Voltage issues please help!
 

I have a 220 1987 Kawasaki bayou and In some wiring I'm getting 10 volts. This wiring goes through a couple different things like the voltage regulator which it's still getting a good amount of voltage coming out of there and a black box which is the igniter. I still haven't tested the igniter yet but at the ignition coil we're getting 2.5-3.0 volts. Please help I have no clue what could be draining the voltage. Also how many volts needs to go to the spark plug in order to create a spark? Thanks for reading and any possible ideas would be awesome to hear!