Motorcycle Repair: electrical problems, suzuki gs450, jap bikes

Question
i have a 1980 suzuki gs450 and i have weak electrical power to one of the coils. the other coil sparks just fine. i do get power but not enough for the spark plug to spark. i checked to coil and it is good. but every once in a while it gets good spark. what can it be? do those bikes have points? if i take the black/yellow wire from the good coil and connect it to the coil with no spark then both of the coils spark great

Answer
Bryan,

  I am not an expert on the older Jap bikes.  The last one of these I had in the shop was running on just one cylinder( like yours) and the dealer told me that the only way to trouble shoot was to substitute "known good parts" for the suspect parts.  
  What I did was go to a local salvage yard and got a CDI box and a new pick-up assembly and changed them all...the bike ran fine and I was out less than 100 bucks...if you dont have a salvage yard within reach , email me back and I will get you the number for the one that I use.  He can UPS the needed parts to you and you can change them out

  Good luck, Hopefully I have helped a little

D