There is so much design and engineering on the bike it looks shockingly complex even by today’s standards. “I spent three months just working with a CAD program to design the bike and its parts. Many of the parts started out as billet that were CNC’d and then sandblasted to look like they were cast,” Keiji said. Each wheel is made from three separate pieces. For the front wheel, he made two complete wheels that he designed on the CNC machine then he cut one side off of each wheel and welded each side to a third, center rim section. He followed the same procedure for the rear wheel. Every single weld was ground down and polished so none of the places where metal was joined is visible.

One example of the detail-oriented work is the frame construction. The frame appears to be pieced together with aluminum tubes and angled sleeves that are bolted together. In reality, the frame is welded just like a traditional frame, but all the welds were ground down and clamshell-style sleeves were custom fit over each joint. Every aspect of the bike is intricate, including the wheels. It took him another four months to build the bike, but then he’s got a few really good employees that helped him fit the custom parts together and assemble it.

S&S sent Keiji a SH motor for Nautilus, but when he returned to Wisconsin for the anniversary it barely resembled the way it looked when it originally arrived in Japan. Internally the motor remained stock, but the exterior received the full Hot-Dock treatment. The external oil lines to the heads are faux (because the S&S gets plenty of oil through the push rods) but Keiji said Harley’s Shovelhead required external lines and he liked that detail. He also designed the rocker covers to look like a GP racing bike from the ‘70s, Honda’s CR 750 built with a dual overhead cam. Directly behind the motor is a BAKER Drivetrain 5-speed RSD transmission chosen for its high bolt-to-external-surface-area ratio.

Like many overseas builders, Keiji had to have his bike finished well before the date of the anniversary because it still had to travel halfway around the world so it could be part of the show. Thankfully, the show judges were able to see and appreciate the enormous amount of time and effort that went into Nautilus. The bike won the Best of Show at the event, and the majority of the builders agreed that Keiji had easily put in the most effort — and that’s saying a helluva lot.

Special thanks to Chica for translating Keiji’s Japanese and the author’s English.