How It Came to Be: Yamaha's 250 V Max SHO was introduced specifically to target the hard-charging bass- and bay-boat markets. Yet, the 4.2-liter four-stroke pulls some of its coolest features from industries well outside the marine world. Take, for instance, its plasma-fused sleeveless cylinders. These have been used for years in piston aircraft engines and over-the-road diesels, engines that are designed — much like outboards — to satisfy longhour operation with an emphasis on durability. Yamaha engineers saw the similarities and acted. The SHO's new cylinders replace steel sleeves and provide a durable surface for the piston rings, while reducing powerhead weight and optimizing displacement. But the plasma technology was only part of the equation, as Yamaha engineers took additional steps to trim precious weight. The alternator, for instance, is 5½ pounds lighter than its predecessor, yet it packs the same punch. The engine also uses a mufflerless exhaust system, eliminating further pounds. "It just wasn't really necessary," says David Meeler, product marketing information manager.