The Kay MV Agusta engine - Great Engines in Bits


An article by Mike Nicks.   Photos by Tim Keeton

The Kay MV under construction




Built to be Thrashed


You expect that replicas of technically straightforward racing bikes such as Manx Nortons, Kawasaki ZXR750s or Matchless G50s will be raced and thrashed mightily. But copies of factory exotica ` Honda sixes, the Moto Guzzi V8, MV triples and fours and the like - you assume will be built for parades. Off-the-shelf parts are not available, component life may be short, and the initial purchase price is usually sky-high. These bikes will lead a sheltered life.
But the Kay family - grandfather David, son Mark, and grandson Mitchell - blow conventional thinking out of the water.. At the 500cc Classic TT on August 31 they will hand two replicas of the twin-cam, 12 valve, MV triple that Giacomo Agostini rode rode in the 1967-72 era to two 25-year-old young-bloods of the modern bike TT, Lee Johnston and Dean Harrison. And they will be told: “Redline ‘em. Take ‘em to 12,500 rpm.” just as Ago did when he won five consecutive Senior TTs on MV triples from 1968-72.
“We are there to win,” says 22-year old Mitch, with all the conviction of a crew chief with years of TT experience. “There’s no point in spending all that time and energy and money just to pose around,” says David, 74. “A lot of people around MVs just want the gold dust of riding them. Having an MV gets you into places that they wouldn’t get to if they had a BSA.”

So you have both youthful idealism and age-tempered realism behind the Kay family’s ambition. And their dreams do not rest just on the 500cc race. For the 350cc Classic TT they’re putting Johnston on a three-cylinder MV of the ’67-’72 period, and Harrison on a four-cylinder bike of the kind that Phil Read and Ago raced in the mid-seventies. Four bikes, three different models, two riders - this is on the scale of a factory team, yet the bikes are manufactured by this family trio in modest workshops behind their house in the West Midlands.
Their audacity is towering - they’re pitting their home-built machines in 151-mile contests against the 37.73-mile Mountain circuit, the greatest bike-breaker of all tracks. But they have recent form - Johnston won last year’s 350cc race on the same bike that he will use this year. He beat Davies Motorsport’s Alan Oversby, on a Honda twin, by 45 seconds.


Mick Duckworth reports on the Kay MV Agusta engine - Great Engines in Bits

The Kay Family’s MV obsession began in 1958 when David first saw the Gallarate machines at the TT. “I was 18, earning 32s 6d a week (!.62) as an apprentice gas fitter in Nottingham. I slept in a bus shelter at the TT. Since then I’ve been to the Island every year except three. It’s where my heroes raced.



In ’58 he witnessed a total MV domination of the TT solo races. John Surtees rode the fours to a Junior Senior double, ad on the 10.92-mile Clypse course an MV twin won the Lightweight 125cc Ultra-Lightweight TT (Carlo Ubbialli). Mike Hailwood, Gary Hocking, Ago and Read.... David saw them all win on MVs.


He didn’t actually own an MV until he was 37, in 1977. “I read that MV was going bust, so I decided that I had to have one,” he says. “I was skint but I paid £3,250 (£60,000 today for a 832cc Monza road bike, depending on condition and provenance”)


Agostini at his best

Ago at Caldwell Park

Mick Duckworth reports on the Kay MV Agusta engine - Great Engines in Bits



Dave Kay in his workshop


The Kays started manufacturing replica parts for MVs in the 1980s, when genuine parts became scarce. They later acquired a compete set of castings for a 1972 500cc four, and many engine drawings from the MV factory. To make their race replicas , they also borrowed original 500cc three-cylinder and four-cylinder bikes from the German collector Willi Marewski and the Brit Dave Bedlington. Making race reps isn’t cheap: there was a £10,000 investment in having engine drawings made, and £80,000 for the equipment.
Their manufacturing techniques are a little old-world, but they’re actually proud of that. “We build the bikes with the same kind of equipment that MV would have used in 1954,” David says. “We don’t use CNC, and our Bridgeport milling machine is 60 years old.
“All our parts are interchangeable with the factory bikes. All right, we use special coatings like everybody else does - diamond coatings on cam buckets, for example. We’ve got a set of drawings for every road bike ever made by MV up to 1980, and we took the time and trouble to convert the Italian material specifications into EN numbers so the material is the same.”


The Kay MV Agusta engine in Bits


They buy in fibre-glass parts, tanks and megaphones, and their frames come from the chassis specialists, Mojo, in Malvern, Worcs.
Major engine components they create themselves.
The conversation about manufacturing techniques leads David into a comprehensive rant about the Classic TT’s technical rules and the kind of bikes that are now appearing in the races.


“It’s getting to be a Wild West show,” he says. “We race the Isle of Man because we think it’s the gold medal of motorcycling for a guy who’s built his bike in a shed in Brownhills. But take the Patons. The cylinders are made out of solid - they’re not cast any more. And they’ve altered the vlave angle so they can use downdraught carburettors.
“You begin to think, ‘what’s the point?‘ You don’t want to disgrace what Agostini and Hailwood did. But the public think, a two-valve Paton, a twin - and an MV can’t beat that? But the Paton is a modern bike made out of solid. If they say there’s no rules, fine - we could build a 130bhp 500cc engine using modern techniques, but it wouldn’t be a true MV.”
David also feels that the four-valve Manx Nortons and Matchless G50s, which Molnar Engineering build, and ultra-short-stroke Manxes, were not made by the factories in the classic period and are not in the spirit of the Classic TT.
It was the TT organiser Paul Phillips who approved the fairly loose Classic TT regs in order to attract a colourful field of bikes to tempt spectators. But while he is critical of the rules, David is equally grateful to Phillips for the help they received in 2014. Phillips has a vast pool of contacts, and can put teams that run into problems in the Island with people who havr a solution. “We got to the Isle of Man, but our rider Dean Harrison had broken both legs and his ribcage at the North West 200,” David says.

“We went to Paul and said, we need a rider. He said try this guy and that one, but not that one because he doesn’t ride classic bikes and he’ll probably wreck it.”
Phillips suggested Lee Johnston, who then delivered that impeccable winning race performance. “Lee was perfect for the bike - his size, weight, and the way he treated it,” Mitch says. “He used his head as well - he wasn’t riding it as though he was on a 200bhp superbike. On a superbike, you can just bang it down through the gears going down to Quarter Bridge. But we don’t have a slipper clutch, so you have to use the clutch and get the revs right. The tyres are smaller on a classic bike, the geometry is completely different to a modern bike, and it’s important to be in the right gear all the time.”
The Kays first raced on the Isle of Man in 2007, when they finished seventh in the 500cc Classic Manx on their replica of the Gilera four on which Bob McIntyre recorded the TT’s first 100mph lap in 1957. In a later race their MV triple recorded a lap of 109.089mph, which beat Ago’s fastest lap of 108.30mph (of course the Mountain circuit has been much improved since then, but there’s another TT bar-room discussion).
Now the Kays, under their Black Eagle Racing banner, will go into battle later this month against the Patons, the Molnar’s multi-valve Manxes and G50, the two-valve Brit singles such as Ian Garbutt’s G50, on which Michael Rutter broke the 500cc Classic TT lap record at 109.102mph last year.
The 24-litre tank capacity means that the singles will be able to power through the four-lap, 151-mile race non-stop, while the multis will have to pit for fuel. Technically, and despite the controversy over rules, it will be probably the most varied and fascinating motorcycle race of 2015.

“We’d rather blow-up halfway up the mountain than come tenth,” David says. “That’s our philosophy.”


The Kay MV Agusta engines revealed - Great Engines in Bits

Looking at he Kay MV Agusta engine - Great Engines in Bits


gifDave and Mitchell Kay in their workshop


David and grandson Mitchell Kay in their workshop


Mick Duckworth reports on the Kay MV Agusta engine - Great Engines in Bits



The Kay MV Agusta engine in Bits





500 cc Triple:

62x54mm bore and stroke
76bhp@12, 500rpm
3x30mm Dell’Orto carburettors
168mph top speed

350cc Triple

56x47.2mm bore and stroke
3x29mm Dell’Orto carburettors
127mph top speed

350cc Four

56x35.4mm bore and stroke
4x29mm Dell’Orto carburettors
130mph top speed







Lee Johnston


Rides 350 and 500cc MV triples
2012 TT Privateers‘ Champion
1st 2012 350cc Classic TT
350cc Classic TT lap record holder: 105.239mph, MV-3 (2014)




Dean Harrison


Rides 350cc four and 500cc triple MVs
1st 2013 Formula Classic TT
1st 2014 Lightweight Supertwins TT



The Kay MV Agusta engines revealed - Great Engines in Bits

Built to be thrashed

An article by Mike Nicks.   Photos by Tim Keeton

The Kay MV Agusta engine - Great Engines in Bits

Here we look at Kay MV Agusta engines - Great Engines in Bits