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#15900
BRIAN MARSHALL
Participant

Take the spark plugs out, turn fuel off, ignition off, open air lever (choke), open throttle fully, and then gently operate the kickstart. You should be able to feel crankcase compression, and hear a plopping noise, like the cork being pulled from a bottle, twice per revolution of the flywheel. If the crankcase compression is ‘missing’, then the engine may have been assembled without cylinder base rings, and it will not be able to draw in any petrol/air mixture. With the plugs back in, and your hand over the carburettor bellmouth, you should be able to feel strong suction as the engine is turned over. If you are not a contortionist, and struggle with that, do it by putting the bike in second gear, and then turn the engine over by turning the back wheel by hand.
Let us know the outcome of these checks, as there are of course other possibilities, such as a blocked primary airway in the carburettor, wrong ignition timing, etc..
Brian