Okay, so I’ve been wrenching on bikes for a while, and I’ve always had a soft spot for the old BMWs. The /5 series, especially, just has that classic look. So, when I saw a 1972 R75/5 pop up for sale, I had to jump on it. It wasn’t in terrible shape, but it definitely needed some love.
Getting Started
First thing I did was just give it a good look-over. Checked the fluids, tires, and the overall condition of, well, everything. I noticed a few things right away:
- Oil leak: Seemed to be coming from the pushrod tube seals. Pretty common on these old airheads.
- Carburetors: Definitely needed a good cleaning. Probably gummed up from sitting.
- Brakes: Front brake was pretty spongy. Needed to bleed the lines, at least. Might need a rebuild.
- Electrical: Some of the wiring looked a little… sketchy. Old and brittle.
The Teardown
I started with the carbs. Took them completely apart, soaked all the jets and little bits in carb cleaner, and made sure all the passages were clear. Used some compressed air to blow everything out. Gave them a good scrub.
Next up, the oil leak. I ordered new pushrod tube seals,and pulled off the cylinder heads. This also gave me a chance to check the valves and make sure everything looked good in there. Decided to check the valve clearances while I was at it.
Putting It Back Together
I installed new seals, and carefully put the heads back on. I torqued everything down to the correct specs, of course. Then reinstalled the carburetors after I made sure that they were properly clean.
I moved onto the brakes. I bled the front brake lines, and thankfully, that firmed things up nicely. I’m going to keep an eye on it, though. Might need to rebuild the master cylinder eventually.
The Electrical Gremlins
I spent some time tracing wires and replacing any that looked cracked or damaged. Found a few loose connections, too. It is a bit of a puzzle, to be honest. I just took my time and checked all the connections to be sure.
First Start!
Finally, the moment of truth. I put some fresh gas in the tank, turned the petcock on, and gave it a kick. It sputtered a bit at first, but then it roared to life! That classic boxer engine sound… music to my * it for a short ride around the block, and it felt great. Still a few little things to tweak, but it’s running and riding!
It’s a project, for sure, but it’s rewarding to bring one of these old bikes back to life. And the R75/5? What a beauty!
