Ok, so I just rebuilt my z440 sno pro(top end job) and put it all back together. It started up and ran really bad. I ended up finding out that the clutch side piston is not firing. Both cylinders have 150 psi and th carbs are cleaned out. Also there's new fuel lines on the entire sled. I switched carbs and the same thing happened. Eliminates fuel problem. Like I said compression is great. I swapped the spark plug wires around and the same thing happened. I'm going crazy trying to figure this out. Any help would be greatly appreciated!