Motorcycle Repair: How to test magneto output, yamaha dt250, volt system

Question
Hey I have a 1974 Yamaha Dt250. I am wanting to check the output of my
magneto with a multimeter I have. I was wondering if you could tell me what the
output should be in AC. I know that I would probably fluctuate as the rmp varies,
I was just wondering if you could tell me maybe and average. Thanks!

Answer
Matt,
usually the larger coil is for lighting and
charging, they can output between
15 and 30 volts AC on a six volt system.
The other coil will have a lower resistance
reading and can output up to
a hundred volts to charge the ignition coil.
The readings can vary alot, sometimes
replacement is the only alternative
to find a shorted coil.