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2024 Kawasaki ULTRA 310LX

$ 21,199


Category: Luxury



Rider capacity









Displacement (cc)




Carburetion Type

Fuel Injected

Cooling System


Engine Stroke





Performance (hp)


Top Speed (mph)


PWR - Dry Weight (hp/lbs)*


PWR - With Rider (hp/lbs)*


PWR - Curb Weight (hp/lbs)*



Width (in)


Length (in)


Height (in)


Dry Weight (lbs)


Curb Weight (lbs)



Weight Capacity (lbs)


Full Oil Capacity (qrt)


Fuel Capacity (gal)


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Oil change (qrt)









Reboarding Step


Just for information purposes!
For exact information, please refer to the manual.
* PWR: Power to Weight Ratio [Rider: 200 lbs]

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If you want to learn about and/or compare the jet skis in the latest Kawasaki Jet Ski lineup side-by-side with other competitor models, we invite you to use our PWC Browser and Comparison Tool!

Keep reading for all the details on the well-known Kawasaki Jet Skis.

We’ve listed their legendary milestones throughout the history of this illustrious brand right here under one roof:

History of Kawasaki Jet Skis

The 1960s:

The Jet Ski brand name belongs to the Japanese company Kawasaki for the personal watercraft (PWC) it manufactures. However, a Norwegian-American inventor named Clayton Jacobson II, was the one who actually invented this incredible machine.

In the early ‘60s, Jacobson was a highly skilled motorcycle racer. But after crashing on the racetrack, he started thinking that there must be a safer way to enjoy the excitement of riding that didn’t involve the risk of falling off and hitting the hard ground.

He came up with the idea of a “motorcycle on the water” and immediately started making sketches that resembled something like a powered water ski. Within a few years, Jacobson had decided to quit his job in finance to work on developing his concept for a jet ski full time. By 1965 the first working prototype had been made.

This first production model was a sit-down Bombardier Sea-Doo, but unfortunately, it never became commercially successful.

Jacobson had an agreement with Bombardier at the time that kept him from taking his ideas elsewhere until 1971, at which time he entered into an exclusive licensing agreement for his patents with Kawasaki that included the development of their stand-up models.

1973: The first production Kawasaki Jet Ski, the JS400 was introduced in 1973. This machine was the first commercially successful PWC in the world and it launched an entirely new sport! These machines offered plenty of power along with excellent maneuverability. Although it took some athletic skills and practice to ride a stand-up Jet Ski, “jet skiing” soon became the trend among watersport enthusiasts.

1977: When the market demanded a more powerful Jet Ski, the JS400 was developed, which was an upgrade on the very popular JS400.

1982: Five years later the JS550 came out, which was the first Jet Ski to have the newly reconfigured, high-capacity mixed-flow pump as well as an advanced 36 HP engine. Technology was advancing at that time and an automatic RPM control system was featured on this model that prevented the engine from revving up too much.

1986: The Kawasaki lineup this year included two models. In addition to the JS550, the JS300 made its debut. Thanks to its lightweight body, the JS300 was the perfect choice for beginner and female riders. That same year, the company released its first sit-down-like Kawasaki Jet Ski, the X-2, which was literally a combination of a stand-up and sit-down model.

1987: This was when the new Kawasaki 300SX and the high-performance 650SX were unleashed on the market. The 650SX had a new V-shaped hull design that proved to be more stable when cornering and also made reboarding much easier.

1989: Kawasaki came out with two exciting new models this year. One was the Kawasaki JET MATE which combined the drive system and engine of Kawasaki’s 650-class Jet Ski models with a boat-like hull with 3 seats. The other new model this year was the 2-seater Tandem Sport, which was the company’s first actual sit-down watercraft.

1990: This is when the sporty Kawasaki 550SX hit the market equipped with a 47-HP engine, a “self-circling” mode, an over-rev-limiter, and a mixed-flow jet pump. The combination of all these features made the 550SX unbeatable in races.

1991: Kawasaki surprised the market this year with another extraordinary machine, the Kawasaki SC. Instead of a regular saddle, the SC came with a side-by-side seat that looked like a tiny couch. The Kawasaki SC was equipped with a reverse system, an adjustable car-like steering wheel, and a fiberglass-enforced hull filled with floatation from to prevent it from sinking.

1992: To satisfy the demand for high-performance Jet Skis, Kawasaki re-introduced the popular X-2 as 750SS. Its fiberglass hull housed a more powerful engine, it had a saddle for two riders, a large gas tank, and more storage compartments. Along with this popular sit-down Jet Ski, the high-performance stand-up 750SX was also launched this model year.

1993: This year Kawasaki introduced an innovative electric trim system that allowed riders to control the angle of the jet nozzle with the touch of a button. Other remarkable upgrades that were introduced this year were the 5-blade impeller and the first dual-carb Jet Ski engine.

1994: The Kawasaki ST was released this year as the first 3-seater PWC in Kawasaki’s fleet. Unlike its tiny predecessors, this machine looked more like today’s huge “boat-like” PWCs. Besides this family-sized Jet Ski, the race-ready Kawasaki Super Sport XiR was also hit the market this year.

1995: This was when the company revealed the first 3-cylinder engine that could produce an amazing 100 HP. Powered by this engine, the luxury Kawasaki 900 ZXi made its debut. Because of the 900 ZXi’s innovative design, it was voted “Watercraft of the Year.”

1995 was also when Kawasaki became the first PWC manufacturer to put together a factory-supported Jet Ski racing team. The company has been heavily involved in PWC racing since the beginning, and over the years, and not surprisingly has won quite a few championships.

1997: Kawasaki unleashed the 1100 STX this year, along with the 900 STX. These machines shared the same nimble STX hull and large sponsons but came with different engine options.

1999: This is when the legendary Kawasaki Ultra series began its run with the emergence of the Ultra 150. Its lightweight 145 HP engine made this machine one of the most powerful models of that time. This latest hull design featured a deep V-shape that ensured an unmatched riding experience on rough waters. Other popular models in the 1999 lineup included an upgraded 900 STX, 1100 STX, and the more advanced 1100 STX-Limited.

2000: Kawasaki introduced its advanced Direct Injection (DI) engine, which significantly reduced oil and fuel consumption. The improved fuel efficiency resulted in a much better fuel range and a longer riding time.

2001: The upgraded Kawasaki 1100 STX D.I. hit the market this year and was equipped with the innovative Kawasaki Smart Steering (KSS) system. This feature was designed to make turning easier in off-throttle situations.

2003: For their 30th anniversary, the Japanese manufacturer introduced many new and exciting models and features. This year’s most talked-about announcement was that Kawasaki had moved towards 4-stroke technology by launching the revolutionary STX-12F, which was powered by a 4-stroke engine. That same year, the legendary SX-R 800 made its debut and completely reshaped the stand-up PWC segment. The carefully designed wide hull made this machine easy to ride, even for beginners.

2007: The all-new Jet Ski Ultra 250X hit the market this year, powered by a 1,498cc, 4-cylinder engine. Boosted by a Roots supercharger, this power plant cranked out an unbelievable 245 HP.

2011: To keep pace with the competition among rival manufacturers for more horsepower, Kawasaki rounded up the performance of the supercharged Ultra series to 300 HP. But to the greatest regret of fans, the stand-up SX-R 800 was canceled after this model year.

2014: Flagship Kawasaki Jet Skis got some additional HP when the Ultra 310 series was launched.

2017: Stand-up Kawasaki Jet Skis made a comeback when the company introduced the all-new SX-R 1500, which was the first production 4-stroke stand-up PWC on the market.

2020: The STX-160 series now replaced the aged STX-15F. Although the top deck and certain features were designed from scratch, this series was still equipped with the same hull and engine as the retired STX-15F.