well, i don't think you can even measure spark voltage with 95% of meters out there, and even if that was right, you need at least 10,000 volts to make a plug fire. read through the tech documents on thissite, they are stickied in this section, and availiable from the homepage. you can also use a sparkplug box to set the gap on the flywheel. i'm leaning twards a bad coil, because that's about the voltage you would see going into the coil, but it could possibly be the stator or flywheel, too.