Sept. 22, 2008 – Sporting new technologies

By Jeff Hemmel
Contributing writer
Sea-Doo upped the ante, recently unveiling to its dealer network the GTX Limited iS, a PWC that features a full suspension, braking system and electronic throttle, all essentially networked to the craft’s ECU. Whether consumers will flock to a craft that will retail for $16,499 still remains to be seen. The technologies, however, are clearly pushing the envelope for the PWC market far beyond what has become the industry standard.
Powersports Business was invited to an exclusive sneak-peak of a late-stage prototype in July.

INTELLIGENT SUSPENSION
The concept behind intelligent suspension is to essentially separate the entire rider area — seat, handlebars, even footwells — from the actual hull itself. The idea? To isolate the rider from the shocks normally transmitted through the hull in rough conditions. Sea-Doo designers link the two components through hinged aluminum arms fore and aft, and deliver the cushioning through a center-mounted suspension. Consisting of a pre-loaded spring and shock absorber, it provides approximately six inches of travel for the upper unit, or what Sea-Doo engineers now refer to as the “rider pod.” The craft’s all-important ECU, dubbed iControl, determines a pre-set load for the shock based on the rider weight in the saddle. Switch to manual and riders can make it soften or stiffen to preference on a scale of 1-9.
Even those accustomed to high tech will likely gawk at Intelligent Suspension in action. Hit the start button and the system’s hydraulic pump activates, elevating the rider pod to its full height with a mechanical whir. Ease away from the dock and you can see the suspension in action by simply bouncing in the footwells. It’s only in truly rough water, however, that you fully appreciate the system. During an exclusive test ride arranged for PSB and sister publication Watercraft World, we were able to put a late-stage prototype through its paces on a windswept Montreal lake. We found that, while Intelligent Suspension is certainly no magic carpet that hovers the rider above the water, it indeed takes a great deal of the pounding out of rough water. The entire rider area is suspended, so riders can still stand in extremely rough conditions while the system softens the blows below. At moderate speeds you’ll likely stay comfortable in the seat far longer than on a model without suspension. The system also naturally compresses in a tight turn, mimicking a little of the Sea-Doo HX and XP designs of years past, models that were designed to lower your center of gravity while punching through a corner.
Return to the dock, or just simply desire a lower center of gravity, and the system can be deactivated with a push of a button.

BRAKING AND THROTTLE
Equally radical on the iS is the introduction of the industry’s first OEM braking system. Replacing the former off-throttle maneuvering paddles, Intelligent Brake and Reverse (iBR) instead uses a beefed-up reverse bucket to slow, and ultimately stop, the craft in collision-avoidance situations. Hardly a new idea, but the difference here is that the iBR is tied to that computer brain. Activated by a lever mounted on the left handlegrip, the system first shuts off water flow through the pump for a split second as the reverse bucket drops. Then, dependent upon how hard the operator squeezes the handle and how fast the craft is moving, it ramps that thrust back up, rapidly arresting the craft’s forward motion. Gone are the days when a high-speed drop of the reverse bucket would send the driver over the handlebars, and in its place is a controlled, safer solution. Abruptly squeezing the lever at speed can still cause some spray to come over the bow, but with minimal practice you learn to feather the lever, much like stopping your car at a stoplight.
That same link between computer brain and reverse bucket has further potential thanks to the adoption of electronic throttle control. Now the iS starts in a pretty good imitation of neutral, the bucket redirecting the thrust just enough to keep the craft stationary at the dock. Squeeze the throttle and you’ll move forward. Squeeze the combination brake/reverse lever and you’ll switch to reverse. It’s intuitive, and allows you to keep both hands on the handlebars, along with eyes on the water.
As Yamaha showed last year with the SHO, electronic throttle now means things like cruise control and no-wake modes can be a reality. Sea-Doo allows the cruise control to be adjusted on the fly throughout the entire mph range. Likewise, no-wake mode is not limited, but can be set anywhere from 1-7 mph.

HULL, EXTRAS
The iS features a new construction method for Sea-Doo, one which uses a new material formulation that is said to be 50 pounds lighter than its fiberglass-reinforced (FRP) counterpart. It’s produced in a closed mold, meaning no excessive emissions during construction, and features a ribbed design to enhance strength and structural integrity. It also features a stepped running surface, designed to reduce drag and enhance both top speed and cornering. Other improvements include tilt steering that is lever-operated, and a display that moves with the steering column, rather than become obscured by it. A hinged seat, supported by a pneumatic strut, pop-open fuel fill and programmable Learning Key speed limiter also make their debut, as do retractable mooring lines built into the hull fore and aft.