If I knew the OS 91 4-stroke would fly it alright for a sports flyer, that's what I would want to go with. I'm not a spead deamer and I'm not entering it into any contests. Just want to do some "silly" knife edges and maybe roll it around a bit! The 91 weighs a lot less than those larger engines!

I have a goldberg tiger 60 with 6 oz's of weight under the nose to balance it out and my OS 91 surpass 4 stroke pulls that thing around with no problem! I'll bet it weight 8 to 8 1/2 lbs.

"confused charlie"

but i'm not ruling out other engines just yet.....