buy a volt meter, continuity tester and start checking each circut one at a time. wiring issues are not to hard to figure out but you will have to invest some time
Ok so, A friend of mine has an 87. We discovered the cdi was bad so we put a 94 cdi wired right to the stator I believe for a few wires. Stator, magneto and rectifier are all from the 94. His headlight is dim, blinkers don't work and brake light doesn't work. Anyone know what else we need to do to correct this? Bike runs great.