So like the title says. My 1985 bug zapper... I mean my '85 K100 makes a sporadic ticking / bug zapper noise when the engine is cold. The noise comes from the engine's left side (valve cover/fuel and ignition side). But it's too hard to pinpoint exactly where. I use the word sporadic, cause it IS NOT the scheduled ticking noise of the fuel injection. You could also say it's an erratic or irregular noise. I also need to say that it happens 9 out of 10 starts while the engine is cold. Outside temp doesn't seem to play a factor. When the tick/zap noise occurs, it sounds like the RPM changes for a split second (like you turned the key off/on REALLY quick). Since the RPM changes, I'd assume it's a fuel or ignition thing. I can't think of what it could be, since it stops after a few miles of driving due to the engine warming. I'm having a hard time isolating this faulty part that would function better when warmed up.
I need to give you a brief history. This bike belonged to my Grandpa (before him it was my Dad's). My Dad renewed the registration, inspection, and filled the tank. To prepare for the season. That was 8 YEARS AGO and at his age, he didn't feel comfortable getting back onto it. He pass nearly a year ago. My Dad signed it over to me and I spent Aug and Sept ordering lots of parts (battery, lights, tires, fuel pump and damper, etc.), cleaning, painting, servicing, converting into a naked, and "renewing" her.
I think it wouldn't hurt to get the injectors cleaned out, since the pump was clogged and bad. Although I don't think that is the answer. Fuel injector flow shouldn't change with warming up. I can't imagine it's an internal mechanical engine issue.
Does anyone have any ideas or suggestions??? Please help!
