BMW motorcycle telescopic fork bushings
This article is included here because it covers the US forks of the /2 series.
This page is about the BMW Airhead motorcycle models; R50/US, R60/US, R69US, R50/5, R60/5, and R75/5. The BMW telescopic forks were introduced in 1968 on the /2 models and were designated by the suffix “US.” When the /5 models came out in 1970, they had the same forks. One of the several problems with them was that of stiction caused by the bushings. These bushings are located at the bottom and just up inside of the fork tubes. They are held in by a snap ring. The old fixed bushings were replaced with “floating bushings” in 1972. This change solved the stiction problem from that source. Other sources, even larger ones, still existed.
Original bushing
Three-piece floating bushing
All three pieces
The change is recommended for those forks that may still have the older, one-piece bushing. The two outer threaded pieces trap the aluminum centerpiece but still allow it to “move or float” around. You can see it in the middle photograph. The piston rod will not “stick” while moving up and down.
If your forks are not in nearly perfect alignment, then this change won’t help much. This is a small hole in the dam. I suggest that you plug up the larger ones first.
Go to the excellent article by Randy Glass on this issue.
Read the factory service bulletin on this issue.
Updated 15 July 2022