Originally Posted by Randy M
thanks so much but I did check the same connections as in your photos and they looked as new. Also I had the ign sw apart last summer (no use since then other than the aborted test ride) and the terminals all looked fine.

However, as you mentioned previously, operating the ignition switch seems to cause things to change so could be worth another look.

Originally Posted by Randy M
I DO have 13.75 v where the Yellow& White (also Blue and White) wires come back to the seat area from the kill switch after going from batt to ZD to ign sw to kill switch.

If, as you said previously, white/yellow is powering the Boyer as it had been white/blue (there are white/blue WU and blue/white UW wires on a T160) then white/blue shouldn't have voltage so needs investigating where it's getting its power from.

Originally Posted by Randy M
Thanks to you after about 180 hours spent I now have spark during cranking (and kicking, and under compression) by following your and Stuart's advice. I installed a 7.5 amp fuse en route.   However weirdly after I disconnected the batt to solder in after mocking up, when i reconn the batt the dash lights lit up. (Current going in reverse?) Not knowing what to do I turned the ign ON and then OFF and that seemed to reset it and its normal again.

It seems unlikely that power going to the dash lights would have come from the C4 terminal without the starter button being pressed, and once again, operating the ignition switch appeared to cure an apparent problem.

Originally Posted by Randy M
Any thoughts on issues A and C?

I thought 'A' was what we had been discussing.

Originally Posted by quinten
C4 should only be hot when the start button activates the starter relay .
the fuse needs to protect against overloading the kill-switch ( in a couple of unexpected scenarios )
( there is a possibility for current to go both ways when the start button is pressed )

If there's no power in the electrical system then the relay wouldn't operate but if power was lost during the relay operation then I expect that could happen.
A diode (oh no, back to diodes again) connected to WY I think would prevent that.