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Running on rear cylinder only

I have the same problem with my sporty but mine is the back cylinder, has spark and getting fuel but nothing out of that one cylinder and when I give it gas it dies without the choke so maybe its the same scenario? any suggestion?

Did you read this post?

Problem resolved!:D

A case of several issues, both unlikely, masking each other.

Problem # 1: I removed the coil and had it tested. While the technician said that the resistance tested within parameters, it was very marginal. In short, it wasn’t officially bad, but it was very close to it. Given that the testing is done under very different conditions than typical riding conditions, and the erratic spark quality I observed, I chose to replace it.

Re-assemble the bike to the point where I could start it. It starts! Both cylinders fire, reasonabley regularly.

BUT:

It smokes like a (EDITED). And fuel is still standing off outside the carb! Pig Rich. Hmm.

I find the old CV-40 carb, and slap it on to see how it runs. The bike fires right up, runs much better (considering the carb isn't even tuned to this build), no smoke. Must be a problem with the Mikuni, eh?

I pull the bowl off the mikuni, check for dirt, check the float, pull the jets—just looking for something unusual. Nothing.

Pull the top off the carb, look inside, work the throttle. Whats that? A black screw, lying sideways, jammed up against the needle. The needle is about an inch higher than it should be as a result, and jammed in that position. As a result, fuel has just been pouring into the engine, at the equivalent of about 75% throttle—at idle.

Inside the Mikuni, there is a screw that anchors a pivoting assembly designed to hold the needle down. Apparently this screw came completely unscrewed, and jammed up against the needle, which prevented the needle from moving up and down with the slide. We eventually did manage to remove the jammed parts—with some difficulty. The needle was also seriously bent. We got everything replaced—with the screw tightened with blue lock-tite. Hopefully this will prevent a repeat.

After restoring all of the original parts, the bike once again runs smoothly.

I would like to thank all of those who helped with suggestions.
 
Thanks Brian I've tried everything except the manifold check gonna try that next and thanks for the offer to bring it to the shed but your a little to far across the big river..
 
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