Allen Millyard’s Kawasaki “Z1600” V8 Special…
Recently we’ve been doing a number of features on the mind-blowing creations of Allen Millyard. The mild-mannered tea-drinking English gentleman is renowned for constructing bikes around his own shed-built engines, whose designs beggar belief.
The retired rocket scientist got his bike-building start at the tender age of 11, when he shoehorned an 850cc Morris Mini four-cylinder car engine into a BSA Bantam frame — talk about ambitious! Of course, things have only gotten bigger and madder since then. If you’ve been following BikeBound of late, you’ve seen Millyard’s 5000cc V-twin “Flying Millyard” special, 8000cc Viper V10 bike, and his 2300cc Kawasaki V12, among others.
Today we wanted to take a step back and feature Millyard’s 1600cc Kawasaki V8, his first big four-stroke creation after numerous multi-cylinder two-stroke specials such as his 1000cc Kawasaki widowmakers.
“The Kawasaki Z1600 V8 was my first big bike that I made back in 2000, I made it entirely by hand, with exception of a Myford ML7 model makers lathe. It was quite a complicated build fitting all the extra bits in standard width crankcases but I got there in the end and it ran really nice. I rode the V8 to the Isle of Man TT in 2001.” -Millyard, 2022
Yes, crazily enough, Millyard largely built this Kawasaki V8 with a hacksaw, lathe, some keen eyeballing, and one serious serving of talent and skill. He’s made a great video showing exactly how he did it, featured below. The build likely wouldn’t have been possible if the Zed motor wasn’t so stoutly overengineered.
For those without time to watch the whole video, here are a few highlights. First Millyard cut a Kawasaki Zed crankcase in half and determined how far he could lean back the rear bank of cylinders — this wasn’t done with fancy software modeling or intricate calculations, but with file and eye. He then used a second case, mitered precisely and welded to the first, to create a single V8 crankcase for the engine.
By turning off 5 mm from the width of the standard conrods and slimming down the thrust washers and crank webs, Millyard was able to create enough room to house eight conrods where the standard crank would fit, adding two conrods to each crank pin.
He ended up using slightly smaller (K)Z650 pistons to allow for the offsets between the cylinders — the reason the bike is 1600cc instead of 1800cc. When all was said and done, he had a V8 crankshaft that was exactly the same length as the original, with all of the same bearing locations…who would’ve thought it possible?
Millyard machined eight cylinder liners for the 650 pistons, test-fitted everything, worked out all of the cam and ignition timing, and finally assembled the V8 with new gaskets and seals. He then modified a standard Z1 frame for the engine to fit, had it painted, and assembled the rolling chassis on his kitchen floor!
The battery and electrical components were relocated to make room for the exhaust to exit the rear bank of cylinders. The tank and side panels were both modified to fit the engine, and Millyard cut down two sets of Z1 carbs to work, converting them to the old VM-style in the process.
The bodywork was still out for paint when Millyard took his first ride — he simply filled up the carbs and took it down the street! Unfortunately, there’s only one very short clip of the V8 running and revving, but it sounds properly bestial. You can jump straight to that part of the video below:
Today, the Z1600 V8 is on display at the Barber Motorsports Museum, where we’ve had the pleasure of seeing it in person alongside Millyard’s Z2300 V12. We highly recommend you make the trip if at all possible. It’s an epic place full of historic machines — you won’t be disappointed.
Follow the Builder
Instagram: @allenmillyard
YouTube: @AllenMillyard
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Mr. Millyard is the MacGyver of the motorcycle scene. Give him tools that no one wants and he will make something that ordinary mortals would never even think of. What wife lets her husband wash motorcycle parts in the kitchen sink? And then bake him cookies? It still amazes me how effortlessly he does it all. He is a great inspiration that even in very modest circumstances, great things can be done.
I have spent many hours being bewitched by watching…….no should I
say absorbing Allan’s engineering while
listening very carefully to EVERY word
he utters while performing his motorcycling black magic,
To say he’s my absolute male role model
is a massive understatement by far,
I definitely think myself supremely fortunate to be able to watch his videos
as I am no spring chicken myself, 58yrs
young,
During the mid 80s I was trained to fit,fabricate, and weld by a boilermaker,
here in NZ, And one of my quirks is I REALLY get off on great engineering and design when it comes to things that
usually have two wheels,,,,,oh and of course handlebars,
As far as I’m concerned he is definitely
one of the greats, as far as the motorcycling world goes,
Absolutely bloody fantastic
He’s super clever. But butchering up classic big dollar bikes?? Not sure that’s a good idea. There’s plenty of common bikes sitting that are cheap an plentiful .other than that .I wonder wot the handle like .under power out of corners accelerating. 🤕🥷
Why is this bike in the USA should be in a UK museum so we can see it.
Allen is a pure engineering genius.
My 1st KwikKwak was a KH250 in 1979, travelling from Buxton 2 Macclesfield 6 days a week for 3 yrs.
I then treated myself 2an H1a 500, converting it (siily i know) ti look like a Ducati Darma…i drove it 2 my wedding in 87, then several yrs later gavrle it 2 a good friend of my brothers.
After he stripped it all down, removing the ‘crap’ ide spent £1000s on, he sent me a video and photos of the bike as if it had just left the factory…Thank you Mr Crisp of Buxton for doing a superb job.of it..