Hondaman, is there a simple, not too expensive way to test coils simulating riding conditions. In other words: what do you use to generate let's say 15-170 Hz?
After our Honda coil tester "suitcase" failed in 1972 (it had a vibrator tube to generate the simulated points activity) I built a solid-state multivibrator to drive the tester with. I left that one in the suitcase when I left my shop, but built a similar unit for testing and burn-in of the Transistor Ignitions I make now. It's a simple flip-flop circuit of a couple of transistors that invert the pulse for the 2nd coil so it runs just like in the bikes. If you'd like the schematic for it, I'll see if I can find it: it's in one of my (many) bikestuff notebooks, but I recently got a scanner so I can digitize some of this stuff!
I don't remember the RPM range of this one, but it is somewhere around [simulated] 5500 RPM that I run the test burn-in time, about 2-8 hours per unit (depending on if I remember to turn it off at bedtime?).
The interesting thing I noticed about these coils/debris sites is: the upper one in the picture is driven by the negative-pulse side of the circuit, and the tiny flakes are coming off the electrode: the lower one's flakes are coming off the ground arm. So, they do wear in opposite directions, like the old Suzuki notes suggest.
