ORIGINAL: moto-x
Personal preference, OS 46ax. You won't be sorry while flying the trainer and have a good motor when you step up to something more advanced.
ORIGIONAL:Alan0899
G'day Mate,
I wholeheartedly support Moto-X's endorsment of the OS 46AX, ya can't go wrong, don't go for cheap, it will cost ya in frustration, in the long run.
OS engine quality is decent I can't disagree with that, BUT they are overpriced in my opinion. A fourty size engine, even a ball bering engine, shouldn't cost over a hundred bucks. I would look into the Tower Hobbies engines. If you treat them right (as you have to do with any engine) they are as good as the OS engines. If you want real quality buy a Jett, but it'll cost you about $300 bucks.
Tower .46 ball bearing - 1.75 HP/ 16.9oz. $79.99
OS .46AX 1.65 HP/ 17.2oz. $109.99
I know which one I would buy.
Darren