Here is the bike after removing the wheels and the handlebars. I’m ready to remove the front forks, steering stem acorn nut, top plate, steering stem pre-load nut, chrome dust cover and the steering stem with the bottom triple clamp attached to it.
Tools
I use a cut-down, 36 mm socket to remove the fork tube top nuts. These are often tightened to 70 Ft-Lbs and the face of the nuts is not very tall, so you need as much contact surface between the socket and the nut as you can get. On most sockets, the edge is tapered so this is what I removed using an abrasive wheel. I checked the socket on a glass plate to ensure the face was flat and square.
I use the hook spanner included in the bike tool kit to remove the slotted steering bearing pre-load nut.
Video
Here is a short video summarizing how I do this work.
VIDEO: 1983 BMW R80ST Charity Build: Remove Front Suspension
Remove Front Forks
The front forks are held in place with the top fork tube bolt and a pinch bolt on the lower triple clamp. There is a bracket under the top fork bolt that secures the top of the headlight bracket.
Before I remove the bolts, I drain the fork oil. There is an Allen bolt in the top of the fork tube nut that I remove. Then I remove the drain bolt to drain the fork oil into a pan.
I remove the top fork tube bolt with a 36 mm socket that has the end cut down so it is square. The top fork bolt flats are not very tall and they can be installed at 70 Ft-Lbs of torque so you need full contact on the faces of the nut with the socket so you don’t round of the nut. These fork top nuts are loose so they came out easily. There is a bracket under the nuts that secures the top of the headlight bracket. Then I remove the fork spring.
I remove the triple clamp Allen pinch bolts. I use a large blade screw driver and a plastic mallet and drive the screwdriver blade into the slot on the side of the triple clamp until the forks slide free. I keep my hand on the fork tube as I hammer the screwdriver into the slot so the forks down fall out and slam into the floor.
I labeled the fork tubes so when I rebuild the forks I will install the fork tube into the same fork slider.
I pulled out the fork springs and measured them. They are about 19-11/16 inches or 50 mm long.
Remove Steering Stem
The top fork plate and steering stem are attached to the steering head with a large acorn nut underneath which is a steering head bearing pre-load nut on top of a chrome dust cover. I remove the top acorn nut with a 36 mm socket.
The steering head bearing slotted pre-load nut is on top of the chrome dust cover. I use the hook spanner included in the bike tool kit to remove the slotted pre-load nut and then the chrome dust cover.
The steering head top bearing pre-load nut top side is flat and wide, but the bottom side of the nut is tapered to a narrower face that pushes on the top steering head tapered roller bearing to adjust the pre-load of the steering head bearings.
Then I use a plastic mallet to drive the steering stem out of the frame. The top inner race will slide up the steering stem releasing the steering stem from the steering head. I will remove the inner bearing races inside the steering head when I replace the steering stem bearings.
Here is the bike with the front suspension removed.