try advancing the initial timing 5 to 10 degrees,(just for the test,reset after leaving).for idle failures, be sure the throttle valve (butteryfly) is not uncovering more than half the idle port.those with later carbs set your idle speed at the air bypass screw. if your waiting for the test in the line up,keep the revs up 1200 to1500 to build up heat,colder motors are more likely to fail. were lucky here on the rock....no testing.