engine quitehile riding WOT, electrical issue

Discussion in 'Electrical' started by TomONaBike, Jun 10, 2012.

  1. TomONaBike

    TomONaBike New Member


    I was riding a 66cc frame mounted engine on my way back after an 8 mile ride. I was three miles in when the engine went from running very smoothly to cutting out completely, hasnt been back since. I have checked all the mechanical issues, gas runs out of the float pan drain screw, filter clear, choke working, clutch is good, and sure enough there is no spark.

    So i switched spark plugs, no luck, disconnected the kill switch, checked for loose wire connections, all appear to be working. I had problems with spring boot and connected the CDI to the copper core wire and then to another wire that attached directly to the top of the spark plug. I have since gotten an ohm reader to test for connectivity and got the spring boot working. The magneto looked good and the magnet for sure, so I thought it must be the CDI. Then I found a long thread on magnetos going bad and took mine apart. It definitely does not have the recommended readings. There was no activity from blue to black. It appears to have a oily finish on the top surface of the metal where the black washer connected that prevented electrical connection, and the solder joint also no longer connected electrically.

    So i cleaned off the top piece of metal, resoldered the three little wires coming off the coil and now it seems to be behaving much better, but not quite right.

    Blue to black = 220 ohm
    Blue to white = 220 ohm
    Black to white = open

    In my attempt to check the soundness of the CDI connections, (by splitting open the plastic box) I destroyed it. But now I think my magneto needed to be replaced, even though I was able to identify and redo a faulty solder joint.

    New CDI for sure, Im going to get a new magneto, but I would like some thoughts on what I could do to get this one back on line.