Motorcycles are unique conveyances defined largely by their engines – they are motorcycles, after all. The choice of engine in a bike dictates the chassis that must hold it, which has a direct input on the size and weight of the vehicle. The engine also – more than any other motor vehicle – provides a disproportionate amount of character to the riding experience.
Of all the motorbikes that have roamed the world’s roads, almost all of them have engines with four cylinders or less. A few six-cylinder bikes (from Honda, Benelli, Kawasaki and BMW) have added special flavor through the years, but they are costlier and more difficult to package.
Sixes are sweet, but perhaps no other engine configuration is as appreciated in America (and Australia, too) like a V-8. For decades we’ve loved ’em in our muscle cars, and their allure also extends to pretty much any vehicle with a V-8 powerplant. We love the way they sound, whether from the traditional cross-plane crank design most familiar to us in American cars to the more exotic flat-plane crank layout like in a Ferrari V-8.
Earlier this week we reported on the Australian-built PGM V8 that uses a pair of Yamaha R1 cylinder banks to create a 2.0-liter V-8, and that brought up the subject of other motorcycles that have been powered by V-8 engines. Of the ones I found, I’ve culled them down to my 10 favorites. Bonus points for not using an existing car engine, so all but two on this list feature motors that were engineered mostly or entirely by their creators. I’ve included video clips of each (but one) so your ears can appreciate the engines as much as your eyes will.
The original gangsta V-8 motorcycle was the creation of motorcycle, engine and aviation pioneer, Glenn Curtiss. It was powered by a V-8 of his own design and plopped into a suspensionless chassis that looked as much a bicycle frame as a motorcycle, as might be expected at the turn of the 20th century from the former bicycle racer.
The air-cooled V-8 displaced 4410cc (269 cubic inches) and was said to produce 40 hp. It was enough to earn Curtiss the title of “the fastest man in the world” when he rode it to 136.7 mph in Ormand Beach, Florida, in 1906. Car drivers went faster a few years later, but Curtiss held the motorcycle speed record all the way until 1930. The record-holding bike can been seen at the Smithsonian Institution.
Unfortunately, I was unable to find any film of the Curtiss V8 in operation, so we can only imagine what it might’ve sounded like roaring to 130 mph like it did 111 years ago. But the video I’ve included here includes some appreciated detail shots of the first monster bike.
Of all the V-8 engines ever produced around the world, none are as ubiquitous as the small-block Chevy, so it was no surprise when a power-hungry motorcyclist built a two-wheeled contraption around one. Enthusiast Monte Warne took that design to a production level when he founded Boss Hoss Cycles in 1990, manufacturing kits for installing a customer’s Chevy motor, and production bikes began emerging in 1996.
I was tempted to leave out Boss Hosses from this list because of their adoption of an existing car motor (and automatic transmission) to a motorbike, which is a very simple way to invent a V-8 bike. However, the sales success of the Boss Hosses make them impossible to overlook. Production of the ridiculously large (more than 1000 pounds!) and powerful (currently rated at 445 hp and 445 lb-ft) machines obliterate the production numbers of all other V-8-engined bikes ever made. Apparently, more than 4,000 had been sold through 2006, and that number has surely added several digits over the past decade.
They’re crude but wicked, and that’s enough to please many Americans for which there’s no substitute for cubic inches. More info at the company’s website. Tire smoke and obnoxious music in the video below.
Continuing and ending the theme of car-engined motorcycles is this outrageously wild creation from Ludovic Lazareth that uses a Maserati V-8. Of note, it’s not even the Maser motor that is the craziest part of the design, it’s the fact that it has four wheels but leans in corners, as each wheel is mounted to an individual single-sided swingarm.
As brazen as the LM is, it wouldn’t make this list without a V-8, and here we’ve got 4691cc mill producing a claimed 470 hp at 7000 rpm and 457 lb-ft at 4750 rpm. The motor is a 90-degree arrangement with a cross-plane crank design. In a Maserati Gran Turismo, the engine must carry about 4100 pounds; the Lazareth said to tip the scales at “just” 881 lbs and has a wheelbase of 72 inches. More info at the company’s website.
The Nemesis from the late 1990s would surely have ranked higher if it had reached production, as its specs were scintillating. Its 1500cc V-8 was said to be capable of spinning to a stratospheric 17,000 rpm where it was claimed to produce 290 hp. Most of the engine’s tooling had already been produced for Norton’s 750cc inline-Four Manx project, so engineer Al Melling came up with the idea for the V-8 using a pair of the Four’s cylinder banks. It was to be underpinned by a cast magnesium frame.
Sadly, neither the Manx nor the Nemesis came to fruition, as this was a complicated era in Norton’s history when several independent entities had vested interests in the then-defunct marque. The Nemesis was an adventurous moon shot that unfortunately became stillborn and just a footnote in motorcycle history. The prototype and a test engine currently reside at the National Motorcycle Museum near Birmingham, England. The video below details much of the bike’s history and development, including a run on a dyno that sounds delicious even if it was only run to around 8500 rpm.
Contrasting with the exotic and never-produced Norton is this home-built special that looks far cleaner than a backyard-build has any right to. Not much is known about the CB800, but we can see that its creative owner has fitted a second cylinder bank to a CB400F to create this air-cooled V-8. There doesn’t appear to be many modifications other than a slightly stretched frame, giving it proportions that look almost factory.
The video below sadly does not include any riding footage, but the bike looks and sounds great, aside from a rattling sound at idle from the primary chain. Flawed, perhaps, but I’d still take it for a spin!
The Aurora Hellfire OZ26 is an audacious and over-the-top design, styled by noted designer Tim Cameron. It uses a bespoke flat-plane-crank 2575cc V-8 engine with cylinder banks set at 80 degrees and claimed to produce a retina-squishing 417 horsepower at 9500 rpm. Peak torque is said to be a stunning 235 lb-ft-lb at 7000 rpm.
The Hellfire is the product of mechanical engineer Vincent Messina, an ex-pat Aussie (pictured next to Aurora’s Alison Scoullar) and former racer currently living in Thailand who’d been dreaming of his “ultrabike” for years. Its monocoque design employs a Hossack-style front end and a shaft-driven rear end, yielding a 63.0-inch wheelbase and a claimed dry weight of 594 pounds. More info can be found at Aurora’s website.
The video below shows the Hellfire warming up, and the best part comes after the 2:18 mark when Messina raps the throttle. Who wants to send me to Thailand to ride it?!
Here’s the bike that kicked off this V-8 goose chase, as it’s the most recent motorcycle to be fitted with a screaming V-8. It’s the brainchild of Pat Maloney, a former WSB and GP mechanic from Australia who created his engine by combining a pair of Yamaha R1 cylinder banks at 90 degrees on a billet engine block to come up with a 2.0-liter flat-plane V-8. It’s purported to crank out 334 hp at 12,800 rpm when rated at its countershaft, with peak torque of 157.8 lb-ft found at 9500 rpm.
The V-8 is crammed into a chro-moly trellis frame mated to CNC-machined 7075-aluminum rear elements. It has a 60.6-inch wheelbase and is said to have a wet weight of a reasonable 534 lbs. Brembo, Ohlins, Akrapovic and Motec components complete the package. More info can be found at PGM’s website. It sounds wonderful!
More Aussie audacity is seen in the Drysdale V8, which has roots that stretch back to 1997 when Ian Drysdale built a 750cc V-8 from a pair of Yamaha FZR400 cylinder banks said to produce 161 hp. Then, in a more-is-more attitude, Drysdale built a 1000cc version with FZR600 cylinders, increasing the bore and stroke from 56mm x 38mm to 62mm x 41mm and again mounting them on a sand-cast crankcase. More Yamaha components are found in the highly modified FZR1000 clutch and reworked YZF750 gearbox cluster.
According to our Aussie correspondent, Jeff Ware, who wrote the above feature story, four Drysdale V8s have been purchased for around $80,000. Incredibly, the 750cc version seen in this photo and the below video was stolen from Drysdale’s shop and hasn’t resurfaced. Drysdale had hoped to build two more customer bikes, but we now see that his website is no longer active. The video below gives us an idea of how the flat-plane-crank Drysdale V8 sounds, even if it was revved to only 7000 rpm. We’d love to hear it at its 17,000-rpm redline!
Of all the streetbikes ever created with a clean-sheet V-8, the Morbidelli came closest to production success. However, a frighteningly high price tag ($45k, listed by Guinness in 2001 as the most expensive motorcycle in the world) and Morbidelli’s shaky financial footing resulted in just four V8s (including the prototype) making their way through production by 1998, and the once-proud Morbidelli (with five GP world championships) was eventually shuttered. The V8 was also hampered by odd styling from noted car-design house Pininfarina, particularly the first version seen in 1994 with its disturbing bug-eye headlights and two-tone paint. The styling was soon updated to a more flowing design seen here that was perhaps ahead of its time. It was criticized in 1997, but it looks a little less jarring to today’s eyes.
The heart of the Morbidelli, of course, is its jewel-like 847cc V-8. Its tidy size and exquisite attention to detail pleases eyes to a sublime extent when compared to a Boss Hoss Chevy that was never intended to be looked at without being covered by a hood. The 440-lb Morbidelli is the gentlemanly way to ride a V-8 motorcycle. A mild state of tune delivered a claim of 120 hp at 11,000 rpm being transferred through a shaft drive, said to be enough for a 150-mph top speed.
One of the ultra-rare Morbidelli V8s can be seen at the Barber Vintage Motorsports Museum in Birmingham, Alabama. You can hear it in the video below.
Perhaps the most fully realized of all V-8 motorcycles is the legendary Guzzi V8 Grand Prix racer first seen in 1955. Displacing just 499cc, the 90-degree layout was purported to crank out nearly 80 hp, which was a 10-horse advantage over inline-Fours of the era. Combined with its aerodynamic dustbin fairing, the Guzzi was able to achieve a top speed of 171 mph.
But the 328-lb GP monster was beset by myriad mechanical problems during its three years in competition, amassing only three GP wins and the 1957 Italian Championship. Just five were ever built. More than 60 years later, it sounds as fierce as any motorcycle ever has.