K bike clutches
« on: May 15, 2011, 12:52:35 PM »
This thread includes three sections on K bike clutches:
1 - How they work
2 - How to adjust them
3 - How to replace the clutch plate and/or O-ring
1 - How A K Bike Clutch Works
The following is a general description of how K75, K100 and K1100 clutches work. The basic design is the same although some of the individual parts vary between the models.
The clutch assembly is attached to the engine output shaft via the clutch housing. (Yellow) In addition, the clutch housing provides some rotational inertia to the clutch assembly.
The clutch has two pressure plates. (Blue) The rear pressure plate is fixed to the clutch housing and does not move. The front pressure plate “floats” on three flat arced springs around it’s perimeter. (Red)
The diaphragm spring (Purple) pushes the front pressure against the clutch plate (Green) and the rear pressure plate to engage the clutch.
When you pull in the clutch lever, the clutch lever arm on the back of the transmission pushes the clutch push rod (which goes through the transmission input shaft) into diaphragm spring and compresses it. The front pressure plate can then “float” away from clutch plate and the clutch is disengaged.
2 - How To Adjust A K Bike Clutch
The following is a page from a BMW service manual that describes how to adjust the clutch:
This page is also attached to this thread as a PDF file at the bottom of this post if you want to print it out separately.
3 - Replacing The Clutch Plate or Clutch Nut O-ring
My procedure for doing this is attached as a PDF file at the bottom of this