ORIGINAL: MKnutson
I think the 40cc OS would fly the Tiger Moth just fine! Just put a big dia. flat pitch prop on it to fly slow.
I don't think that the OS would be overkill, but it would be at the higher end for power. Locally a guy flew one, (Tiger Moth), with a Rotomotor 35cc 4 stroke and it was powered ok, but could have used more.
I'm not into marginally powering my planes, that's what they make throttles for.
Mark
Thanks for imput guys.
Pus the Tiger seems to need a bit of nose weight, so the slightly bigger engine will help.
I have 92 inch Ryan STA, witht he OS GT33. Weigh overpowered, but big dia small pitch prop makes it a delight to stooge around at 1/2 throttle.
Interesting the thought that OS will bring out a smaller 4s petrol. I bought the OS 33 , and now have the OS 22. Both Great engines, VERY smooth.
Regards from 'Down Under.