Weak spark to one plug

I have an '82 KZ750M (twin) that I have been working on the past couple of years and I think my work is finally coming to a close. The issue I am having right now is week spark to one cylinder. I have replaced the plugs, wires, and caps but still nothing. I switched the wires to the opposite cylinders and it did not fix the problem. The wire/plug that seems to be working fires about once every 10 turns or so while trying to start it. That spark also seems to warm the pipe up but the other stays cool.

I just want to be able to ride the thing once before I end up selling it out of anger!

Tried another brand of sparkplug? How are you checking the spark? I prefer using testers, as using a plug can stress the ignition system.

Ignition Spark Testers
www.lislecorp.com/divisions/products/?pr...ivision=1&category=8
www.lislecorp.com/divisions/products/?pr...ivision=1&category=8

Im using a NGK b6es so brand probably isnt the issue. As for a tester, I have one that is similar to the one in this link:

www.powersportsplace.com/parts/wmr-w8053...f7hbkCFalAMgodTFkAqw

The flashing of the tester is inconsistent and doesnt flash at a consistent brightness on the weak plug.

You may want to consider checking Voltage to the coil. That was a big part of my problem... I'm certainly no expert, but it's a place to start. I just went through my entire electrical system cleaning all connections with deoxit dn5. Made a huge difference in terms of lighting, and power to the coils. Good luck!