We have a '98 Softail custom that has developed a starting "problem"..Days, weeks, months go by & it starts ok & runs great..then for no know reason it will not start..grinds, but no spark. You leave it sit over night & it starts right up. Voltage to coils is fine, switched out cam sensor once when it was acting up & still wouldn't start. When it won't start we have replaced spark plugs, giggled wires & done just about everything we could think of but it still won't start. Next day or in 4 or 5 hours it starts right up. Anyone who could help would be much appreciated. Is there some computer in it that needs to reset itself?????????

 

Check all the wiring in the ignition system including the handlebar switch and look for crimped or exposed wires causing a short. Check the ignition switch itself, they have been known to wear out.

 

Just a thought .... I've seen this happen with an ignition coil. The coil heats up and then has a thermal breakdown. After it cools a while, it will be OK again. You might try taking some OHM readings when the coil is cold, put it in an oven at about 150-200 degrees and bake it for a while. Take the OHM readings again. This trick works sometimes. If the readings are off target signifigantly then maybe a new coil would be in order. It could be that while riding there is enough air to keep the coil within limits. After you park, heat from the engine may be enough to push it over the edge.