Ok so building a superjet i bought off of craigslist that was all in a box... went trough everything and rebuilt motor ect... was told all electrical parts worked when tore apart ( Like I believed that

)
SO I get this thing all together hit the start button and wham It fires! runs for 20 seconds and then dies! I hit it again and again and think what happened. I pull the plugs, hit it again and no spark. Hum I ( stupid kill switch) so I unplug the starter wires and the kill switch wires and jump the starter, no spark still.
I had a spare Cdi in the tool box, i throw it on and hit the starter and it fires, runs 20 seconds and then dies, now no spark... ( and still No kill switch hooked up)
I did a test on the pulsar coil and its showing 2 volts AC, charging coil is at 30 AC and battery charging is also where it is supposed to be. The pulsar coil seems to be low on volts by tow or so....
I have tried two cdis two different coils, im kind of baffled at this point.
anyone got any idea on where i am going wrong?