I have a 2000 Vstar 650 here. I have weak spark on front cylinder only. I have gone through the manual and tested every component in the no spark troubleshooting guide. I have replaced the ECU with OEM new and the relay box where the diodes live. The spark coils are new and have battery voltage at the red/black wire. The orange wire to ECU tests good, no excessive resistance and not shorted to ground. One strange symptom is that the front cylinder has spark but will not sustain running. The pipe heats up so I know the fuel is burning but it feels as if it's ignighting on the exhaust stroke. I have pulled the flywheel and checked the key way. I really am out of ideas now.