G'day rolling_stone, can we call you Mick.
Do you still have Amals.
Tricky little suckers, could be lean or could be rich.
Does the bike start up again, straight away, after it stops, or do you have to tickle again.
If so it may have a slight blockage in the supply to the float bowls.
Firstly, check the plugs, they should tell you something.
Are they dry or wet, black or white. One ok but one wet.
If they are dry then it may be short of fuel. Give the bowls a tap with the handle end of a screw driver
while the fuel is on, this might help with a sticky float.
Remove the fuel lines from the taps, and check for a good flow, then check further along, (inline filters ?),
undo the lines at the carbies and check for flow, if it's all good so far, hook them up and then undo the
removeable plugs on the bottom of the bowls. If the flow is slower than before, then the float needle
and seat may be gummed up.
If the plugs are wet, (flooding), then the floats or a float may be sticking. TAP TAP.
Will the engine rev ok untill it stops. if so probably fuel shoetage.
It's all good fun, so close but so far away, eh.
AC.
Hey Bob,.. On my Mikunis, if there is no lever, only a knob, then up is on.
If there is a lever, then down is on. heheheh.