2018 Yamaha GP1800 vs. Kawasaki Ultra 310X: By the Numbers

We see how two PWC powerhouses stack up

The 2018 Yamaha GP1800 and Kawasaki Ultra 310X are two of the most powerful PWC in the industry. Let’s see how they compare.

From the very moment the internal combustion engine was created, people have been on a quest to find more power. We like power, and for many of us, it’s in our DNA. Whether we’re racing against each other, or just ripping along and enjoying the life, we feel a deep-seeded need for speed. If you’re one of us, who views the speed limit as more of a suggestion, and the size of the smile on your face is directly linked to the application of throttle, then you’re probably in the market for one of these machines. The 2018 Yamaha GP1800 and the Kawasaki Ultra 310X are so powerful, you’d swear you were flying over the water. Let’s see how they stack up…by the numbers.

Supercharging In

If we’re talking about power, we’re talking about the engines and both of these powerhouses have some serious muscle under the hood. The 2018 Yamaha GP1800 is billed as a performance racing-series PWC. Of course, that doesn’t mean that you can only use it for racing, but if you’re looking for a competition machine, this might be a pretty good choice. It is powered by an 1,812cc 1.8L supercharged, four-cylinder, four-stroke, Super Vortex High Output (SVHO) Yamaha marine engine. Yamaha claims this is the most powerful engine they have ever put into a Waverunner. It is an extremely powerful and torquey engine that runs through a 160mm high-pressure pump.

Kawasaki is no slouch, either, claiming that the Ultra 310X is the most powerful production PWC currently available. How they get there is through a 1,498cc inline, four-cylinder marine engine with an Eaton Twin Vortices Series, Roots-type supercharger and an air-to-water intercooler. This beast of a motor is fed via direct fuel injection and feeds all its power out through a 160mm, axial-flow, single-stage jet pump. This setup is good for 1,890 pounds of thrust. You’d better be holding on tight when you crack the throttle.

To Hull and Back

All the horsepower and thrust means diddley-squat is you can’t put it to good use in a light and maneuverable hull. It’d be like throwing a Corvette engine into an economy-car frame and hoping you can run NASCAR. Luckily these two PWC have highly-advanced hulls to go along with their powerful engines. The GP1800 has Yamaha’s NanoXcel2 ultra-lightweight hull and deck design. This reduces weight while remaining rigid and strong. The 2018 Yamaha GP1800 can carry one to three riders and has an 11-foot long hull that is four-feet wide. It comes in at 769 pounds dry and is very capable of carving up a course, or handling the chop while you’re having fun.

The Kawasaki Ultra 310X was designed with an extra deep hull that is one of the best in its class for handling rough water. You may not think rough-water handling is important, but you’d want a machine that can handle it when conditions change rapidly, as they often do on the water. The overall length is just over 11 feet and comes in at just under four-feet wide. The curb-weight is 1,051.8 pounds. The 310X also seats three riders. Assisting handling is Kawasaki’s Smart Steer feature that aids in steering and handling when the throttle is suddenly released at higher speeds. This helps you remain in total control when you let off the gas. The handlebars are also five-way adjustable to fit any rider and the Jet Ski has Kawasaki’s Smart Learning Operation (SLO) mode to help new riders get the hang of things before they feel the brunt of the engine’s massive power output.

Storage is pretty different between the two machines. The 2018 Yamaha GP1800 has 24.6 gallons of storage and an 18.5-gallon fuel tank. The Kawasaki has a whopping 56 gallons of storage capacity and holds 20.6 gallons of fuel. Fuel economy modes make sure you don’t burn through the gas too fast, too.

The 2018 Kawasaki Ultra 310X comes in a Metallic Surf Blue and black color combo. It retails for $15,299 and is available at your local Kawasaki watercraft dealership. Head there to check one out for yourself read our full review here.

The 2018 Yamaha GP1800 comes in two color choices – Torch Red Metallic or Team Yamaha Blue. It has a starting MSRP of $13,999 and can be found at your local Yamaha Waverunner dealership. You can also read our full review here.