeve and outer race shell and should hold the shell captive to the hub. This is the solution I choose and had Woody’s install the Speedi-Sleeve.
Here are some pictures from the write-up.