The Kawasaki Ultra 310LX is the supercharged flagship of the Ultra line and one of the most powerful jet skis on the market. Its 1,498cc inline four-cylinder engine, inherited from Kawasaki sportbikes, makes 310 horsepower. The current platform, launched for 2023, brought better fuel efficiency, a more stable hull, and a larger touchscreen, with smart steering assist, smartphone connectivity, and a good sound system. It seats three and suits both novice and expert riders.
Performance
The Ultra 310LX is built around a 1,498cc supercharged engine making 310 horsepower, fed by a 160mm jet pump and a single-stage impeller running up to 16.8 psi of boost. That gives a top speed of about 67 mph and 0 to 60 in under four seconds, depending on rider weight and water. Fuel range runs about 100 to 110 miles depending on conditions and how you ride. An electronic trim system lets you change the trim angle on the move to improve handling and stability, and it handles rough water and heavy waves well. It competes with the Yamaha GP1800R SVHO.
Safety
The Ultra has a braking system that engages when you drop the throttle for quick, controlled deceleration, plus electronic cruise control to hold a steady speed. There is an emergency stop switch and a handlebar-mounted lanyard for instant shut-off, and a Smart Learning Operation mode that softens the power for new riders. Revised sponsons (the fins along the hull sides that grip the water in turns) improve high-speed handling and stability.
What makes it different
Kawasaki Launch Control Mode optimizes the trim automatically as you accelerate, with modes for a single launch or repeated launches. Electronic cruise control holds a set engine speed at the push of a button, so on long runs you can rest your throttle hand. The Ultra deck is 200mm longer than the standard rear deck, which gives a larger staging area for water play and more storage, with Multi-Mount Rails for adding accessories.
Storage and capacity
This is where the Ultra stands out. The 21.1-gallon fuel tank is one of the largest in the class, and total storage is 44.5 gallons. It splits into a large front compartment, small wet-storage units at the back of the deck, and two gullwing gloveboxes on either side, with a dry phone box, a USB charger, and a 12V outlet. If you pack heavy or ride with three, the Ultra carries more than anything else here.
How it compares to the Sea-Doo GTX Limited 300
Both are luxury touring skis, but they go about it differently. The Ultra is bigger and heavier, at 140.9 inches long and about 1,090 lb on the water, with the most storage in the class. The GTX Limited is shorter, broader, and much lighter, around 974 lb curb weight, and it uses the ST3 hull for industry-leading stability and an easy-access center storage bin you can reach from the seat. The GTX runs a supercharged 1630cc Rotax triple at 300 hp; the Ultra runs the supercharged 1,498cc Kawasaki four at 310 hp. Both drive a single-stage axial-flow jet pump.
Accessories
Kawasaki sells a Vacu-Hold cover made for the Ultra ($313.95), a Quick Access Storage Bag ($73.95), a Stern Bag for extra storage ($309.95), and a registration sticker set ($22.95). A towable cover protects the ski over long trailer trips. The waterproof audio system handles marine conditions, and accessories include a GPS mount, fenders, dock lines, riding gear, storage covers, and anchors.
Is it worth the money?
The Ultra 310LX is one of the most powerful and well-equipped jet skis you can buy, with a 67 mph top speed, smart steering, cruise control, and a waterproof audio system, and the comfortable seat and riding position let you stay out for hours. The drawbacks are the weight, near 1,090 lb, which makes it hard to move on and off the trailer and can affect handling, the thirstier supercharged engine, the high-end price, and the engine note that some owners find louder than expected. If you want the most power, the most storage, and the luxury kit, and you can live with the weight and the cost, it is a good buy.