Motorcycle Repair: tach/miss

Question
I have a 1979 low Rider and the tach at times (more often than not) is bouncing all over the place. Checked wire at coil that goes to tach and it appeared ok. The bike when it gets warm will also seem to have a miss when driving down the road and tach bouncing all over. When bike is warm and in neutral, while tach is bouncing, neutral light flashes also. Is there any relationship with these two problems? Is it coil or ignition or something else electrical?

Answer
You probably have 3 different problems. The tac bouncing all over is common with those old tacs. It picks up an impulse from the coil, when the coil fires. There is no repair for the tac, you have to replace it. Is the miss just every once in a while, like a cough? On the neutral light, the neutral switch is probably going bad
Mike