This is one of those things I try to do to every BMW motorcycle I rebuild.
This area is cracked on nearly every frame I tear down. It is the rear foot brake area which also is the muffler / silencer hanger, and where the passenger foot pegs attach. This frame is a 1978 BMW R100s. If you are considering rear sets on your bike that attach to this section, then I HIGHLY RECOMMEND doing this procedure.
cracked tab near rear foot brake pivot hole on BMW airhead framecracked tab near rear foot brake pivot hole
cracked tab near rear foot brake pivot hole on BMW airhead frame
New piece of metal to weld onto the old cracked section to reinforce the area making it MUCH stronger and no longer prone to cracking.
Welded metal onto the rear foot brake section of a BMW R100S
Finished powder coated frame with the welded metal. This area is out of sight to most people unless they take the rear tire off.
I don’t know what went on with my powder coat shop (Hy Tech) but finally, months after I dropped it off, they finished it.
We tried finding a few different powder coatings but nothing matched the Porsche silver we are trying to match to. We did find something else and it is really close to the color we are trying to match.
It is a High Temperature liquid coat that gets sprayed on similar to spraying on powder except it isn’t electronically charged like powder is. It can be applied to other surfaces then metal.
It is a catalyzed Polyurethane that is baked on in an oven. Though not as hot as powder baking… and not as low as baking car paint.
It is a custom silver color that is made for Stop Tech brake calipers. It is resistant to Brake fluid (which eats away any sort of paint). So if this is resistant to brake fluid, you know it is durable stuff.
It doesn’t go on as thick as powder.
And i believe there is a clear coat over top of it…
Like Santa came and left me some presents to unwrap:
I finally broke down and got a race puller from Cycle Works. Here is a step by step on how to pull the steering bearing races from the neck of the frame.
Photo courtesy of Cycle Works
Note the way the split washer sits on the bolt.
The washer needs to go behind the race. You may need to tap it into the neck.
I had to use a few long sockets and extenders to reach the 10mm head of the bolt through the other side of the neck.
When you tighten the nut onto the bolt, it expands the split washer to fit tightly behind the race. This will help pull the race out.
Insert the slice of tube(collar) and attach the nut with the large washer as shown. Make sure the piece of tubing sits centered on the frame aligned so the race can slide out into the tube.
27mm socket to tighten the nut. Breaker bar with socket extension through the neck attached to the 10mm nut on the bolt.
After some torque and cranking, you can feel the race start to pull out into the collar. Eventually, everything will pop out as shown. Save an old race. Next time you use the tool, you can keep an old race in the collar to prevent the collar from warping, and to help guide the next race out.