It is easier to remove the four drive shaft coupling bolts that connect the drive shaft to the transmission output flange with the rear wheel on the bike. That way I can use the wheel to immobilize the drive shaft when I remove the bolts.
You will see red duct tape on parts of the bike in some of the photos. I use this “red flag” when I remove oil or gear lube, I need to torque a fastener, or I haven’t finished work on something and I have to stop. It helps me prevent inadvertent disasters. All I have to do is remember to reapply these red flags after I clean, repaint and powder coat the parts. Maybe I’ll try the Uncle Billy “string-on-the-finger” trick 🙂 (see, “It’s a Wonderful Life”)
Remove Drive Shaft Coupling Bolts
I remove the special bolt on the right rear of the transmission that secures the speedometer cable and the battery (-) ground cable. The bolt has a longitudinal hole that lets the the swing arm breath as the rear end moves up and down. I run a wire through the hole to ensure it is not blocked.
I use a small screw drive to pry the rubber boot off the ridge on the transmission, slide it up the speedometer cable and pull the speedometer cable with it’s bushing out of the speedometer drive gear hole in the transmission.
To prevent anything from falling into the transmission speedometer drive gear hole, I fill the bushing with a piece of blue shop towel and insert the bushing back into the hole in the transmission.
I remove the two steel bands that secure the rubber bellows that fits between the swing arm and transmission.
They aren’t in good shape and come apart when I remove them. The rear strap fits next to a small metal tab welded to the front of the drive shaft housing on the swing arm that acts as a retaining clip for the bellows.
I slide the front end of the bellows off the transmission and bend it back to get access to the four drive shaft coupling bolts.
If rear brake is still installed, I put the transmission in second gear, sit on the seat, put my foot on the rear brake pedal and then loosen the bolts. But in this case, the rear brake has been removed and the bike is on the portable motorcycle lift. So, I use a different technique to immobilize the rear drive when I remove the drive shaft coupling bolts; a large, long screw driver through the web of the cast wheel with the transmission in second gear. The screw driver will wedge against the shock preventing the transmission coupling from turning as I loosen the four bolts.
I use a 12 side box end 10 mm wrench and remove the four drive shaft transmission flange bolts. It takes a goodly grunt to break them free.
A common practice is to put blue loctite on the threads of these bolts when installing them. If your bolt’s seem hard to turn, you can try using a small flame on your propane torch directly on the head of the bolts to melt the Loctite. Be careful as you can burn the rubber bellows if you aren’t careful.
Be careful as you unscrew the bolts to not drop them as they will be hard to retrieve from inside the swing arm.
After I remove a bolt, I remove the screwdriver in the wheel, rotate the wheel to position another bolt to the outside of the coupling where I can get the box wrench on it and then reinsert the screw driver. I continue until I remove all four bolts.
There are two styles of these bolts. The old style, part# 26 11 1 230 414, is longer, 15 mm, and used a split lock washer, part# 07 11 9 930 840. The washers tend to break so BMW revised the coupling bolts with a new style, shorter 13 mm bolt, part# 26 11 1 242 297, and eliminated the split lock washer. If your bike has the old style bolts, throw them and the split lock washers out and replace them with the new style.
Remove Rear Wheel
Now that I have removed the four drive shaft flange bolts, I remove the rear wheel. I remove the rear axle nut on the left side and then the pinch bolt on the right side. The axle nut should have a large flat washer, but someone replaced it with a split locking washer and the pinch bolt hardware is incorrect too, so I’ll replace all of it with the correct hardware.
There is a hole in the left side of the axle so I can insert the rod in the bike tool kit or a screw driver to remove the axle. But, it won’t slide easily since the brake plate is binding on the axle. I remove the brake torque arm lower mounting bolt from the plate and the axle slides out easily under the muffler.
There is a serrated washer behind this bolt that is not stock. And the arm is mounted on the front side of the brake plate; it should be on the back side..
The rear brake torque arm plate is oriented as shown below and has a casting number stamped in the side with the reinforcing ribs which faces to the outside of the wheel.
The rear tire does not want to go past the splines in the rear drive, so I deflate the tire and it comes out. It is the correct size, 4.00 x 18, but I guess it has a fat profile.
I check the splines on the inside of the rear wheel for excessive wear and they appear to be in very good condition.
The rear disk mounts to the cast wheel with five bolts. There is also a circular strip of metal with bent tabs to secure the bolts and prevent them from backing out.
Remove Brake Torque Arm
Now, I remove the brake torque arm from the bracket on the bottom of the swing arm.
The front end of the torque arm has a bend and a bushing on the side of the torque arm that faces inward while the rear end of the torque arm is straight and also has a bushing that faces inward.
Here is how the bike looks now.
Remove Rear Drive & Shocks
The rear drive has a stud that the bottom of the right shock mounts to. I remove that shock first, but leave the left shock mounted to the swing arm until I remove the rear drive. This keeps the swing arm from dropping down against the frame with the weight of the rear drive.
The inside of the rear drive has splines that engage splines in the rear wheel to turn the wheel.
I check them for wear and find the profile is rectangular, not rounded, and there are no chips or cracks on the splines, so they are in very good condition.
I remove the right shock starting at the top. That allows me to rotate the shock out of the top bracket of the rear sub-frame so I can slide the bottom of the shock off the stud in the rear drive.
These are not the original shocks (thank goodness). There is a metal bushing inside the rubber bushing of the shock.
Now I remove the four 12-sided bolts that secure the rear drive to the swing arm. Due to interference with the swing arm, I use a universal joint adapter on the socket.
I use a plastic hammer to free the rear drive from the swing arm. As soon as I get it loose, I understand why I had to use the hammer; the gasket that is supposed to be used isn’t there and instead someone used sealant. That’s not the correct approach.
Now I remove the left shock. The lower shock bolt won’t clear the left exhaust pipe, so I have to remove the left muffler to get the bolt out.
If you install the left lower shock mount bolt with the bolt head on the inside of the swing arm, you can pull it out and not have to remove the muffler when you want to remove the shock or the swing arm.
The bottom shock bolt and nut are different. The bolt is shorter, has finer threads, and the nut is thinner. This helps when removing the wheel by providing more clearance.
Remove The Swing Arm
The swing arm is secured with two pivot bolts and nuts to the frame. These are behind a black plastic cover. I remove the covers using a small blade screw driver in the notch in the cover to pop them it out.
The lock nut requires a cut down 27 mm socket with a thinner body so it will fit inside the frame. The nut should be quite tight so I use a breaker bar to remove it.
I use an Allan key to remove the two pivot pins. I hold onto the swing arm as I remove the last pivot pin so it doesn’t fall onto the floor.
This what the bike looks like now.
2019-11-27 Edits and typos.