Vintage BMW Motorcycle Owners

I'm having to go through the entire brake system for the front brake. When I got the bike, front brake was spongy. Didn't think I'd have to do this much, but in the long run, it's worth it.

Took the hose off between the master and the hard-line. Hose was old, brittle and the inside was very small. Took the caliper off, and pushed the piston out with some air. lots of dirt/debris inside. The dust boot looked horrible. Once I cleaned up all the debris/buildup, was much happier. No pitting on the piston or in the cylinder. Have that all cleaned up now, waiting on the caliper rebuild kit.

Today, decided to look at the master. Removed the rubber boot, and there was fluid in it. Bad sign. Took the master off the bike, and it was very rusty, with rust on the frame underneath it (All surface rust). Got the master apart, and at least there is no pitting inside the master. Used a green scotch brite pad, and took all the rust off of the frame as well as the outside of the master. A little paint, and the bare metal is now protected. Painted the master, and ordered the rebuild kit. Also - when I pulled the light switch, there was a lot of teflon tape on the threads - and the crush washer was missing. Ordered a new switch as well as the correct crush washer.

So - when I get done with all of this - the front brake should be perfect. Fingers crossed.

Great news! It is good to read about your progress. St.

OK - update:

I ended up replacing everything because of leaks or lack of ability to bleed. So - 2nd used caliper (repainted). Replaced seals and bleed screw, and used a new piston. New brembo carbon ceramic pads. New hard line. New flexible line. Bought a brand new master - had to plug one side, but it's fine. Final bit was a new brake cable.

Bled the system last night. Put the tank back on today. Rode the bike around the neighborhood today - idle is set stupidly high (like 3000 rpm). Idle adjustment and rode around some more. It's already running better.

Rear tire was mushy. Tried to add air and couldn't. finally got the valve out, and it was a mess - looked like it had corroded in half. Replaced it and put air in the tire. Much better.

Just added some seafoam to the tank, and will continue to ride to see if carbs improve. I'm hopeful it will clean itself out, vs me having to pull and rebuild them. I want to ride a bit now.

Pics are on instagram: https://www.instagram.com/bigpurpledummy/

You might want to do a valve adjustment on it, that will help idle. Also, Check points.

How old are the tires? It may be a good idea if they are very old to replace them. St.

Valve adjustment, new plugs are in the plan. Front tire is brand new. I need to look for the date stamp on the rear.

One more quirk. When the bike is running, every so often when the left turn signal is flashing it honks the left horn. Any thoughts? It doesn't do it when the motor isn't running but the electrical system is on.

I don't see any connection between the horn and the turn signals. The horn is a button the left bar and just completes a power path to the horn, which is grounded at the horn. The turn signals are on the right bar. I wonder if there is some non-standard wiring on the bike. Might have to trace the wires and see where things are mixed up.

Realized where it's coming from now. It's a little buzzer on the frame mounted back by the battery. It's really loud when the turns signals are on, and the ignition key is on, but the handlebar switch is set to off.

I wonder if one of my turn signal grounds is failing?

OK, that's different! I have that same "beeper" on my /7. It's a subtle note that the turn signals are on. Some people don't like the noise...I prefer to keep the warning there.

OK - so it's not a problem, it's just a 70's thing so I don't ride around with the signal on.

OK - good to know. I'll leave it alone.

The signal light beeper on the /7 is actually a fairly elegant setup.
If it is working correctly it will only beep if you are in gear and the clutch is engaged. This eliminates the annoyance of the beeping while you are waiting for a light or stopped in traffic.
Car drivers are usually blind to the existence of a motorcycle, but a forgotten left turn signal blinking will only encourage them to turn left in front of you.
Ride safe,
Brett