Not without it on the bike really. The way to test/ prime it would be when on the bike, hold it full open when you start the bike and use a clear line like shotti says. I wouldnt premix personally because the main jet isnt set for premix and so you'll be getting wrong mixtures. A dribble of oil in the spark plug hole and kicking the engine over without the ignition on to would suffice to prevent any extra wear on the barrel. Tbh there would be enough oil in there stil anyway to cover that brief few seconds anyway.
