Ya - I think the 50cc is way to much for this plane. I know Chip says it'll handle it, but it's overboard (in my opinion). The Saito 1.8 or OS 1.6 will make this a rocket already. The YS 1.4DZ is probably stronger than the Saito 1.8 and not that much heavier. I'd go w/ the YS. You are going to love this plane. I'm just waiting for my 5945 to arrive to finish everything up.