(I hope I don't embarrass Kevin by posting this, but I wanted to share this with the group... Also, this is kind of a long story but hopefully others might be able to chime in ideas about the troubles I was having.)
This past weekend my wife and I both volunteered to work on the Route Safety crew for the Susan G. Komen Breast Cancer 3-Day. For those unfamiliar with it, a group of participants (in the case of Michigan this year it was 1,800) walk 60 miles over the course of 3 days to raise money and awareness for breast cancer (as well as other cancers). I lost my grandmother 3 years ago to the disease and my wife's aunt is a survivor. We love working the route safety team as they require the use of motorcycles (as well as pedal bikes) to patrol the route looking for walkers that need help as well as manning intersections to make sure the walkers cross safely. My CB750 and Cynthia's CB550 are usually the oldest bikes there, but we have another guy who rides his 1981 DOHC CB750K. In a sea of Harley riders, we have to stick together!
Anyway, the Tuesday before the event I rode to dinner with some friends. On the way home my 750 started acting funny- it developed a misfire. This was unsettling, as the 3-Day was coming up and I would have to rely on my bike to do my job. Plus, I did not have much time to look into the problem. I first looked over the fuel system, as at the time this only occurred on the highway so I first suspected it was a fuel starvation issue. However, after a late night of looking in the carb bowls, blowing out the carb jets and fuel lines, removing the petcock, etc. everything looked fine on the fuel end. This pointed to the ignition system as the culprit, and I did not have any more time to investigate the issue. I figured since the plugs were almost 3 years old, maybe one was starting to fail so I replaced them. No change. Since the problem began to occur at slower cruising speeds as well and only when the bike was warmed up I began to suspect either the ignition coils or Dyna-S module I installed about 4 years ago. Luckily I still had the old set of breaker points and cam, so I tossed them in my saddlebags in case I should need them. I also checked over all of the electrical connections and they were clean and tight. The problem was not caused by bumps, but happened when the bike was running at constant throttle and on smooth pavement.
Into the second day of the event, the problem became gradually worse. This was really wearing on me, as I didn't know if my bike was eventually going to die on me and not make it through the weekend. Luckily, the overnight camp was less than a mile away from Kevin's house, so I gave him a call and told him what was going on. He had all the tools I needed and to my surprise he also had an extra set of ignition coils so I could swap them out too if I thought they were part of the problem. After day 2 wrapped up, I headed over to Kevin's house and we got to work. After an hour we swapped the coils, reinstalled the old breaker plate and re-timed the ignition. The bike was running good, so I was ready to take on day 3, which ended up taking us into the city of Ann Arbor- if the bike conked out there, I'd be in deep trouble...
Fortunately, we nailed the problem as the bike ran like a Swiss watch all day! While I was working on the points, Kevin was checking the coils with an ohmmeter. The ignition wires for the 1-4 coil were only intermittently making a connection. We likely would have had to snip off a length of wire to get a good connection, but the wires had already been cut before and this would have rendered them too short. I may eventually reinstall the Dyna, but for now I think I'll stick with points. Maybe I'll go for a HondaMan ignition instead...
I can't thank Kevin enough for his help and generosity as he helped me avert disaster. It was a tremendous relief that we corrected the problem and I would be able to complete my commitment and be able to get home. Thanks again, Kevin!!
