ORIGINAL: Augie11
We've got 2 GP kit built skybolts at our field, both nicely detailed. One uses a Saito 1.00 four stroke ( which has an actual displacement of 1.1) and the other an OS 1.20 2 stroke. Both fly well (we're at 5300 feet) but in my opinion the Saito flys and sound better. The 2 stroke 1.2 is a bit much.
All the engine does is rotate the prop.

and makes some sound.
Zor