I put a new spark plug in and rode about a quarter mile at low throttle. The electrode looked white-ish, not sure if I really rode long enough. Anyway, I moved the clip from center to one below center. First thing I noticed is it started smoking when it had not done so before. The second thing I noticed was that it wanted more idle. I turned that screw again and again, probably ended up with at least two full turns towards higher idle by the time I was done.
I'm looking for general explanations/confirmation to these two questions:
Why does a richer needle setting make the engine go from no visible smoking to quite a lot of smoking? It's a sure sign that the needle is set too rich, correct?
Why was I able to turn the idle up a lot and the idle just barely got faster. I suppose that too confirms that it was too rich?
So far I can't seem to determine whether the 70 or the 72 jet is better. So, next time out I'm going to try a 75. I'm thinking it will either run a bit better or lot worse. If worse I'll at least know what too high is.
I'm looking for general explanations/confirmation to these two questions:
Why does a richer needle setting make the engine go from no visible smoking to quite a lot of smoking? It's a sure sign that the needle is set too rich, correct?
Why was I able to turn the idle up a lot and the idle just barely got faster. I suppose that too confirms that it was too rich?
So far I can't seem to determine whether the 70 or the 72 jet is better. So, next time out I'm going to try a 75. I'm thinking it will either run a bit better or lot worse. If worse I'll at least know what too high is.