Most of us, when faced with a spare engine and a bit of time, might think about a winter rebuild or perhaps a café racer project. Allen Millyard, on the other hand, looks at an 8.0-litre Dodge Viper V10 sportscar and thinks: that’ll make a decent motorbike.
And now, in what feels a bit like the mechanical equivalent of Sotheby’s auctioning off Picasso’s sketchbook, several of Millyard’s creations are heading to the block at H&H Classics this July at the National Motorcycle Museum.
The headline act? It could only be the Millyard Viper V10.
Let’s just pause on the numbers for a moment.
- Eight litres.
- Ten cylinders.
- Around 500bhp and 525lb-ft of torque.
- A machine that has been clocked at 207mph.
That’s not motorcycle territory. That’s supercar territory. Yet somehow, through a mix of engineering brilliance, lateral thinking and what can only be described as cheerful insanity, Millyard made it road legal.
And not “road legal” in the way some wild customs are wheeled out once a year for a sunny Sunday. This thing has done over 9,000 miles, including trips to the Isle of Man, Guernsey and the Isle of Wight. That tells you everything about Allen’s approach: these aren’t static sculptures. They’re meant to be ridden.
Built over five painstaking years from a Dodge Viper GTS engine, the V10 became an instant legend when MCN’s Bruce Dunn rode it to over 207mph at Bruntingthorpe. Dunn later compared the experience to being “on top of the Atlas rocket.” Brave lad. MCN video here.

Then there’s the Fastest Tandem Motorcycle World Record. Because apparently riding it solo wasn’t ridiculous enough, Millyard convinced Henry Cole to climb on the back and together they hit 183.5mph at Elvington in 2023. Friendship comes in many forms.
What makes the Viper so fascinating isn’t just the absurdity of it all, but the finish. Like all Millyard builds, it looks right. Not cobbled together. Not cartoonish. It has that uncanny high quality construction, as though some alternate-universe Dodge motorcycle division might have built it.
It’s estimated at £100,000–£150,000. Which, for a world-record-holding, one-off piece of engineering history, suddenly doesn’t seem all that wild.
But it’s not coming alone…
Millyard’s Kawasaki S1 550 Special

Also crossing the block is Millyard’s Kawasaki S1 550 Special, a four-cylinder two-stroke derived from the humble S1 triple. This is classic Millyard territory — taking something familiar and quietly, surgically turning it into something utterly bonkers.
From the outside, it almost looks standard. Until you realise it has an extra cylinder and a completely bespoke crankshaft.
Estimate? £24,000–£26,000.
Honda-Kawasaki “SS250”

Then there’s the wonderfully mischievous Honda-Kawasaki “SS250”, essentially a tiny Honda SS50 stuffed with a 250cc Kawasaki motocross engine. Think of it as the world’s angriest fizzy.
Originally a 3bhp learner bike, Millyard’s version now makes nearly 29bhp at the rear wheel, which in something this small must feel absolutely hilarious. Formerly ridden by Carl Fogarty, no less. Estimate: £14,000–£16,000.
The genius of Millyard
What makes Allen Millyard special is that he isn’t building customs for shock value. There’s engineering integrity in everything he does. He’s one of those rare people who sees machinery not as fixed, but fluid — something that can be reshaped, improved, reimagined.
He’s the sort of man who adds cylinders to engines as casually as the rest of us fit heated grips.
And crucially, he builds with humour. There’s wit in the Viper V10. Wit in the Flying Millyard. Wit in all those Kawasaki hybrids. They make you laugh first, then stare, then slowly appreciate the genius.
For collectors, this sale is a big moment. Millyard has held onto many of these bikes for years, and the Viper especially feels like one of those machines that belongs in a museum —or a very brave private collection.






























