no spark but coil is good

Making leaps and bounds in my quest to ride the 81 seca 750rh. Following the forum suggestions i replaced that fuse box and wow what a difference. All my lights work and my start is way easier. Problem is that i have nothing on the 1 and 4 cylinder. I have pulled the coil and put in one from a buddys working bike and nothin.. i have to admit i have the heaviest 2 cylinder on the block! ANy sugestions??

 

Try your buddy's TCI.

 

Then check your pickup coils and the associated wiring between the TCI, pickups and coils. A bad ground will mess up the works as well.

 

I have this same problem except Im getting no spark on 2 and 3, with both coils testing good. How should I go about troubleshooting this?

 

If you swap the input plugs to the coils and the problem follows the plug, you know that it is something further up-stream. The TCI or a pickup coil. Otherwise, it is the coil for sure.