Up for Auction: Allen Millyard’s 500-hp Viper V10 Motorcycle!

The 8000cc, 500-bhp Millyard Viper V10 crosses the auction block this month…  

There are custom motorcycles, and then there’s the Millyard Viper V10. Built by legendary British engineer Allen Millyard, this 8000cc V10-powered road-legal motorcycle is one of the most outrageous two-wheeled machines ever constructed.

The Millyard Viper: 8000cc Viper V10 Custom Motorcycle

 

The bike is powered by an 8.0-liter Dodge Viper engine that produces some 500 bhp and 525 lb-ft of torque. Test rider Bruce Dunn has ridden the bike over 207 mph, and it carried Allen Millyard and Henry Cole to a Guinness-certified tandem speed record. It has done real road miles, too, touring the Isle of Man and racking up nearly 10,000 miles around England, becoming one of the most famous homebuilt motorcycles on the planet. And now, for the first time, it’s going up for auction.

H&H Classics will offer the 2009 Millyard Viper V10 at its National Motorcycle Museum sale in Solihull, West Midlands, on July 22, 2026. The estimate is £100,000 to £150,000, and the bike is being offered directly from Allen Millyard’s personal collection. You can see the auction listing here.

For most builders, a V10-powered motorcycle would be the fever dream that never leaves the sketchbook. For Millyard, it became a fully functioning, road-legal machine — and one that has covered more than 9000 miles.

One of Millyard’s Most Significant Creations

Allen Millyard is a motorcycling treasure: a soft-spoken, tea-drinking mechanical genius whose creations seem to emerge from an alternate universe where factory engineers were given unlimited imagination, unlimited patience, and no corporate oversight. Over the decades, Millyard has built an extraordinary roster of multi-cylinder motorcycle specials: five-cylinder Kawasaki two-strokes, six-cylinder Zeds, a Kawasaki V8, the mighty V12 Zed, the 5000cc “Flying Millyard,” and many more. Several of his creations have found their way into the Barber Vintage Motorsports Museum in Alabama, a testament to their historical and engineering significance.

2300cc Zed: Kawasaki Z2300 V12 Motorcycle

But the Viper V10 sits in a class of its own. H&H says Millyard himself has described the Viper as one of the most significant and recognizable machines in his personal collection. It’s not hard to see why. Even among a lifetime of improbable builds, this machine remains staggering.

Beating the Tomahawk at Its Own Game

The origin story has become part of motorcycle folklore. In the early 2000s, Dodge unveiled the Tomahawk, a four-wheeled concept powered by an 8.3-liter Viper V10. It looked like something from a sci-fi film, and Dodge made outlandish performance claims for it, but it was more rideable sculpture than genuine motorcycle. It was not street legal, independent high-speed testing never materialized, and the few examples sold were essentially collector pieces.

Millyard’s son Stephen saw the Tomahawk and told his father he could do better. Soon afterward, Stephen found a Dodge Viper engine on eBay. Allen bid on it, won it, and the project was born.

Where the Tomahawk was a corporate publicity exercise, Millyard’s machine would be a true motorcycle: two wheels, road legal, and capable of the speeds its engine suggested. The result was not merely a rebuttal to the Tomahawk, but a machine that arguably made good on the fantasy Dodge had advertised.

The 8000cc Heart

The Millyard Viper V10 is powered by an 8.0-liter, 20-valve Dodge Viper GTS engine. The powerplant develops around 500 bhp and 525 lb-ft of torque — figures that make sense in a car, but are nearly unthinkable in the context of a road-going motorcycle.

The engine is not simply stuffed into a conventional frame. Instead, the V10 itself acts as the central stressed member of the motorcycle. A tubular steel front subframe bolts to the engine, while an alloy rear subframe attaches behind it. The single-sided swingarm is mounted to the gearbox.

Millyard’s usual workmanship is everywhere. The handmade exhaust headers were ceramic coated, the silencers were modeled after Suzuki TL1000S cans to suit the bike’s street-cruiser aesthetic, and the machine was engineered to look cohesive rather than cobbled together. That has always been one of Millyard’s trademarks. Even when the concept is absurd, the execution is careful, measured, and deceptively factory-like.

Forks from JCB Rams

Naturally, no off-the-shelf motorcycle suspension was going to be suitable for a V10-powered machine of this size. For the front end, Millyard fabricated custom forks using 75mm JCB hydraulic ram stanchions, converted Vauxhall Carlton damper rods, and Hagon springs. Out back, the bike uses two recalibrated Yamaha R1 shock absorbers.

This is classic Millyard: practical, inventive, and slightly unbelievable. Where others would have waited for expensive bespoke components, he adapted existing heavy-duty parts into a system that worked. The result is a motorcycle that looks like a muscle car engine has grown wheels, controls, suspension, and a number plate — because in a very real sense, that is exactly what happened.

Road Legal and Over 200 MPH

The Viper V10 was completed in 2009 and passed the Motorcycle Single Vehicle Approval test before being registered for road use. Its original registration was RX09 LVH, though it later acquired the far more appropriate plate V10 OTT after winning the “Most OTT” award at Salon Privé. And unlike many headline-grabbing specials, the Viper was not built merely to sit on a stand.

In August 2009, shortly after the bike was road registered, MCN Chief Road Test Rider Bruce Dunn rode the Viper V10 at Bruntingthorpe Proving Ground. Using a taller rear sprocket and without running full throttle, he was clocked at 207.101 mph. That number is all the more impressive when you consider this is not a streamlined land-speed machine. It’s an upright, naked, road-legal motorcycle powered by a massive V10 engine, with the rider hanging on in the wind blast.

Millyard himself has also ridden the bike at more than 200 mph, and the machine has covered more than 9,000 miles in total, including trips to Guernsey, the Isle of Wight, and the Isle of Man, where Millyard rode it around the TT course.

The Two-Up Record

In May 2023, the Viper V10 added another chapter to its story when Allen Millyard and TV presenter Henry Cole set out to break the Guinness World Record for fastest speed achieved by a tandem motorcycle. With Millyard riding and Cole on the pillion, the pair were officially timed at 183.50 mph at Elvington Airfield in North Yorkshire. Guinness certified the run, and the pair beat the previous record, which had stood since 2011.

That record has since been surpassed, but the 183.50-mph run remains one of the great moments in the Viper’s history. There are faster motorcycles. And there are faster two-up motorcycles now, too. But few people would look at a homebuilt, 8.0-liter, V10-powered motorcycle and decide the logical next step was to take a passenger past 180 mph. That’s the kind of madness that makes Millyard’s Viper a legend as much as a machine.

The Auction

H&H Classics will offer the Millyard Viper V10 at the National Motorcycle Museum in Solihull on July 22, 2026. The bike is being sold directly from Allen Millyard’s personal collection and is accompanied by a history file, V5C registration document, and two interchangeable seats: a lower-slung, more supportive solo seat and a traditional-looking dual seat. As stated above, the estimate is £100,000–£150,000.

For a one-off, road-legal, 500-bhp motorcycle built by one of the greatest custom engineers of the modern era, that estimate may prove conservative. This is not merely a curiosity. It is a landmark machine — one with genuine road miles, proven performance, a world-record chapter, and a level of craftsmanship that reflects Millyard’s singular approach to engineering.

Auction Details

Model: 2009 Millyard Viper V10
Builder: Allen Millyard
Engine: 8.0-liter Dodge Viper V10
Claimed Output: 500 bhp / 525 lb-ft
Registration: V10 OTT
Auction House: H&H Classics
Sale: National Motorcycle Museum, Solihull
Auction Date: July 22, 2026
Estimate: £100,000–£150,000
Mileage: 9000+ miles, according to H&H
Road Status: Fully road legal
Included: History file, V5C, two interchangeable seats

A One-Off, Built by a One-Off

Motorcycling has always had room for eccentrics, dreamers, shed engineers, and stubborn geniuses. But even in that proud tradition, Allen Millyard stands apart. The Viper V10 is not just a big engine in a motorcycle. It is a machine that proved a ridiculous idea could be made coherent, road legal, and genuinely fast. It was built not by a factory or race team, but by one man with a home workshop, deep engineering knowledge, and a refusal to accept that something was impossible simply because no one else had done it.

The new owner will not merely be buying a motorcycle. They will be buying an artifact of modern motorcycling — a machine that distills everything people love about Allen Millyard’s work: imagination, mechanical bravery, and an almost supernatural ability to make the impossible look neatly engineered. A one-off built by a one-off, indeed.

Follow the Builder

Instagram: @allenmillyard
YouTube: @AllenMillyard

Auction Listing

H&H Classics: 2009 Millyard Viper V10
Auction Photos: Gun Hill Studios / H&H Classics

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