Picked up a timing light, how do I use it?

[Joesxs650bobjob]

Note the position at full advance in the pic. There's no official mark for full advance, but people use the left side of the drain hole in the cover. You can advance the timing if you want, but you shouldn't advance it so that it goes past the drain hole at full advance. It's an engine killer. I have mine timed the same place yours is now, to allow me to use 87 gas.

For changing the timing, on your pickup is the top hole a slot or just a hole? If it's a hole you have to turn it into a slot. They came both ways. The thing that looks like a rivet holding it on on some of them is a screw with no slot. Just cut a slot in it and it'll back right out.

So I’m trying to change the timing right not how do you do it just move the mag pickup!!?

 

[5twins]

Yes, just move the pick-up slightly. As mentioned, you may need to slot the mounting holes a little if they're not already. Which way you move it will depend on what you're trying to do - advance or retard the timing. I would assume you want to retard the timing slightly. To do that, you need to move the pick-up away from the direction of rotation so the magnet on the rotor triggers it later. The motor spins in a counterclockwise direction so that means you would have to move the pick-up to the left slightly.

 

[pamcopete]

The dual output coil produces a positive voltage on one of the spark plug wires and a negative voltage on the other. By convention, the timing light works best on the negative voltage spark plug wire, but there is no easy way to tell which wire that is, so if you are seeing erratic operation of the timing light, or it doesn't work at all, try clamping it to the other spark plug wire.

 

[xjwmx]

If you have to slot it, just slot the top hole and let it pivot on the bottom hole. That's how the pre-slotted ones are. They're the same except for the slot. To retard push the pickup to the left and to advance push it to the right, although I can't picture a need to advance it. How much slot you need is the same as how far you want to move the timing mark. Grind it with something sharp like diamond burr so it doesn't heat so much.