Motorcycle Repair: spark to rear plugs, resistance values, salvage yards

Question
I have a 1986 honda shadow.  I have no spark to the rear cylinder..  neither plug.   the front caps both get spark.   each coil has a black wire in and one has a yellow and the other a blue.  the blue wire will spark front or back if I move it.  Im stumped.  I have cotinuity throughout.  Thanks Brian

Answer
Brian, you didn't mention if this was a 700 or 1100cc version, but they are probably both similar in this regard.
Moving the wires back and forth, as you have, revealed that the coils are not the problem.

There should be two pulser coils adjacent to the flywheel that generate timing signals to the spark modules and out to the coils. I suspect that one has failed. You can isolate them from the harness and check resistance values with an ohm meter. I think that the yellow set will show open or a different value than the blue set. Check the wire connectors coming off the right side of the engine for those wires. This is a $150 part. Hopefully one of the control modules are not to blame, as they are $400 each!
Start shopping the salvage yards...

Bill Silver