Small Engines (Lawn Mowers, etc.): 20hp Honda, cigarette package, honda engine

Question
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Followup To
After some fooling around with the choke I managed to get the engine to stay running.It runs very roughly but as it gets warmer seems to run smoother. It is definately running on both cylinders because when I try to start it with one plug wire off it is a no go. During this unusually long warm up period the engine smokes heavily(blue).The smoother it runs over time the less smoke produced. I had the coils off and am wondering the clearance that should be used between the poles on the coils and the flywheel? I used the thickness of a cigarette package. After spending over $300 already with no results I am reluctant to take it back to the repair shop
Question -
I have a 20hp v-twin honda engine(GX620). The engine will only start momentarily on one cylinder. I have taken it to two local repair shops and have gotten it back both times with the same problem. The first time they gave it a general cleaning (carbs, magneto new plugs)and it ran fine in the shop. I took it home and it was no better. The second day I decided to take it to the Honda dealer. They said the engine dyoid needed replacement. I waited five days for the part took the engine home installed it in the sawmill (3hrs work) only to discouver the same symptoms all over again. The only difference I can see is that I am trying to start the engine outside(-3C), and they are working on it in a heated shop. When I remove the plug from the dead cylinder it is soaking with fuel but when I turn the engine over there is fire in the plug.Is it possible for the coil in this cylinder to be failing under compression in cold weather only?
Answer -
Yes, it is possible the plug is failing to fire under compression and in cold weather.  However, the same coil circuit (usually) fires both plugs.  My recommendation is the wire or connector between the coil and the plug has an issue.  Check for a bad connection inside the bad cylinder's plug boot and make sure the wire hasn't chafed against something and is losing spark to ground.  Hope this helps.

Answer
The cigarette pack will get you close but the coil to flywheel gap should be 0.010"  Heavy blue smoke indicates oil consumption...check to make sure the oil level isn't excessive.  Perhaps there is a lot of oil getting past the valve guides because they are worn or the rings are worn and allowing excessive oil consumption.  Hope this helps.