ORIGINAL: waynem
I have a U.S.41 engine. The manuel that came with mine says that it is 3 Horsepower. The best prop that I have run is the 18x10. I tryed a 20x6 and 18x12 and liked the 18x10 best. It turns about 7200 R.P.M.s with that prop. Hope this helps. Wayne
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I believe I was misremembering the Quadra Q35's advertised horsepower rating (2 HP). I doubt that any USE 41 ever actually produced 3 HP, but that does not mean that they were not good engines for the price. I bought my original USE 41cc engine because it looked a lot like my old Q35. Remember when the Q35 was selling for $89.95 at Tower Hobbies? <G>