QuestionWhen I run this bike for any length of time it will not restart if the engine is hot. i replaced the ignition coil but dont have any idea what else to do. can you help? thanks
AnswerJered... which version Nighthawk? 650 or 700?
Do you mean that it turns over and doesn't start, doesn't turn over or something else?
Do you have spark when it doesn't start? Do you have fuel?
You could have fading pulse generator coils, heat sensitive ignition module, wires/wire connectors with corroded connections. There is more than one coil on this bike. You have to isolate if you have spark on all 4 cylinders or just two when this happens. Check spark plug caps for 5k ohm resistance values. All four should be close to the same value. How old are the spark plugs?
On the fuel side, there are vacuum operated petcock diaphragms and air cut diaphragms that can fail, causing fuel supply issues and/or air leaks into the intake tract. Gas caps/tanks with venting issues can create a fuel vapor lock causing fuel flow problems, as well.
Bill Silver
