1963 Honda C102 no spark


New Member
My friend has a c100 and convinced me to buy a c102 that was for sale. I'm mostly familiar with working on 49cc scooters from the 80s until now so no experience with these 60s hondas.

I am not getting spark and can't figure out exactly what the issue is. It has a new battery, new points, new condenser, new spark plug. I checked the ignition coil and it tested right. compression tested around 93. There's no neutral bulb but i got a reading around 3V to the neutral bulb socket when put into neutral.

The ignition had been changed to a toggle switch that has red on one end and all the rest on the other. When it's on i can get the starter solenoid to click from the button, but i haven't messed with the starter motor and nothing happens to it.

It's possible i just dont have the points gapped correctly as I couldn't find anything specific enough to follow to do this in a particular way. I have seen a single spark (or atleast enough current to spark) once or twice but it was very weak and this was before a battery was put on it.

I'm wondering if the selenium rectifier may be bad but don't know how to test it or whether that would impact spark. Are there other electrical components to check? Any information on various forums has been around the c100 which appears to be quite different electrically from the c102 that I got.
Try this. With a continuity tester or test light, make sure that the points ground out when they close and are an open circuit when they are open. Then remove the spark plug and lay it on the head (wire still attached). Get a good 6 volt battery or 6 volt power supply and hook the positive to the hot side of the coil. Ground the neg wire to the engine case. The cold side of the coil should go to the points. Kick the engine over and see if there's a spark at the spark plug gap. If you get no spark, try replacing the condenser.