Boating Heritage

History of Personal Watercraft: Jet Ski to Sea-Doo

History of personal watercraft: Clayton Jacobson's 1960s prototypes, Bombardier's 1968 Sea-Doo, Kawasaki's 1973 Jet Ski stand-up and the sit-down era that followed.

9 min readBoating Heritage

The history of personal watercraft starts with a motocross rider tired of picking gravel out of his skin. In the 1960s Clayton Jacobson II set out to build a motorcycle for the water, and his prototypes became Bombardier's sit-down Sea-Doo, Kawasaki's stand-up Jet Ski and today's three-seat craft. The contested firsts, the sales boom, the safety reckoning and the four-stroke reinvention are visible in the used market — which is why the personal watercraft and boats for sale reward knowing which era a hull comes from.

Before the Jet Ski: Clayton Jacobson II and the 1960s Prototypes

Jacobson was an American inventor with a motocross habit and, by his own account, a simple grievance: crashing on dirt hurt. Industry histories date his first experiments to 1965, when he began building a small jet-driven craft a rider could straddle and steer like a motorcycle, with nothing below the hull to strike a riverbed or a swimmer. He pursued it two ways: seated like a scooter, or standing at a pivoting handlepole.

Jacobson's first licence went to Bombardier, the Canadian snowmobile maker, for the sit-down design, and the deal barred him from licensing anyone else until 1971. By the time it expired, he had refined the stand-up through seven generations of prototype, by his own account. That is his real place in the story: he made the craft practical, patented it and sold it to the companies that would define it. Which counts as "first" splits by design — sit-down and stand-up reached the market five years apart, under different brands.

Bombardier's Sea-Doo, 1968: The First Production Personal Watercraft

Bombardier launched Jacobson's sit-down in 1968 as the Sea-Doo — BRP's company history still presents it as an industry first, the first personal watercraft sold to the public. It was a two-seater with an air-cooled 320 cc Rotax engine; period advertising called it a "jet-powered Aqua Scooter." To prove the concept, Bombardier's president, Laurent Beaudoin, and his management team rode Sea-Doos from Montreal to New York City — more than 430 miles via Lake Champlain and the Hudson.

The stunt worked; the product struggled. The air-cooled engine ran hot, the flat seat drew comfort complaints, and Bombardier discontinued the craft after the 1970 model year: a limited success ahead of its market. But the blueprint was public — small, jet-driven, ridden astride. When the idea returned, it would return standing up.

Kawasaki's Jet Ski, 1973: The Stand-Up That Named the Category

When Jacobson's Bombardier exclusivity lapsed in 1971, he licensed the stand-up patents to Kawasaki, whose new marine team worked to a charming brief: waterskiing alone, without a boat. Kawasaki Heavy Industries' own history records the result — a 1973 product, code-named WSAA, built at the Akashi works around a 398 cc two-stroke twin adapted from its snowmobile engines. Flat-hull and V-hull versions were trialled; the response put it into mass production as the Jet Ski, and in 1975 production moved to the Lincoln, Nebraska plant, where the JS400 entered full-scale manufacture.

The Jet Ski asked athletic things of its rider — balance, timing, a willingness to fall off — and sold a new kind of fun. It also pulled off the most successful act of naming in marine history: "Jet Ski" was Kawasaki's registered trademark, yet riders applied it to every craft afloat, and still do. Jacobson's role had to be defended in court: when Kawasaki's marketing claimed the invention, he sued, and a jury upheld his libel claim. Kawasaki built stand-ups for decades, but the market was about to sit down.

The Sit-Down Era: Sea-Doo Returns and Yamaha's WaveRunner, 1980s–90s

The turning point came in 1986, twice. Yamaha entered with the WaveRunner — the Marine Jet 500T, a two-seat sit-down that Yamaha's corporate history calls the world's first seated tandem craft, unveiled at the Chicago boat show. Kawasaki answered the same year with the X-2, a two-passenger sit-down it counts as the first mass-produced model of the type. Jacobson, characteristically, was involved again — industry histories record him consulting for Yamaha from 1986. Two makers claiming the same first in one year tells you what buyers wanted: a seat.

Bombardier returned in 1988 with a reborn Sea-Doo — a 580 cc Rotax rotary-valve engine in a V-hull — and by 1990 both Sea-Doo and Yamaha sold three-seaters; Sea-Doo's GT added mechanical reverse and seating enough to tow a skier legally — driver, spotter and skier. Honda joined in 2002 with the AquaTrax; Polaris and Tigershark came and went too. United States sales peaked at roughly 200,000 units in 1995, the industry association records, with sit-down multi-passenger models at about 99 percent of everything sold from the mid-1990s on.

The Safety and Regulation Era

Success at that scale brought scrutiny. Through the late 1980s and 1990s, accident statistics — heavily involving inexperience, speed and inattention — pushed states to regulate personal watercraft as a category of their own, not as small boats. The industry's answer, set out in the Personal Watercraft Industry Association's history, was a model law endorsed by the National Association of State Boating Law Administrators: mandatory boater education, a minimum operator age of 16, a kill-switch lanyard worn when equipped, a life jacket for everyone aboard, and no operation between sunset and sunrise. By the end of 2002, 35 states had enacted mandatory PWC education.

The hardware changed with the rules. A jet craft cannot steer without thrust, so coasting once meant losing steering at the worst moment; makers answered with off-power steering assistance — Sea-Doo's O.P.A.S. arrived with its 2002 four-strokes — and speed-limiting learning keys. The association's case studies show the payoff: between 1995 and 2004, Florida's PWC accidents fell 67 percent while registrations rose by half. One rule from that era still applies — the right life jacket, worn: our best life jackets roundup covers it.

Four-Strokes, Big Hulls and the Modern Three-Seat Watercraft

The final reinvention was mechanical. Two-strokes were light and simple but thirsty, smoky and loud, and in 2002 the shift began: Sea-Doo launched its four-stroke GTX 4-TEC, and Yamaha launched the FX140 that May, which Yamaha bills as the world's first low-emission four-stroke personal watercraft. From the 2003 model year, the industry association records, every manufacturer produced four-stroke models; its 2006 assessment credited them with cutting emissions by up to 90 percent against 1998 craft.

Four-strokes also let hulls grow. The 2004 Sea-Doo RXP 215 was the first production watercraft past 200 horsepower, opening the "musclecraft" era; in 2009 Sea-Doo's iBR introduced the first brake fitted to a personal watercraft; by 2016 its flagship Rotax made 300 horsepower. Kawasaki's range runs to the supercharged Ultra 310, and the stand-up returned with its four-stroke SX-R 1500 in 2016. The market is smaller and pricier than the 1995 peak — sales had levelled near 79,300 units by 2002, at an average above $9,000 by 2004 — but the default product is now a stable, quiet three-seater closer to a compact boat than a surfboard.

What the History of Personal Watercraft Means for Buyers Today

For used buyers, the eras are a field guide. Two-stroke stand-ups — the original Jet Skis and SuperJets — are simple, light and collectible, but they reward mechanical sympathy. The 1990s two-stroke sit-downs are the cheapest way onto the water and the likeliest to need pump and electrical work. The post-2002 four-strokes are the default family buy: quieter, cleaner, easier to live with — and a three-seater can legally tow a skier or tuber in most states, since it carries a spotter. Check the lanyard works, ask about pump and wear-ring condition, and confirm the seating suits your state's towing rules. The same jet-pump lineage runs through full-size boats: our best jet boat brands roundup makes a useful second read, and our history of jet boats tells the propulsion side.

History of Personal Watercraft FAQs

Who invented the personal watercraft?

Clayton Jacobson II is the closest thing to an inventor the category has: his prototypes became both the first Sea-Doo and the first Jet Ski, and a jury later upheld his claim against Kawasaki's competing account. But "first" splits three ways — Jacobson built the prototypes, Bombardier sold the first production craft in 1968, Kawasaki sold the first stand-up in 1973 — and Yamaha's history reaches back to a French patent-magazine design of around 1930. Treat unqualified "invented the jet ski" claims with suspicion.

What was the first personal watercraft?

The first sold to the public was Bombardier's Sea-Doo of 1968, a two-seat sit-down with a 320 cc Rotax engine. The first stand-up — the configuration that made the category famous — was Kawasaki's Jet Ski of 1973. Both trace to Jacobson's prototypes.

When did personal watercraft switch from two-stroke to four-stroke engines?

The first four-stroke models arrived in 2002 — Sea-Doo's GTX 4-TEC and Yamaha's FX140 — and from the 2003 model year, the Personal Watercraft Industry Association records, every manufacturer produced four-strokes. Two-strokes lingered in stand-ups and entry models, but any family three-seater built after the mid-2000s is almost certainly four-stroke.

Are stand-up jet skis still made?

Yes, as a niche. Kawasaki's SX-R stand-up, launched as the 1500 in 2016 and renamed SX-R 160 in 2023, continues, as does Yamaha's SuperJet, running since 1990. They are a small share next to sit-down three-seaters — 99 percent of the market since the mid-1990s — but for riders wanting the 1973 experience with modern power, the stand-up never left.

Every personal watercraft is one of Jacobson's arguments made metal — stand up or sit down, solo or bring the family — and the history of personal watercraft is those arguments getting faster, quieter and bigger. Pick your side, then browse the boats and personal watercraft for sale and take the next chapter home.