The hyperactive yelp of a Kawasaki superbike and the whisper of Nissan's Leaf EV have absolutely no business cohabitating—that much you already know. One is the epitome of the progression of internal combustion engines over decades of development while the other sits at the opposite end of the spectrum and represents the direction of the automotive market, yet someone saw fit to combine the two.

That someone is Derek Young, a certified DIYer who also happens to be an engineer, and who finds the time to judge prestigious Battle Bots competition. What he's built wasn't done so on a whim, but carefully planned out before a single wrench was turned and, yes, he meant to use a 3,700-pound modern vehicle. You've seen other sportbike-powered cars completed in the past, usually based on a lightweight vintage chassis and more often than not, lacking a reverse gear option. This exercise would be based on something more current and already packing an electric motor.

Having grown up glued to Formula 1's V-10 era, Young found that the sound of a high-revving engine was far more satisfying than a V-8's grunt or turbo's whistle. Eventually, a friend would introduce him to a CBR600F4i where a quick blip of the throttle brought with it a rush of screaming high redline memories from those F1 days. "I did ride motorcycles for a brief period, but they weren't for me," he says. "I wanted to have my own car that revved like a superbike. After having seen many swaps in the smallest of cars as well as a handful of motorcycle powered oddities at the 24 Hours of Lemons, I decided to devise a way to get a superbike engine to work in a larger and more modern vehicle."

Jot down set of bullet points on a whiteboard regarding this whole thing and it doesn't really make sense, but have Young lay out his thoughts, and the I.C.E. x EV equation quickly defends itself. He tells us, "the EV powertrain would provide the torque to get a 2,000 pounds (or more) car off the line without destroying the clutch and could provide a reverse as well. With 100 hp of EV front drive and a modern superbike motor, this dual motor, AWD scheme could move a not-so-micro car along nicely." This in lieu of using an older Civic, for example, and having to build an EV system around the front axles and still figure out a way to incorporate a rear-mounted bike engine that play nice with one another.

At the time, Young already owned a Chevy Bolt, but its value was far too high to start heavily modifying. He also had a Fiat 500e but found that a third of the battery runs into the trunk of the bite-sized chassis. A deep dive into EVs found that a first-generation Leaf's EV system stops short right where the rear seats are and its cargo space was enough to fit, say, a motorcycle engine. "It also helped that at the time they could be bought for very little money," Young notes. For just $5,000, this 2013 model with just 38,000 miles and a half dead battery was his, followed by the purchase of a crashed but still properly running 2009 Kawasaki ZX10R.

You get the Kawasaki and Nissan combo, but what's with the Lexus mention? "I chose a Lexus IS350 rear subframe and suspension due to its track width, wheel bolt pattern, factory coilovers, and small footprint," he adds. With the rear of the Leaf stripped out and the Kawasaki engine awaiting its next assignment, Young used $1,000 worth of camera equipment and a process called photogrammetry  to extract precise dimensions (because engineers 'gonna engineer). "This was the major breakthrough that allowed me to design all the critical components in advance in Solidworks before a single part was made," he adds. "This made the parts not only manufacturable by CNC processes, but they would also fit together correctly on the first try."

The detailed pre-planning paid off when Young swapped the Lexus subframe into place over a single weekend. He drove into a borrowed space, without a lift mind you, removed the Leaf's rear and began installing the Lexus frame and custom structure that consisted of laser cut tube and plate. He notes, "I hired a mobile welder to come tackle the structural welding on that Sunday and I drove the car home Tuesday morning." The following weekend, Young borrowed a lift at a friend's shop and installed the ZX10R engine into the rear in just one day, then headed home to finish buttoning up the swap in his driveway. "The car was drivable for all but five days during this whole build. Having an always working EV powertrain up front made this possible and with no fixed parking spot in San Francisco, it was a requirement," he adds.

From the outside, the only visual cues that something isn't quite right with this Leaf is its slightly altered ride height and Nexen N'Fera-wrapped Enkei TS-5, a subtle gurney flap along its hatch top to create a low-pressure area to help with exiting air, and, oh yeah, the huge 3D printed scoop that took over the right rear window. That inlet is sectioned to allow air to pass through to a Honda Civic radiator and to provide a rush of fresh air to the individual throttle bodies. Put your glasses on and note the rear hatch has been cut to create vents that allow the hot air to escape and on the driver's side vent, a 1.75-inch exhaust pokes through. The factory black hatch does a good job of disguising the heavy modification.

Lift that hatch and now engine cover and the ZX10R rests in all its glory right alongside the Kawasaki's fuel tank. That's right, with all the space available, the actual tank was mounted rather than resorting to a fuel cell, and a fill neck was routed through the C-pillar to confuse the hell out of people at his local gas station. On either side of the motorcycle bits and pieces you can see the custom shock towers that now house BC Racing coilovers and help bridge the Lexus subframe to the Leaf.

The factory gauge cluster is still intact and provides feedback on the EV front half, while a full-time camera is aimed at the Kawasaki's tachometer and relayed to a dash-mounted monitor. A custom sequential shift lever works with the ZX10R transmission and offers split second ignition cut for lightning fast, no-lift upshifts while the Leaf's single-speed trans is still employed for EV operation. Perhaps the best part of all of this is how Young designed the front and back half to work independently or as a team. A flip of the switch initiates full EV mode, its 100-hp motor enough to move the car around town. Another click and the future is a thing of the past as the 174-hp ZX10R takes over.

Additionally, there's a third option available, which mates a strictly EV and motorcycle-derived internal combustion engine together in a way that no one ever intended. The result is 281-hp transferred through all four wheels and with its 51.5 front and 48.5 rear weight distribution, provides ample joy from behind the wheel. "The first drive occurred in late December and the exhilaration of banging through the gears and having the stock EV system working in concert with the screaming 13,000-rpm I.C.E. was indescribable," he says. "The car was legitimately quick (5-60mph in ~5.5s) and after dealing with some initial teething issues, it had its first outing to a Cars and Coffee in Menlo Park in March 2022. I discovered there that people loved this weird thing I had created, and after driving up to Skyline Blvd in Woodside, Calif., via twisty mountain roads, I discovered I loved driving it too."

It's not over just yet, as it's continually being enhanced with suspension parts, larger brakes, and a few cosmetic additions. "It's been a real joy to build with every design problem an opportunity to make something completely new," he says. "I love showing it to people and seeing the excitement it generates. I hope to inspire other skilled people to take on audacious challenges and use technology that is now available to us all to build things the world has never seen before."

Engine OEM EV front; Kawasaki ZX10R swapped rear; custom engine cradle, side-mount intake; 1.75-in. exhaust; ZX10R resonator and exhaust servo delete; Honda Civic radiator; Mishimoto 1.3 bar cap

Power 281hp combined using engine and electric motor

Drivetrain original LEAF 1-speed in the front; ZX10R 6-speed sequential in the rear; custom sequential shift lever with ignition-cut clutch-less no-lift upshifting, custom clutch pedal; sealed chain drive Quaife ATB Honda Civic application; D.D.D 530 ZVM-X super street series chain from engine output to differential with idler and adjustable tensioner sprockets; final chain ration 15:56; PBI custom sprockets; Dutchman Axles; Lexus outer CV joints; Honda inner tripods

Suspension BC Racing DS coilovers for Nissan Juke application front, Lexus IS350 application rear; IS350 rear subframe, rear anti-roll bar; custom shock towers and associated structure

Braking LEAF 2-piston sliding calipers front; IS350 single piston calipers rear; vented rotors front/rear

Wheels & Tires Enkei TS-5 18x9.5 +38; Nexen N'Fera SUR4G 255/35

Electronics SkyRC GNSS Performance analyzer; camera to monitor ZX10R gauge displayed on dash screen; Ruggeduino microcontroller monitoring analog LEAF throttle pedal; Dynamixel XM430-W210-R via RS-485 to actuate ZX10R ITBs as drive by wire; mode selector to chane driving modes between EV motor only, gas engine only, or hybrid

Exterior custom gurney flap on hatch wing; 3D printed ABS radiator cooling scoop in passenger side window; Honda Clarity "plug-in hybrid" badge

Interior rear seat delete; custom rear compartment partition; OMP pedal covers; modified/narrowed brake pedal; HP Multijet Fusion 3D printed shift knob

Thank You #1 thanks to my very supportive wife Gillian, and my sons Alistair and Graham.  Huge thank you to Ian Moore, Ryan Hollowell, Greg Dachs, Ronen Sarig, and Mike Rosenzweig who all assisted in the build with tools, time, space, energy and/or insight.  Inspirational and technological thanks to superfastmatt (whose Youtube projects convinced me to build up my own 3D scanning workflow), r/photogrammetry (whose knowledge helped me get rolling in photogrammetry).  Supplier thanks to Sendcutsend, OSHCut, Fictiv and Precision Tube Laser who have made one-off CNC cut metal parts within financial reach of the amateur builder, McMaster-Carr and Misumi who have unparalleled mechanical component resources for CAD users, and Amazon.com for their massive assortment of off-brand tuner components and generous return policy.