YTM225 CDI help

[smvorndran]

I rebuilt my YTM225 the other day, but I can't get it running because I believe the CDI is shot. Could somebody please check the voltage at their coil wire, and let me know what you get? I'll describe my process, and maybe someone will have an idea. The ignition coil only has one orange wire, which supplies the voltage to the coil from the CDI. It grounds thru the mounting bolts to the frame. The YTM is a negative ground, so the orange wire would need to have positive juice going to it. My process of testing it is this. 1. I hook the negative wire of my voltmeter to the negative post of the battery. 2. I connect the orange wire from the bike to the positive wire on my voltmeter. 3. I crank the engine with the electric starter. It registers at NEGATIVE 6-8 volts. 4. I pull start it, and it registers at NEGATIVE 12 volts. I think that proves the CDI is bad, but was wondering if someone could test theirs, and let me know their results. It took me about 10 minutes to remove the tank and do the tests. Any help would be appreciated. I'm about to take it off and send it to a guy to test mine on his running trike, but I thought I'd ask here first before I went thru the trouble of removing it & shipping it.


Thanks,
smvorndran

[bigreddaddy]

Your meter is showing negative because you must have your probes backwards or your not testing it right. Put the ground probe on the frame somewhere and the positive probe on the Coil hot wire.

[smvorndran]

That's what I did. Negative probe to ground, positive probe to the orange wire. Negative voltage spitting out. My meter is good because I hook it up to my battery, and it shows positive 12 volts. My neighbor stood there watching me, and he was scratching his head as well, and he's a maintenance tech.

smvorndran

[bigreddaddy]

Do the same tests but with the probes switched. It should show the same reading without the neg.

[smvorndran]

Yeah, it's positive 6-8 volts with the probes backwards. Still, negative voltage going into the coil. I need to check my SX, see what it has.

smvorndran

[rocketman123]

I cot a coil from dennis kirk that was like 39 bucks brand new and it has a hotter voltage too. its a Rick's HotShot coil. If your coil is bad, this wouldnt be too bad of a fix.