Converting a Jet Ski Into a Motorcycle Ain’t Easy, But It Sure Is Fun
It’s dangerous and impractical, but aren’t most fun things that way?
It's often contended that stand-up jet skis should really be called boatercycles—or did I imagine that? They do bear some passing similarities to a two-wheeler, inspiring one YouTuber's ridiculous road-going build.
The video comes to us from Bikes and Beards, with the group purchasing a humble old Kawasaki jet ski for just $1,000. The plan was to turn it into a running, riding motorcycle suitable for use on the road. As it turns out, though, that's easier said than done. Engineering challenges were obvious from the drop, like finding a place to put the rear wheel and figuring out how to hook up the jet ski's weird steering to a wheel up front. In any case, it's significantly harder than doing a similar conversion to a sit-down jet ski.
The first step in the build was to gut the personal watercraft. The engine, fuel tank, and waterjet were removed in just 30 minutes, leaving an empty shell to work with. A Say Yeah electric motorcycle from Amazon was then pulled apart to donate its drivetrain to the build. Its rear-drive hub motor setup delivers around 4 horsepower, running off a 72 V battery pack. The rear hull of the jet ski was notched to fit the wide rear tire. Up front, the hull was similarly cut out to make room for a front wheel and a pivot for steering. Speed wobbles were an issue, but some judicious use of ratchet straps solved that in the end.
Ergonomically, it resulted in an imperfect setup, forcing the rider to stand delicately in front of the rear wheel while crouching slightly to hold the handlebars. Riding the unstable craft apparently takes some practice to avoid simply toppling over. Much of this is down to the cable-based steering setup that turns the wheel the opposite way to the handlebars. However, once mastered, it actually carves on land quite elegantly, in much the same way as a stand-up jet ski on water. Funny, that.
As is the norm, the video then shows the suspensionless jetski taking part in various escapades, from driving on grass to visiting the Chick-Fil-A drive-thru. A top-speed run got the wheeled jet ski up to 45 mph. As expected, the ersatz motorcycle also drew attention of law enforcement by virtue of its lack of plates, registration, and basic safety equipment.
We wouldn't expect this form factor to catch on anytime soon. It's dynamically poor compared to regular motorcycles, and remarkably difficult to ride. Nonetheless, it's fun to see a jet ski take to the streets for the novelty value alone.
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