QuestionI have a 78 honda CB550 that I am having trouble starting. I have gotten it to start before by adjusting the position of the regulator away from the frame of the bike. On other attempts to start the bike i have seen a spark arc from the area of the regulator, i wasn't exactly sure where it came from. Is it possible that the regulator is grounding out on the frame or more likely the regulator is just bad?
AnswerMatt, the regulator doesn't have any direct bearing on the bikes ability to start, other than if the battery voltage is too low due to regulator failure. The E terminal on the regulator should be a green wire and goes to chassis ground. The rest of the regulator case is supposed to be insulated from grounding. This is a mechanical regulator and the points can get pitted, corroded or overheated and fail.
Go here for helpful specific troubleshooting, plus as a source for replacement parts that are probably better than the originals. http://www.electrosport.com/electrosport_fault_finding.html
With the battery fully charged, the bike should start and run with no problems, unless you are having blown fuse problems. The ignition system is dependent on the charging system to keep the voltage up for the coils. Be sure that the ignition points are clean, gapped to .014" at the maximum opening, then set to open at the 1-4 and 2-3 F mark alignments with the engine case pointer.
Make sure your plugs are fresh, the plug caps all have about 5k ohms resistance, measured when taken off the end of the wire ends (then unscrew).
If your fuel system is clean and set to specs, it should be a good runner again, if the compression is all about the same on all cylinders.
Bill Silver
