This boat has a 17" transom which accomodated the '70 Evinrude 25 tiller. However, since newer motors mostly come in 15 or 20 inch lengths, and also since it sat pretty low in the rear (as a tiller), I looked and found a great deal on a 25hp 20" Merc two stroke that was light and with minor modifications, fit the boat. The transom will have to be raised a few inches. Should not be a big problem (so we thought).