15-05-17, 07:00 AM
Ok, as the bike appears to run fine under load it's sounding more and more like a metering valve issue.
Hunting is normally 2 main reasons 1, the metering valve is worn or not seating correctly which allows more fuel in and gives you the climbing/dropping (hunting) in revs.
The other is float height, it's possible a float is damaged/stuck, try tapping the float bowls one at a time and see if it has any effect, if it does it has at least given you the faulty carb. There is a third an air leak but you can normally hear these as they have to be quite bad to effect the engine.
Another although less likely due to the hunting your getting is blocked pilot/s. Try this start the bike let it idle for a minute not much longer, now be careful and quick, lick 2 fingers and very quickly tap an exhaust header at the bend as it leaves the head. You will hear/feel a sizzling of the moisture on your fingers if the cylinder is firing correctly anything less than a nice sharp sizzle tells you one or more are cold the cylinder/s isn't firing correct i.e. missing this suggests it's a blocked pilot jet/s. This will again give you which carb is at fault.
Only way to tell is to strip the carb/s but at least you'll know which one/s. You'll only have to remove the float bowl to get at the float, metering valve or pilot jet.
Later