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Sea-Doo RXT-X 300 vs. Kawasaki Ultra 310LX [Video]

Sea-Doo RXT-X 300 vs. Kawasaki Ultra 310LX [Video]

The Kawasaki Ultra 310LX is a purpose-built luxury jet ski, while the Sea-Doo RXT-X 300 is more of a touring ski tuned for performance. Despite this, they often compete in the marketplace.

If you want to compare these machines head-to-head, you’ve come to the right place.

We at JetDrift have compiled all you need to know into this RXT-X 300 vs. Kawasaki Ultra 310LX comparison post!

Sea-Doo RXT-X 300 vs. Kawasaki Ultra 310LX

By the Numbers

Although both are built on a large stable touring platform, the Kawasaki Ultra 310LX and the Sea-Doo RXT-X 300 are vastly different. The latter is classed as a performance jet ski producing arm-stretching accelerations, while the Kawasaki is more like a luxury model featuring a wide range of convenience features.

In terms of size, the Kawasaki measures 140.9 inches in length, 47 inches in width, and 48.8 inches in height. This all-new Kawasaki Ultra platform debuted for the 2022 model year.

Compared to its predecessor, this new hull is longer, more stable, and comes with an innovative top deck design.

The competitor RXT-X features the proven ST3 Sea-Doo hull, the same one on which the Fish Pro Trophy and the GTX touring family are built. This massive platform is 135.9 inches long, 49.4 inches wide, and 45.2 inches high.

Compared to the Kawasaki, the Sea-Doo is not only shorter, it’s also significantly lighter.

The dry weight of the RXT-X is 829 pounds, which translates to a curb weight of 954 pounds. In contrast, the Kawasaki weighs 950 pounds dry, and 1090 pounds fully loaded.

The bulky hull of the Japanese ski offers much better capacities since it can carry 21.1 gallons of gas and 44.5 gallons of gear. This storage area includes a 32.8-gallon regular bow storage area as well as two large gloveboxes mounted on the sides of the deck.

They offer 10.6 gallons of storage space and house a dry box for a smartphone.

Although the storage capacity of the RXT-X is only 26.1 gallons, it includes the Sea-Doo-exclusive easy-access center storage. This innovative design allows you to reach the storage compartment without having to get off the saddle.

This comes in handy on long trips when you have to access your cargo on open waters.

Regarding engines, the RXT-X 300 is powered by a supercharged, 4-stroke, 1630cc, fuel-injected, 3-cylinder Rotax power mill rated at 300 HP.

The power source of the Kawasaki Ultra 310LX is a supercharged, 1492 cc, fuel-injected, 4-cylinder, 310 HP Kawasaki engine derived from the ZX-R motorcycle family.

Both engines are paired with an axial-flow, single-stage jet pump.


Both the Sea-Doo and the Kawasaki come with a wide range of innovative features as standard, including:

  • Electric brake and reverse
  • Color LCD dashboard with Bluetooth connectivity
  • LinQ / MultiMount connection cleats
  • High-performance sponsons
  • Bow storage compartment
  • Glovebox
  • Throttle-by-wire
  • Cruise control
  • Launch control
  • Riding modes
  • No-wake mode
  • Dual mirrors
  • Tow hook
  • Mooring cleats
  • Small windshield
  • Reboarding step
  • Audio system
  • Adjustable trim system
  • And more
Both skis feature an electric brake and reverse system, which is labeled KSRD on the Kawasaki and iBR on the Sea-Doo. These systems are almost identical, except for some minor differences.

Just like other performance Sea-Doos, the RXT-X 300 features the Ergolock system, including angled footweels, adjustable handlebars, and the Ergolock seat.

While Sea-Doo’s Ergolock seat helps riders get the most out of the machine, the luxury saddle of the Kawasaki is tuned for comfort. It offers a comfortable bolstered seat place, not only for the operator but passengers as well.

Both can carry three adult riders with ease.


Compared to the Sea-Doo, the Ultra 310LX comes with some unique, Kawasaki-exclusive features, including:

  • Integrated cup holders
  • Adjustable luxury seat
  • Dual “gullwing” gloveboxes
  • Rearview camera
  • Multi-Mount System for GPS, Fishfinder, Camera, etc.
  • LED running lights in the front bumper
  • Kawasaki Splash Deflectors (KSD)
  • Rear wet storage (0.7 gals.)
  • Multi-mount bars
You shouldn’t forget about the Sea-Doo-exclusive features of the RXT-X, which include:

Performance and Handling

Both the RXT-X 300 and the Kawasaki Ultra 310LX are built on a large stable touring platform.

Compared to race-intended purpose-built performance PWCs, these big boys offer comfortable predictable rides even in rough water conditions.The Sea-Doo is built on the revolutionary ST3 platform, which is often referred to as the industry’s most stable hull:

Despite its touring origins, the RXT-X 300 is tuned for performance rather than comfort.

In terms of performance numbers, the Sea-Doo can go from 5 to 60 mph in about 3.6 seconds while the Kawasaki can do the same run in about 4.5 seconds.

The top speed of these machines is electronically limited to 67 mph for safety reasons, but with a light load and under ideal conditions they can even hit 68-70 mph.

Sea-Doo RXT-X 300 vs. Kawasaki Ultra 310LX Comparison Chart

For your convenience, we’ve compiled the key specs of these skis into this RXT-X 300 vs. Kawasaki Ultra 310LX comparison chart:
SpecsRXT-X 300Ultra 310LX
Displacement (cc)16301492
Brake & ReverseYesYes
Length (in)135.9140.9
Width (in)49.447
Dry Weight (lbs)829950
Curb Weight (lbs)9541090
Fuel Capacity (gal)18.521.1
Storage Capacity (gal)26.144.5
Weight Capacity (lbs)600496
Rider capacity33
This chart is for informational purposes only! For exact specifications, please refer to the factory manual.


The Kawasaki is a true luxury/touring jet ski with many innovative features, while the RXT-X 300 is a touring ski tuned for performance rather than comfort.

Each of these models has its pros and cons, which are as follows:Pros of the Kawasaki Ultra 310LX:

  • More luxury features (headlights, rearview camera, etc.)
  • Unique side gloveboxes (capacity: 10.6 gallons)
  • Larger storage capacity (44.5 vs. 26.1 gals.)
  • More horsepower (310 vs. 300 HP)
  • Tuned for comfort and entertainment
Pros of the Sea-Doo RXT-X 300:

  • More sporty attitude
  • Ergolock seat
  • Lighter weight (829 vs. 950 lbs.)
  • Quicker acceleration (3.6 vs 4.5 sec.)
  • Greater weight capacity (600 vs. 496 lbs.)
  • Easy-access center storage
  • iDF debris free system
  • Closed-loop cooling system
  • Tuned for performance and racing
If you are trying to decide between these skis, don’t hesitate to test ride both to taste the differences.

But as a final word, you can’t go wrong with either!