Started my mojo out with a webra 50, one of the recommended engines, but it ingested a washer and froze up. Yanked a YS 63 out of another airframe. Like the YS so much better than the 2 stroke, but I am one of those guys that put-put around. Love the mojo, it seems happy at any attitude without wanting to snap or do something not asked of it. Something like the QQ Yak 54, but better!!! At the time of buildilng, I only had small electric servos and a bunch of JR digital 200+ oz puppys. Awsome combo, hovers at about 1/3 throttle and goes and stays where you point it. You will enjoy regardless of engine and servos, need good centerilng servos or it will drive you nuts. ENJOY