Abstract: A GPS-fitted small watercraft in which one or more GPS antennas are attached to the watercraft in a manner that provides good protection from waves and good signal reception. For a watercraft having a hull member and a deck member joined together at their perimeters, with a gunwale formed at and protruding outwardly from the joined perimeters, the GPS antenna(s) is mounted inwardly from the gunwale on the deck or hull member. Alternatively, the GPS antenna(s) may be mounted to an outside or inside surface of the deck member, on a pad located on a set of handlebars, near a grip of the handlebars, atop or inside a small cargo hatch, on a hatch beneath the handlebars, on a grab bar behind a seat of the watercraft, on a top surface of a bulwark, or on a side wall of the watercraft between the gunwale and a chine of the hull member, either on the inside or outside.

Abstract: A personal watercraft sponson arrangement has sponsons that are configured so as to improve buoyancy and stability upon leaning. The sponsons are designed to be detachably affixed to the hull of the watercraft through the use of a coupling system.

Abstract: A personal watercraft exhaust system, hull underplate, and speed sensor and sponson arrangement. The exhaust system for the engine provides a compact assembly that incorporates a pair of expansion chamber devices on opposite sides of the tunnel to provide a water-trap effect, effective silencing, and still clear storage compartments of the hull. The sponsons are configured so as to improve the buoyancy and provide stability upon leaning, and the underplate mounts a speed sensor to the rear of but below the jet propulsion unit discharge so as to provide a good speed signal and to protect the speed sensor.