After installing the flywheel, I’m ready to install the clutch. You can see how I install the flywheel here.
Installing the clutch is a straight forward procedure.
I use a special tool that I bought from Euro MotoElectrics that centers the clutch plate on the center of the flywheel. It aligns the the clutch plate so it will be centered with the transmission input shaft. I only have to rotate the transmission input shaft to align the splines on the transmission input shaft so they line up with the clutch plate splines.
I am installing new clutch parts as shown in the list below.
|21 21 1 338 680 (Bolt)
21 21 1 242 377 (Washer)
|Clutch Bolts & Washers||6|
|21 21 1 338 508||DIAPHRAGM SPRING (from 09/80)||1|
|21 21 2 302 200||PLATE (from 09/80)-Pressure Plate||1|
|21 21 1 451 512||CLUTCH PLATE (from 09/80)||1|
|21 21 1 457 280||HOUSING COVER (from 09/80)||1|
I made a short video showing highlights of this procedure.
VIDEO: 1983 BMW R100RS Install New Clutch
Clutch Parts and Markings
Here are the new clutch parts I am installing.
Clockwise from the top left,
- Diaphragm Spring
- Clutch Plate (aka, Clutch Disk)
- Pressure Plate
- Housing Cover, (aka, Front Cover)
The clutch parts are attached to the face of the flywheel with six M7 bolts and washers. I am installing new bolts and washers.
I took some pictures of the clutch parts and the part# markings on them.
Clutch Housing Cover
Clutch Pressure Plate
Clutch Diaphragm Spring
The flywheel, pressure plate and clutch housing cover have white paint balance marks. These indicate the heavy area of each part. To balance the engine, each part is mounted 120 degrees from the others so the clutch is balanced. It is important for a smooth running engine to evenly distribute the balance marks when assembling the clutch parts on the flywheel.
Preparing Clutch Parts
Even though these are brand new parts, the metal contact surfaces need to be cleaned to remove oil and debris. I use brake cleaner and blue shop towels and clean the contact surface of the pressure plate and the clutch housing cover. I do not clean the clutch plate’s friction surfaces.
I apply a very thin smear of Moly 60 grease on the contact surfaces of the diaphragm spring and the pressure plate. The six ridges on back of the pressure plate contact the front of the diaphragm spring. The rear edge of the diaphragm spring contacts the face of the flywheel so each gets some Moly 60.
Install Clutch Parts
I turn the clutch housing cover over so the contact surface faces up. There are three locating pins, each 120 degrees from the others.
I put the clutch plate on the contact surface of the clutch housing cover. The side of the clutch plate without the sleeve faces me. The transmission input shaft fits into the sleeve, but goes in from the other side of the clutch plate.
I attach the pressure plate on the three pins of the clutch housing cover. Each of the three straps on the pressure plate has three holes. The center hole in the three straps fit over the pins on the clutch housing cover. I make sure that the white paint balance mark on the clutch housing cover and the balance mark on the pressure plate are not on top of each other.
I flip the assembly over so the outside of the clutch housing cover faces me to verify I have the clutch plate installed correctly. The sleeve the transmission input shaft slides into should face me.
Then I put a light coat of Moly 60 on the peak of the six ridges on the back of the pressure plate. The peak of the ridge rubs against the front of the diaphragm spring and the Moly 60 will reduce wear on the ridge.
I orient the white balance mark on the flywheel so it is at the bottom of the flywheel.
I put the diaphragm spring on the face of the flywheel with the bow in the spring facing me so the perimeter of the spring is against the face of the flywheel.
The three pins on the clutch housing cover fit into three holes in the face of the flywheel. I orient the clutch pack so the paint mark on the clutch housing cover is near the top (next to my thumb in the picture below), and the paint mark on the pressure plate is at about the 4:00 position. Since the flywheel paint mark is at the bottom, this positions all three paint marks approximately 120 degrees apart so they are NOT on top of each other.
I attach the clutch pack to the face of the flywheel with two new clutch bolts and washers. I thread the bolts into the holes so the clutch plate is loose between the clutch housing cover and the pressure plate.
I insert the clutch centering tool into the center of the clutch plate so the pin on the tool goes into the small hole in the center of the flywheel. This centers the clutch plate on the flywheel so it will align with the transmission input shaft when I install the transmission. Then I install the other bolts and finger tighten them all.
Once more, I verify the location of the paint marks. I verify the flywheel mark is at the bottom and the clutch housing cover paint mark is at the top.
I rotate the flywheel counter-clockwise to position the pressure plate paint mark to the top so I can see it through the top of the starter motor opening. It’s hard to see since it’s on the edge of the pressure plate. All three marks are 120 degrees from each other and none of them are on top of each other, so all the parts are installed correctly and the engine will run as smoothly as possible.
I use a socket wrench to tighten the six bolts until they are snug. To prevent the flywheel from turning while I torque the bolts, I put a large flat blade screw driver between two teeth of the flywheel with the screw driver shaft against the left side of the oil pump cut out. Then I torque the bolts to 15 Ft-Lbs in a cross-wise pattern.
I remove the clutch centering tool. The clutch is installed.
2022-03-23 Correct typos.