I am planning to build a Sig Hog Bipe and am torn between installing a TT 61 2 stroke or a TT 91 4 Srroke . I have a TT61 in a Four * and love it. Starts with one flip by hand and runs great. Have never had a four stroke and other than a good sound and some gas economy, don't see much advantage. Would like to have others thoughts on this plane/ motor combo. Fred123

I had a Hog Bipe with a ST .75 in it and it flew great. Several others at the field have .91 four strokes and they fly great too. My next Hog will have a Saito .91 in it.

I've had 3 Hog Bipes. In the 2nd one that I had I originally mounted an OS 61 FX (2 stroke) in it. It flew ok, but was kind of weak really. Plus the sound was just not right. I pulled that off it and put an OS 91 4-stroke. Bingo!!! The perfect motor. Swinging a bigger prop really does this plane justice. And that 4-stroke rumble!!! You just can't beat that. Definately go with the 4-banger