I have a Raptor with YS80, SB15 and a GV-1, I am running 8.45 to 1 for a gear ratio, TT680 carbon main blades at 1750 rotor rpm on 15% Cosmo fuel 23% synthetic oil. The problem is that when I try to bring the engine down from operating speeds it won't settle into a solid idle, it wants to overspeed. It gets the definite ping ping going as if it is too lean. My needles are currently Low 2 turns, Hover 1.25 turns and High is just shy of 1 turn. My hover and top performance is outstanding, it will maintain a constant rotor rpm at full stick, never bogs. Hover is smooth and steady, with a solid smoke trail. I have removed the carb and cleaned it. Tried an Enya #3 and #4 plug.

Any ideas?

Thanks,
Pete

Sounds to me like it's still too lean on the low speed needle. Remember to that after adjusting the low speed needle, you will need to readjust the mid and high speed needles again. The low speed needle will affect the other needles.
Suptter

Well, I finally got it after another gallon. I took the engine out yet again and completely disassembled it and cleaned everything. There must have been something lodged in the low speed needle path. And I went back to the Enya #3 plug.

It runs very cool, plenty rich, with this 28% oil fuel it has LOTS of smoke. I can run a half tank through it doing FFF and aerobatics after landing I can put my finger on the cylinder for a good 20 seconds without it feeling hot.

My needles end up at Low (just flush), Hover 1.25 and High .75 turns. Seems rich at these settings but is making good power and it's running cool.

Pete

Try to increase the regulator pressure.
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