First of all, this is my opinion and only stems from my personal experience... It seems to me that back in the day of a "2-stroke only" boat motor world, weight was not a factor so the industry (or Coast Guard) came up with a calculation to figure how much power a boat could safely handle without having to consider the weight of the motor. I know there are also maximun weight capacities for a boat but I'm sure that weight is supposed to be evenly distributed and not hanging off your transom. When I went from a 2-stroke 20 HP (that was easily carried with one hand) to a 4-stroke 25 HP (150 lbs that is a strain no matter how I handle it) my transom gained weight and cracked as a result. Now that the transom has been rebuilt (and raised) I still have the weight to deal with which of course makes the transom sit low in the water. I was told last week that a Tahatsu 30 HP 4-stroke weights 200 lbs. Now I'm not sure on the rating for my boat because there isn't a tag on it but I would be willing to bet that it is rated for at least 30 HP. Knowing what a 150 lb motor does to it, I'd be a fool to strap a 200 lb motor on it no matter the HP rating. Do you think a dealer will tell you this stuff? I doubt it. When I bought my motor I asked the dealer if they normally put a motor that big on a 14' boat and he said "all the time". It's all about the bottom line, the mighty dollar and them hanging on what that little label on your boat says the Maximum Horse Power rating is. I believe that there should be an upgrade to the Maximun Horse Power ratings to include Maximum Motor Weight.