Sunday, December 15, 2013

'67 BSA Big, Bold, Powerful!

 When I was young and first got interested in bikes one of the first projects was a '67 BSA Lightning. This was a bike my father purchased from a neighbor for $50. I remember carrying boxes of bike parts home. We had no idea what the bike was supposed to look like until we saw a pic in a workshop manual.

 A lot of time was spent on this motor. Partially for my benefit to learn about engines and part because as I now know, if you are working on a Brit bike for the first time there are a few things you need to wrap your head around. Lucas electrical, how to set the timing and British Standard to name a few.
 The cylinders were honed and oversized pistons and rings were installed along with all the other usual things done during a rebuild. We had such a hard time getting this engine running and spent a lot of time second guessing ourselves and double checking our work. I remember taking turns with my brother pushing the bike in gear trying to get the bike to fire up. We would try kick starting the bike with nothing to show for our efforts except a sore leg. Oh sure once in a while it would burp at us for a few seconds or even allow a short 50 foot blast up the drive, but that was about it.
 Other projects came and went. Seasons came and went. The BSA sat waiting in the corner of a few different garages. It sat eleven years before one day my dad asked me if I wanted it. I had eleven years of gear head experience behind me and felt I was ready to take on this project that had kicked my ass as a wrenching wannabe.
 When I was a kid I understood ignition systems from a text book viewpoint. Now I understood them from experience. It didn't take long to get the bike running but something else was going on with this beast. I could never get it to run smooth.
 After a few days of messing around with it after work I was starting to get goofy about this project. Was it gonna kick my ass again?
 I kicked the bike over and she came to life but ran crappy. Then it would run good, then bad again. I had a furnace fan blowing cool air over the motor so it wouldn't over heat. I pretended the air from the fan was the wind blowing my hair back. I leaned to the left then the right as if I were racing through an S curve. No bikes in my mirrors, I must be in the lead. A gentle sweeper to the right and she's purring like a kitten. Get on the brakes and scrub off some speed for the next left hander. Push hard on the left bar... Hey, what just happened? When I leaned left it ran like crap. When I leaned right it cleared up. After a few more laps on my pretend race track I was certain the bike was flooding one cylinder when I leaned left. Even if I only leaned a very small amount.
 Back on Earth after a little investigating I discovered a casting flaw in one of the Amal carbs. There was a small hole right about at the top of the fuel level in the bowl. Fuel was spilling from the bowl directly into the venturi. I used some JB Weld epoxy to plug the hole and an hour later I was riding the bike around the parking lot. It ran dang near perfect. Whodathunkit.
 I rode 200 miles on the bike before a bearing in the trans siezed up. Well, I rode 196 miles. I pushed it the last 4 miles home.
 That was over 20 years ago. I haven't had it running since then. I have worked on it a bit but only enough to figure out what was wrong and what was needed to fix it. I think I even bought a bunch of parts for it. I'll have to go out in the shed and take a peek. Every year I say that this is the year I will put it back together. Every year passes without that happening. This year I was getting serious about the bike and decided to borrow an inspection camera from Al. Unfortunately the camera showed what I feared. All that kicking and push starting attempts without decent oil circulation created some scoring in the cylinders.

 Also, this area that appears to be shiny concerns me. I think its actually rust pitting from sitting so long. Its not above the scored areas so it must have come after the 200 mile fling and wasn't the reason for the scoring. My bad for not fogging the cylinder better. I guess it really doesn't matter because it has to come apart either way.
 I'll get a better look at it when I tear it down this winter. Next year is the year I ride again...

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