Mountain Bike Headset
Nobody likes a squeeky bike. Certainly not me. So after the bike company* couldn’t (wouldn’t) help me fix the creak in my headset, I set to work myself.
To me, the cause was clear: too much play in the system. If something creaks, it means it can move. I was right, the difference between the outer diameter of the bearings and the inner diameter of the seats in the frame was 0,2mm (!). Same with the steerer tube and head tube reducer.
Brass foil.
Both bearing seats in the frame are 50.2mm in diameter.
The outside diameter of the bearings is 50.0 exactly, so I glued a 0.075mm strip brass foil to it. This reduced the tolerance to 0.05mm.
Installed the lower bearing with the brass foil. Together with assembly paste, no more play
The head tube reducer also had way too much tolerance and could even wiggle around the steerer tube. The steerer tube is 28.6 mm (1 1/8 inch), which is standard, and the reducer was 28.8mm. Again, 0.2 mm.
After measuring, I created a solid in Shapr3D and later converted it to a 2D drawing for machining. Tolerances are a lot tighter now.
Reducer fits like a glove, both in the bearing and around the steerer tube.
NO MORE CREAK!
* I blacked out the brand name, to avoid any negative attention for this particular brand.