Looking for options. I have a saito 56 4 stroke and want to put it on a ultimate bipe. Would the 56 be to big for the world models <font size="3" face="Arial, Helvetica, sans-serif" color="#ff0000"> Ultimate 40S. The call for a 4c .48. Anybody know of another model I could use this motor on?

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You would be just fine to put the Saito .56 on the Ultimate. .48 or .56- Not much differentce there... Not only that, but most people over-power a plane anyway! I had TWM Ultimate 1.20 (recommended power 1.20 4 stroke) with an evolution 1.20 2 stroke on it. She flew very nicely with no bad habits! Good Luck- I hope this helps you out!

You'l be fine. that Bipe flys well on a .46-LA 2-stroke so your engine will likely work well. It is a fairly small, light airplane.