79 750SS #1 cylinder dead

V650

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Son had to go get a retro Honda so he has a cb750SS.
Didn't run when we got it.
Starts and runs but #1 cylinder is dead, exhaust pipe stays cold.
Bought a set of Murrays Carbs so that is not the issue.
Has 150 compression across all cylinders.
New Coils, plugs and wires, the old coils had splits on them so figured they were due replacement.
New battery, new starter, new starter relay. All grounds have been cleaned, can't find any funk on any wiring.
Swapped new coils anyway, still same issue. Swapped new plug wires, still same issue.
Has Spark, has spark on all cylinders. Good fat spark on all cylinders.
Took a bore scope camera to the intake side valves are moving.
Took off the exhaust, valves are moving.
The only thing not done is doing a valve adjustment, but I can't see that being so out of wack it won't fire.
So it has spark, has fuel, has compression. How can the timing be off for the one cylinder when the coil gets input and works for the other cylinder.
Kind of at a loss here.
Did a search, but only one post and it was fuel related.
 
You definitely need to do a valve adjustment. If you can't certify the valves are within spec, you can't verify they are closing all the way when they are supposed to.
 
Two things. 1- Why did you buy Murphy carbs? 2 - Don't assume that it is not a fuel problem.
 
Two things. 1- Why did you buy Murphy carbs? 2 - Don't assume that it is not a fuel problem.
The stock carbs were pretty bad, didn't have stock air box, my son wanted to keep this bike forever, and I read about Murray carbs and thought they would be worth it. Don't see it being the carbs, they are clean, 1 carb works 2 cylinders. Since the other cylinder is working, can't see it being the carb. It's getting fuel, and it still doesn't do anything with starter fluid.
 
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