I would not put a 5hp outboard on a M 15. It's more power than you need, but more importantly it will make the stern squat which ruins performance. In addition, it may cause problems with your transom, such as, causing spider cracks or worse. Bert M 15, Zephyr ************** Looking for a car that's sporty, fun and fits in your budget? Read reviews on AOL Autos. (http://autos.aol.com/cars-BMW-128-2008/expert-review?ncid=aolaut000500000000... )