Fascinating J.A.P V8-Powered Custom Bike Features Vintage Aircraft Technology

The machine we’re about to inspect is in a league of its own, though, as it was pretty much built from the ground up by one Pavel Malanik! As the title of this article suggests, his bespoke marvel was forged around an air-cooled J.A.P V8 powerplant from the early days of aviation – sort of. These vintage, 4.4-liter aircraft engines are rare museum pieces, and each surviving exemplar would cost an absolute fortune.

Consequently, Pavel couldn’t just snatch one from eBay and start building the rest of the bike around it. He instead took a flight from the Czech Republic to England, with the intent of visiting the Science Museum in London. That’s where you’ll find one of the very few remaining J.A.P V8s from the 1900s, and the motor is actually cut open to showcase what goes on inside.

With the staff’s approval, Sir Malanik took precise measurements and as many detailed pictures as he could, carefully studying the engine’s anatomy in the process. Once the research phase had been taken care of, it was time for him to get back to Czechia and start recreating everything from scratch. That, right there, is some next-level stuff to say the least!

Aside from the crankcase and cast aluminum pistons, Pavel fabricated each component in-house through countless hours of painstaking labor. His reproduction of the antique OHV eight-cylinder uses a special type of fuel to suit its low 3:1 compression ratio, and it can make around 50 hp while chugging along at 1,300 rpm. Torque is far more impressive, though, topping out at a brutal 184 pound-feet (250 Nm) lower down the rev range.

All that twisting force requires not one, but two drive chains to reach the rear wheel without breaking things along the way. Even so, these still have to be replaced after a few hours of riding due to wear and tear; precisely the sort of heavy maintenance you’d expect to be required for a V8 beast with more torque than the Triumph Rocket 3.

The hand-built powertrain is, without a doubt, the craziest thing about this two-wheeled masterpiece, but we wouldn’t do Pavel’s work justice if we only talked about the engine. As you might’ve noticed, the motorcycle’s colossal 26-inch front wheel is devoid of any brakes, so all the stopping power occurs at the back.

It comes from two contracting steel bands tightening around internal drums when actuated – a rudimentary setup, for sure, yet one that fits the theme of this build perfectly. Then there’s the hardtail frame which holds everything together. Fashioned by Melenik out of tubular steel, the skeleton encases a custom fuel and oil tank combo up top, while supporting a vintage-style sprung saddle a bit further back.

The aforementioned oil chamber takes care of lubricating the crankcase and cylinders, but a secondary unit (mounted below the seat) is used for the camshaft and valves. In short, complexity is the name of the game on this J.A.P-powered showstopper, even if certain parts of it may seem rather simple at first. The front suspension doesn’t lack intricacy, either, employing some sort of springer design with rocker arms instead of springs.

Up top, we see a braced handlebar with the throttle on the right, where you’d expect it to be, and a second rotatable grip on the left to manually advance or retard ignition timing. There is no front fender to speak of, but Pavel did install one at the rear. Right ahead of it lies a rectangular electronics box, hiding a pinch of modern tech in the form of a tiny lithium battery.

Retro-style Ensign tires hug the creature’s wheels at both ends, the brakes are controlled via foot pedals, and the clutch is engaged by a lever near the rider’s thigh. Rounding out the whole project is a muted, yet appropriate grey color scheme with gold and off-white details on the gas tank. Nickel plating makes an appearance in various other places, predominantly highlighting the stand-out feature powering this incredible build.

Now, the phrase “artwork on two wheels” gets thrown around a lot in today’s custom bike world, but there’s honestly no better description for Pavel Malanik’s mesmerizing one-off. Currently in his sixties, the man started tinkering with motorcycles more than four decades ago, back when Czechoslovakia and the Eastern Bloc were still a thing. All this experience certainly pays off, and it’s what enabled him to create such a spectacular machine.