06-02-14, 01:08 PM
The first thing to do, as always with dodgy electrics on bikes, is to go through the entire system checking the harness for damage and cleaning all the connectors... from the battery (and don't neglect the negative connector) via the fuse box, the big bundle of connectors in the box under the tank all the way to the ignitor box in the tail of the bike and the contacts to the coils. Clean off corrosion, tighten the female halves of connectors and spray with contact cleaner afterwards to inhibit further corrosion.
Check the wires to, and contacts of, the immobiliser bypass plugs (all black wires) on the harness at the back near the ignitor, I had a wire chafe through there and it killed the sparks very effectively.
There are other possibilities, but thorough inspection and maintenance will identify most faults of this type and it can be done without a multimeter.