Re: virago only fires on one cylinder

I have a 1982 XV920 with the same problem. No fire in the front cylinder, but after the bike warms up the front  starts to fire intermittently. I checked the coil resistance, coil wire and cap: all within specs. If I pull the coil wire and put in a plug I get a thin purple spark across the gap.

The joint at the right muffler leaks a fine gas vapor and the pipes blow a fine white smoke which smells like gas. My petcock diaphragm is shot so I have to pinch off the fuel line when I shut off the engine. I think I'll rebuild the carbs next. Anyone know where I can find the beginning adjustments? Also, besides the float level, what could cause too much fuel in the cylinder?

Thanks
George