Graded source by source

Where the sport came from

1965 to 2009, from one prototype to three manufacturers. Every entry names the sources behind it and how far they go, and where the sources contradict each other the page prints the contradiction instead of picking a winner.

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1. 1965

   Clayton Jacobson II runs the first personal watercraft prototype

   Likely

   Jacobson, an American engineer, has a working jet-pump personal watercraft running several years before any licensed production craft exists. Every machine on this site descends from that prototype, through one of the two licences below.

   Source: Wikipedia on Jacobson

2. 1968 to 1970

   Bombardier licenses the sit-down patents and builds the first Sea-Doo

   Confirmed

   Bombardier takes a licence on the sit-down design and produces the first Sea-Doo, built from 1968 to 1970. This is the fact that decides every argument further down this page about who built the first sit-down: it was Bombardier, and it was 1968.

   Named: Sea-Doo

   Commonly told wrong. Red Bull's history calls the Sea-Doo the inventor's own first model. It was Bombardier's product built on a licensed design, and the prototype came first by about three years.

   Sources: Wikipedia on Jacobson · JetDrift on PWC history

3. 1970

   Bombardier drops the Sea-Doo

   Confirmed

   Sea-Doo production ends after two years, and Bombardier leaves the market for eighteen. That gap is the most important structural fact in the sport's history and almost every retelling omits it: for the whole of the 1970s and most of the 1980s there was effectively one manufacturer.

   Named: Sea-Doo

   Sources: Wikipedia on Jacobson · JetDrift on PWC history

4. 1971

   The stand-up patents are licensed to Kawasaki

   Likely

   With the Bombardier agreement over, Jacobson licenses his stand-up patents and development work directly to Kawasaki, exclusively. The licence is with Jacobson personally. No agreement between Kawasaki and Sea-Doo was involved.

   Commonly told wrong. Red Bull's history says Kawasaki reached an agreement with Sea-Doo to use the designs. It invents a corporate relationship between two competitors that never existed.

   Source: Wikipedia on Jacobson

5. October 1972

   Kawasaki WSAA and WSAB 400, the first production stand-up

   Confirmed

   Kawasaki introduces the first production stand-up personal watercraft, a modified 400cc two-stroke twin in two hulls: WSAA flat, WSAB deep-V. Introduced October 1972 and sold as the 1973 model year, which is why sources counting model years say 1973 and sources counting introduction dates say 1972. Limited production. It was the only commercially successful personal watercraft for about sixteen years.

   Named: WSAA 400, WSAB 400

   Commonly told wrong. Widely reported as "the 1973 Kawasaki JS400". The craft is right and the designation is not: JS400 did not exist for another few years, and which years is still contested below.

   Sources: Wikipedia on the Jet Ski brand · JetSkiWorld on WSAA and WSAB · Watercraft Journal at 50 years · GreenHulk thread 2008

6. 1976

   Kawasaki moves to end the licence

   Likely

   Kawasaki serves notice to terminate. The dispute that follows costs Kawasaki the exclusivity it had held since 1971, which is the legal event that eventually let anyone else build one of these.

   Source: Wikipedia on Jacobson

7. 1976 to 1981

   Kawasaki JS400, the first mass-produced Jet Ski

   Contested

   The JS400 is where the stand-up stops being a limited run and becomes a product: sheet moulded compound hull, 24.5 hp from the 400cc twin, 244 lb, built at Lincoln, Nebraska. The years are the problem. Three sources say production began in 1976 and one says the designation belongs to 1980, and this site sells parts by model year, so the range above is printed as contested rather than chosen.

   Named: JS400

   The sources disagree, and here is exactly how

   JetDrift on the JS400 · medium grade

   Dates the JS400 1976 to 1981.

   Wikipedia on the Jet Ski brand · medium grade

   Places the JS400 at 1980 in its Kawasaki model list.

   Watercraft Journal at 50 years · medium grade

   1976, full production begins at the Lincoln, Nebraska plant, with the same 400cc twin as the WSAA and WSAB.

   GreenHulk thread 2008 · second-hand

   1976, model code JS400-A, the first mass-production Jet Ski, SMC hull. Second-hand from a dead Kawasaki Canada page, so it corroborates rather than settles.

   What would settle it. A Kawasaki parts microfiche or a factory service manual for the JS400. Model year boundaries decide fitment, and three sources agreeing is not the same as a manufacturer document saying so.

   Commonly told wrong. Red Bull's history dates the JS400 to 1973 and calls it the first commercially popular model. Every source consulted here puts it later than 1973, and the 1973 craft was the WSAA and WSAB.

   Sources: JetDrift on the JS400 · Wikipedia on the Jet Ski brand · Watercraft Journal at 50 years · GreenHulk thread 2008

8. 1986 to 1995

   Kawasaki X2, and the argument about what a sit-down is

   Contested

   The X2 is a 650cc two-passenger craft with adjustable bars and trim, built for nine years, and it is the reason the sport has a sport class. What it is not is settled. One source calls it the first mass-produced sit-down personal watercraft; another calls it a hybrid and gives that title to the 1989 Tandem Sport. Both readings walk past the same fact: Bombardier built a sit-down in 1968, eighteen years earlier, so neither craft can be the first sit-down without a qualifier nobody wrote down.

   Named: X2, JF650-A, Tandem Sport, JF650-B

   The sources disagree, and here is exactly how

   Watercraft Journal at 50 years · medium grade

   Calls the X2 the first mass-produced sit-down personal watercraft, built 1986 to 1995.

   GreenHulk thread 2008 · second-hand

   Calls the X2 a hybrid stand-up and sit-down, model code JF650-A, and says Kawasaki's first true sit-down was the 1989 Tandem Sport, JF650-B.

   JetDrift on PWC history · medium grade

   Neither. It records the 1968 Sea-Doo, which was a sit-down and predates both by eighteen years, and which is what makes an unqualified "first sit-down" wrong whichever craft you pick.

   What would settle it. Kawasaki's own 1986 press material or an owner's manual, which would say what Kawasaki called it at the time. The likeliest reading is that the first claim means Kawasaki's first, but it does not say so and a likeliest reading is not a fact.

   Sources: Watercraft Journal at 50 years · GreenHulk thread 2008 · JetDrift on PWC history

9. 1986

   Yamaha MJ-500T, the first WaveRunner

   Confirmed

   Yamaha launches the Marine Jet 500T, a seated tandem craft, and the WaveRunner line starts here. Yamaha did not invent the sit-down, which was Bombardier's in 1968. What Yamaha did was make the seated tandem runabout commercially successful, and that is the format almost everything sold today descends from.

   Named: MJ-500T, Marine Jet 500T, WaveRunner 500

   Commonly told wrong. Red Bull's history says Yamaha invented the WaveRunner 500. The date is right and the verb is not: the sit-down existed in 1968.

   Source: Yamaha on the WaveRunner

10. 1988

    Sea-Doo comes back after eighteen years

    Confirmed

    Bombardier reintroduces the Sea-Doo as a line of sit-down runabouts, ending Kawasaki's effective monopoly on commercially successful personal watercraft. Everything the sport looks like now starts from the three-way fight that begins here.

    Named: Sea-Doo

    Sources: JetDrift on PWC history · Wikipedia on the Jet Ski brand

11. 2002 to 2009

    Honda AquaTrax, in and out in seven years

    Likely

    Honda enters with a four-stroke turbocharged craft and leaves in 2009. It matters here for one practical reason: an AquaTrax is a discontinued machine with a discontinued parts supply, and anything describing it as a current option is out of date by well over a decade.

    Named: AquaTrax

    Commonly told wrong. Red Bull's history, published in 2021, lists the AquaTrax in the present tense. It had been out of production for twelve years by then.

    Source: JetDrift on PWC history

What this page corrects

The account most retellings copy is a 2021 Red Bull article, and it is wrong in ways that matter here. 6 of the 11 entries above carry a correction to it, marked Commonly told wrong. That article is in the source list below and the build refuses to let any entry cite it as evidence: it is held on file as the thing being corrected, not as a basis for anything.

The omission is worse than any single error. Bombardier dropped the Sea-Doo in 1970 and did not come back until 1988, so for eighteen years there was effectively one manufacturer. Almost nothing about how this sport developed makes sense without that gap, and almost nothing mentions it.

What nobody here has checked

One source on this page is a manufacturer writing about its own product: Yamaha's own WaveRunner history. Everything else is an encyclopedia article or enthusiast media, and no Kawasaki or Bombardier document has been read for any of it. That is why three entries read Likely rather than Confirmed: they rest on one good source each, and one good source is not agreement.

The dates are where this will bite first. Model year boundaries decide which parts fit, the JS400 window is contested above, and nothing on this page should be used to answer a fitment question. The model reference is where those live, and it carries its own warning about the same thing.

Sources

Every row the entries above are graded against. Reliability is not how much we like a source: it is what kind of thing it is.

Nothing on this page is rehosted. Every source is a citation and an outbound link to whoever published it. One of them reproduces a Kawasaki Canada page that no longer exists, which is why it is graded second-hand and why it carries no entry on its own.