Motorcycle Repair: 1963 Honda c110 50cc Primary coil, honda c110, secondary coils

Question
How do you check the primary and secondary coils in the ignition to see if they are still good? thanks! Ron.

Answer
Ron,

Check out the wiring diagram at http://oldmanhonda.com/MC/WiringDiagrams/MCwiring.php#class

If the inside of the flywheel/rotor is nice and clean where the magnets are, you should be able to see volts coming out of the stator leads, testing it with a small 6/12v test light or a meter, when you spin the motor over.

To test them individually, you would have to dismantle them from the backing plate, isolate the ends of the coils from ground and test for resistance and for grounding to the coil mount. They are just coils of copper wire, but they must be insulated from each other and not grounded to the mount internally. When installed, one end does go to ground and the other one out to the rectifier and/or the ignition secondary coil, depending upon what coil it is. Most common "no spark" problems are dirty/worn points, points not adjusted properly and a bad condenser.

Bill Silver