Originally Posted by bmcd308

50 to 1 ratio - more gas per unit of liquid, so richer mixture than what Kawi recommends

altitude approaching 10K feet - higher altitudes mean less oxygen per unit of volume of air, which richens your mixture.

When your bike was running better, were you running it at sea level?

As asked above, tell us what jets and clip position are in there. There is some chance that the previous owner left the stock jets in and found it to be spooging oil because it was running rich. Kawi jets them pretty rich from the factory.

Because bike is rich, the PO tells you to run 50 to 1, thinking that less oil in the gas will solve the spooge problem, but that actually makes it worse. You thank him and take the bike home from sea level, and now it fouls plugs. No surprise. It was rich at sea level, and then the 50 to 1 mix caused it to get richer, and then the altitude makes it richer still.

If the air screw does not do anything, then you know you have a carb problem of some sort - most likely jetting that is not even close.

Just an idea.