Hi MickyD,
Have you done a visual check of the primer function. Does it give a good squirt of fuel when you push the primer? Is the manifold loose or leaking? When you prime it with aerostart or something similar does it still need 6 or seven pulls to get going? Is the plug gap set correctly?
If all of the above is working correctly then i would suggest checking the valve clearances and adjusting accordingly. Checked cold, Intake 0.05-0.07, exhaust 0.07-0.09 inches.
Try that and let us know how you go.
Cheers, Ted
