Re: what did you do to your motor bike today?
If that engine ran at all with the white wire grounded to the frame (black wire), you have a bad ground. My kill switch runs the white wire to a water bottle screw in the frame, and it cuts out 100% as soon as I touch the kill switch.
If you are talking about a grubee/happytime, you will need a handlebar switch for the light system. Mine runs, even at idle, with the lights on, but is hard or impossible to start with the lights on. I had to run a pretty narrow gap on the plug, to compensate for the lights. I am using a 6-12v automotive/maglite type bulb on the front "bullet" light, and a 12v LED tractor trailer side marker light for the rear. The LED helps keep from blowing bulbs.
There is a 12v "generator" for happytimes, that goes in the magneto case and runs its own wires for your lights. If you run that to a battery first, you will need a regulator (11.5 or up to 13.5 volts), to keep from cooking your battery.
If you want to keep it simple, find a mud flap from a diesel truck, one that fell off at the docks or something, cut a wheel out of it about 8" across, with a center hole to fit your hub (front or rear wherever you want). ziptie it to the spokes through some small holes , leaving a 2" track at the edge. Then use a 12v tire dynamo, clamped to the bike where it will run against that rubber donut.Then, you don't wear out the dyno, don't wear out the tire, and it shouldn't be affected by mud or rain.
Got it fixed... sorta. I had also taken my white wire powered light off. For some reason, this was keeping the spark from firing. I "fixed it" by connecting the white wire to the black (ground) wire. It then ran... for a time. I then had to disconnect the white wire again as it wouldn't run with the wire shorted out like that, but runs now. ...although it feels like it's lost power and it won't idle unless I've got the throttle opened at least, oh, 1/8th or more. Adjusting the idle screw doesn't help at all.
Help?