Thank you Magnetoman, and I really do appreciate the expertise you and the others have offered. As you say, it is very hard to diagnose electrical problems this way, because often all the factors are not obviously stated in postings. In this case, the ATD problems I was having two weeks ago prompted me to go to manual advance. This happened so quickly since the manual change was made to another magneto. Way back in the thread you will find that the original magneto I used and had trouble with was exchanged for a second one, and that was the one that seemed promising. Now I have the original one back, refurbished, re magnetized, tested and converted to manual. To make things even more confusing, I did not mention that the second mag is one that I have had at the rebuilders for a couple of months, made from a disassembled but complete mag that was given to me. To help me out, the rebuilder was kind enough to expedite the restoration and sent it to me at no charge while troubleshooting the original. I will have the second one back eventually, since while it seemed OK, I sent it back in last week for a final look and check because I have been having so many problems. I could use that one to diagnose problems when I get it back, but I would have to get a new ATD or fix my old one to use it. I had hoped to spare everyone what seemed unimportant details, but probably just confused matters by the omission. I also want to state the high regard I have for the rebuilder, for whom I have great respect and confidence, and who has bent over backwards to try to get me through this. Any discussion there has no place in a public forum, and I am uncomfortable even saying this much. I was hoping someone could tell me whether "I" was doing something obviously stupid, and as it turns out I was, in several respects. So much so that I wish this was not so public a venue. Too much information with only entertainment value. Still, I can't tell you how much I have learned in the past month about ignition systems.
Back to the matter at hand, I have used the same wiring, plugs, and pickups on the bench as on the bike. The cam is a v twin 50 degree cam, and I have used my magneto timing tool and a degree wheel to determine correct points opening on both cylinders. This is easy now that the bum ATD is gone. The plug wires are Packard 440, and the caps are nice new sparkies. You may to be on to the spark escaping somewhere else, but I can't find it. The mag does not care about external timing if the plugs are clamped to a fin, so if no sparks happen then, I can only look to bad ground, leaky wires, or something about bolting the flange to the engine that changes things. Despite my complaining abut my knees, with the plugs out and clamped to the fins I have been able to swing the kickstart fast enough to test the spark. Finally, since this is the magneto I had the original problem with, there certainly could be some internal intermittent fault that has been missed. If this is the case, I do not want to be at its mercy 50 miles out, even if it suddenly starts to work if I happen to get something right during troubleshooting. The points and coil system should get me running and answer some of the questions I have, including the tuning of the brand new Amal concentrics. I can then address what is going on with the magneto at some length, including doing some of the things you talk about in the excellent Magnetoman series you have linked here on this forum and the DIY section on the bright spark website. There are some good tests and diagnostics to be done with close inspection and the basic tools I have.
I hope to be at the SL reunion Rally in early July , so getting the bike running now makes further magneto troubleshooting a luxury.
Mothers Day just passed, and as my dear departed used to tell me, " your mouth runs like a whippoorwill's butt"
Ron
