One of the jet skis with the highest horsepower is the Kawasaki Jet Ski Ultra 310R.

Here are the details…

• Model – Kawasaki Jet Ski Ultra 310R
• Engine – 1,498cc supercharged inline 4-cylinder engine
• Horsepower – The engine produces 310 horsepower.
• Top Speed – The Jet Ski Ultra 310R can reach speeds of approximately 67–70 mph (108–113 km/h), depending on conditions and rider weight.
• Features – It is designed for high performance with a focus on speed, acceleration, and handling. The model includes features such as a lightweight hull, sport-tuned handling, and advanced rider aids for enhanced control.

This model is known for its powerful engine and is considered one of the fastest and most powerful jet skis available for recreational use. Always check with Kawasaki’s latest models and specifications, as advancements and new releases may introduce higher horsepower models in the future.