Chris is absolutely right. Start with smaller prop. I have an engine that says use a 26x10 but that is too much prop and I am breaking in the engine with a 24x10.
I have put the 3w-42 on a 1/4 Lanier CAP ARF. It has 80.5 inch wingspan and came in at 16 pounds. It pulls the CAP around with authority. I have not gotten too much gas through it before an accident with the ground. It came up and "Smacked" the plane. I have it 80% rebuilt and doing it better this time. The engine being rear carb was not done well to start with, I am fixing that.

I am also switching to the new 3w clear oil additive that Cactus Aviation has introduced. Less black stuff on bottom of plane. I used High Quality Honda Racing oil.

The 3w with 24x10 prop is a 3w-85B2 on Hangar9 CAP arf. Fabulous plane!! Hmm see my pics in member picture section.

Good Luck,
hal
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