I'm teaching myself to fly, with a Limbo Dancer powered by an Irvine 39
2-stroke. It's going well so far...but how can I improve the pick-up of the engine? I appreciate that the carb isn't the most complicated device in the world, but I didn't expect a slight falter before the engine accelerates.No doubt it's the mixture at fault. I'm probably running it slightly richer than I should (a quarter-turn off max RPM). Will leaning it help?
Cheers in advance,
Jim
Sounds like your low end is too rich. This is allowing the cranckcase to load up with fuel and sputter through the mid-range on its way to full throttle. In extreme cases the engine will stall in the mid-range... Try turning your low end needle CW (leaning it out a little) 1/16th of a turn at a time while running your engine... Low ends typically don't require much adjustment if at all, so remember where your original setting is... Hope this helps...
On 12/27/2003 4:41 PM Ted shuffled out of his cave and grunted these great (and sometimes not so great) words of knowledge:
Once you have the low end (for the transition) worked out, don't forget to check the high end. Engine wide open, hold the plane nose up. The engine should not change rpms. If it does, adjust the high speed needle
1/8 turn, go to idle, then full throttle and do it again. Keep doing this until there is no rpm change. If you do not do this there is a VERY HIGH probability of the engine quitting when you try to do a loop, hammer head stall, or any other manuver that will put the nose of the plane high.
Thanks JR, Mike, Ted - makes a lot of sense. I'll do just that.
Jim
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