I been having issues with my 78 GL1000 with poor running engine in the midrange. Tonight I took the left belt cover off and I marked the pulley with all the firing points and the max advance points and I made a pointer for reference.
What I found was somewhat confusing. Overall the ignition is jumping around quite a bit. From the movie it looks like it varies about 4-6 crank degrees on the front coil pack between the two cylinders but the rear pack is right on but there the full advance mark jumps. It seems to me that it jumps more than the back lash I can notice in the belt.
Please look at this and let me know twhat you are thinking.
Ulf