MV Agusta F4 750S Serie Oro

There has surely never before been a motorcycle whose apparently ordinary technical specification liquid-cooled, 750cc dohc 16-valve inline four hid so much innovation. Almost every significant component of the F4 has been freshly created by Cagiva, mostly at the CRC (Cagiva Research Centre) design studio in San Marino, headed by Massimo Tamburini and his right-hand man Massimo Parenti.

Only the engine was developed at Cagiva's Varese base; and the powerplant, too, is unconventional although less so than originally planned. The 749cc unit, very oversquare at 73.8 x 43.8mm, features the radial four-valves-per-cylinder layout drawn up more than ten years ago, in collaboration with engineers from Ferrari.

Early progress was slow, but accelerated in 1994, when Claudio Castiglioni took the painful decision to scrap Cagiva's 500cc GP team (after John Kocinski had just finished third in the world championship) in order to concentrate on the F4 project. The GP engineers were put to work on the four-stroke motor and completely redesigned it, abandoning the original design of offset cylinders (two forward and two back, reducing width) and forward-facing intake system.

The early prototype's radial valves, operated directly (via bucket-and-shim adjusters) by the specially shaped camshafts, were retained, as their performance benefit was found to justify the additional complexity and cost. With radial valves the gas flow shape is much better power is good and the torque curve is very favourable, says Andrea Goggi, the youthful former Cagiva 500cc racing engineer who headed the development team. The original motor's removable cassette gearbox was also kept; alternative ratios will be produced for racing.

Following the F4's unveiling 18 months ago, the delay in starting production was caused largely by the need to make sure that every component supplier was able to deliver reliably at the quality required (some parts were rejected several times). But the extra year has also been useful for further engine testing. Besides performance, our main goal has been reliability, says Goggi. That is absolutely essential.

The Weber-Marelli fuel-injection system has also benefited from continued development. We have spent a lot of time with the fuel-injection, making sure the transition from closed to open throttle is very smooth, Goggi says. Tamburini himself designed the 4-2-1-2-4 pipe exhaust system, which ends in that striking under-seat quartet of silencers, after dismantling and rebuilding the exhaust of Claudio Castiglioni's Ferrari F40 to check some ideas.

Tamburini's involvement ensured that engine details such as the clutch cover were specially designed, in conjunction with the fairing, for minimum width. The maestro's frame is notable not just for its combination of chrome-molybdenum steel tubes and cast magnesium (aluminium on the F4S) swing-arm pivot sections, but also for the way that the front and rear sections can be unbolted for rapid access to the motor a feature that Bimota co-founder Tamburini introduced on that firm's SB2 in 1977. The rear subframe is small-diameter aluminium tube.

If any one component sums-up the Serie Oro it's perhaps the swing-arm. The subject of a university thesis, it was designed using computerised stress analysis, looks totally gorgeous, and when cast in magnesium weighs just 3kg. The F4S's aluminium version is 50 per cent heavier.

Steering angle is a non-adjustable 24 degrees, with 98.5mm of trail (steering head inserts to give adjustable geometry will be available as racing kit parts). The 49mm upside-down Showa forks also feature quick-release clamps for the large-diameter tubular wheel spindle. Like almost every major chassis component, they were specially developed in conjunction with CRC.

So too were Nissin's six-piston front brake calipers and their master cylinder, which incorporate technology used in Cagiva's 500cc GP bike. The 310mm floating front discs are held by a 17-inch, five-spoke magnesium front wheel (aluminium for the F4S); the four-piston rear caliper bites a tiny, lightweight 210mm disc.

At Tamburini's request both Pirelli, who provided the new Dragon Evos for the launch bikes, and Michelin have developed special 120/65-section front tyres that are claimed to give the light handling of a conventional 120/60 with the more neutral feel of a 120/70. Rear rubber in both cases is a 190/50 radial on a six-inch rim.

The bodywork combines style and function to an unprecedented degree, particularly on the Serie Oro, which uses carbon-fibre where the F4S will be plastic. Both models share the quick-release fasteners, integrated mirrors/front indicators, practical and stylish instrument panel, adjustable hand and foot controls, and the neat and compact stacked polyellipsoidal twin headlight design. Given the amount of work that the 35-strong CRC team put into developing and producing even the tiniest components, it's no wonder the F4 took more than ten years to reach production.

MV Agusta: Rebirth of a Legend Monza is not the most interesting circuit in Italy, but as the venue for the relaunch of MV Agusta it was the obvious choice. The old circuit to the north of Milan was the scene of many victories for the old MV firm, which was based at nearby Gallarate and dominated grand prix racing for many years. In total the firm won 270 grands prix and 75 world championships, including no fewer than 17 consecutive 500cc titles between 1958 and '74.

Count Domenico Agusta, the son of a Sicilian aviation pioneer, founded Moto Verghera Agusta by building small-capacity two-stroke bikes in 1945, and was soon successful. Domenico loved racing, and his riders including Britain's Cecil Sandford and Italian ace Carlo Ubbiali won world championships in the 125 and 250cc classes in the 1950s.

It was the 500cc Gallarate fire engines for which MV became best known, especially during that period of domination after the rival Italian factories had quit racing in 1957. John Surtees (four titles), Gary Hocking, Mike Hailwood (also four), Giacomo Agostini (seven, plus six in the 350cc class) and finally Phil Read (two) maintained an unprecedented period of 500cc dominance.

But in 1975 Read's four-stroke MV could no longer hold off the two-strokes, and ironically it was Agostini who took the title for Yamaha. By this time Count Domenico, the firm's driving force, had died of a heart attack. MV had also built exotic four-cylinder roadsters such as the 750S and fully-faired 750S America in the late '70s, but they were too expensive to produce, and the firm ceased trading in 1980.

The seeds of the revival were sown when Cagiva boss Claudio Castiglioni bought the MV name from the Agusta family in 1992, and decided to use it for the 750cc superbike that was originally known as the Cagiva F4. Massimo Tamburini had originally designed the four with a fairing nose similar to Cagiva's 500cc grand prix bike, and the F4 was completely revised before reaching its present form.

Following MV's return with the F4 Serie Oro, other models will be added to form an exclusive range. The F4S, due in July at approximately half the Serie Oro's price (under £13,000 compared to about £24,000 but there's a year-long waiting list), will be built at Cagiva's new factory in Cassinetta, using engines assembled at the old Schiranna plant on the opposite side of Lake Varese. About 1500 bikes will be built this year, the figure increasing gradually in the future.

At this September's Milan Show MV is likely to unveil a naked version of the F4, powered by a detuned 750cc engine in an identical frame, which will be produced next year, as will a dual-seat Biposto model. Further into the future, there will also be a sports-touring variant, plus a series of models with larger engines. An 846cc F4 prototype produced 140bhp several years ago.

MV chose to produce the F4 with a 750cc engine first so the bike could form the basis of a World Superbike racer. The marque's competition return is likely to move closer next year with the introduction of a tuned Sport Production version of the F4. Castiglioni refuses to comment on his racing plans, but it is possible that MV will be back on the grid in 2001.

For a moment I was in trouble. This was only my fourth ever lap of the Monza circuit, north of Milan, and as the MV Agusta F4 howled towards the tight chicane after the famous Curve Grande right-hander, I was confident that I had my braking marker fixed in my mind.

But that marker did not allow for the fact that on this lap, for the first time, I'd found the courage to hold the 750cc four flat-out through the ultra-fast Curve Grande. The MV's front brake slowed the bike with its normal ferocity but as I approached the chicane I suddenly realised I was travelling faster than before. With eyes bulging behind my visor and no more room to shed speed, all I could do was throw the F4 into the left-hand turn regardless...

I needn't have worried. Seconds later I was through the chicane and accelerating hard down the next straight with my head behind the bubble, the F4 having sliced through the left-right combination with such ease that the incident was already history and my braking point had been proved right after all. Such is the agility and the cornering power of the F4 that its limits had still not been thoroughly examined.

Unfortunately I never did get to know either Monza or the F4 Serie Oro quite as well as I'd have liked. After a few more laps on that bike and another F4, rain arrived to end my testing of the 16-valve 750. But that moment's panic at the chicane had merely helped confirm what the previous few laps had suggested: reborn MV Agusta's debut model, more than ten years in development, is a remarkable bike with the speed and, especially, the handling to match its sensational looks.

Few bikes can have been as eagerly awaited as the F4, about which so much has been said and written since its unveiling in Milan in September 1997. All these months later, it's still every bit as jaw-droppingly beautiful. Even in the gloom of an overcast April day at Monza the traditional MV home circuit, chosen as the launch venue by Cagiva boss Claudio Castiglioni for unashamedly nostalgic reasons the F4 manages to look radiant from every angle.

More even than its skilfully sculpted shapes and forms, it's the F4's incredible attention to detail that captures the eye. From the tiny polyellipsoidal twin headlights placed one above the other in the nose of its fairing, all the way to the four cigar-shaped silencers jutting from beneath its equally original and beautifully formed tailpiece, the MV has been designed and put together with consummate skill and an absolute refusal to take the easy option of using bought-in components.

That impression is maintained when you climb aboard and ease into the seat, which is thinly padded and, at 790mm, low enough for most riders to get both feet on the ground. The F4 Serie Oro is light and compact, weighing 184kg dry and with a 1398mm wheelbase (making it 7kg heavier and 3mm longer than Yamaha's R1), but it's reasonably roomy even if you're tall, and the footrests' position is adjustable.

Ahead is a unique view dominated by the stylishly asymmetrical instrument panel, in which a digital speedometer sits to the left of a large, yellow-faced tachometer calibrated to 17,000rpm. Huge red-topped fork legs (at 49mm in diameter the Showas are wider than those of any other production bike), complete with preload and damping adjusters, protrude through the top yoke.

The aluminium yoke carries a small oval badge with the number 004/300, signifying that this bike is one of the first few Serie Oro, or Gold Series, F4s of which a total of just 300 will be built. An adjustable …hlins steering damper is mounted transversely and fixed at both ends, in a new layout patented by CRC. Even the front brake and clutch master cylinders are freshly designed, ultra-compact and the subject of three separate patents.

Hit the starter button, blip the throttle, and you're rewarded with a deliciously crisp and tuneful exhaust note from the radial 16-valve motor. As I headed up the Monza pit lane with the F4's low-rev warble turning into a full-blown howl, I assumed the bike was fitted with a factory tuning-option pipe, but MV has somehow managed to homologate this system for street use. Well, this is Italy...

Maximum output of the 749cc motor is a claimed 126bhp at 12,500rpm, which is actually 7bhp less than Suzuki's GSX-R750 (to name one current rival), and it's clear that there's no way the F4 could be competitive with open-class sportsters such as the R1 in a straight line, either on top-end power or midrange grunt. Peak torque of 54ft.lb is produced at a highish 10,500rpm, but by 750cc standards the Italian bike has a linear power delivery. It pulls cleanly from low revs and pretty hard from below 8000rpm, which was about as low as the needle dropped through Monza's chicanes, before really letting rip at the top end.

The motor was impressively smooth, too, especially the first of the bikes that I rode, which was a well-thrashed development F4 (complete with un-anodised magnesium swing-arm), in contrast to the trio of immaculate machines that had been run-in for the launch. While the newer bike I rode had a slight high-frequency buzz typical of a Japanese four, the first was remarkably smooth all the way past the red-light warning at 12,600rpm, till it hit the limiter at 13,300.

MV claims a top speed of 175mph, and says the F4 has recorded a genuine 178mph on a slight slope during testing at the Nardo circuit in southern Italy. I must have reached over 150mph (no time to look) on Monza's long start-finish straight, before hitting the anchors for the first chicane. Equally importantly, the six-speed gearbox on both bikes was supremely slick, and the F4's fuel-injection system gave a notably smooth and controllable response when the throttle was wound open in mid-corner.

That helped the MV get out of the bends fast, but it was the chassis that was the star of the show. The frame of tubular steel and cast magnesium is immensely rigid, as is the hunky magnesium swing-arm. They combined with the high quality suspension, light weight and sharp geometry to make the F4 manoeuvrable, precise and wonderfully stable. Most fun was the famous Parabolica, a fast, never-ending right-hander where you could just hurl the bike on its side, plant your knee on the ground and whiz round, getting on the gas harder and harder as the curve spilled out onto the start-finish straight.

Again the well-used development bike felt slightly the sweeter of the two F4s that I rode, which Tamburini put down to its suspension being better run-in. The Sachs shock worked well, but I would have liked to try firming up the rear end of both bikes to suit my 14-stone weight. Two much smaller and lighter testers who rode the F4 immediately before me pronounced it the best-handling 750cc roadster they'd ridden, so it was hardly surprising that the bike felt a bit soft for me.

Both front and rear suspension units are multi-adjustable, and the rear end can be altered not only for ride height, but also to give a choice of rising-rate by using alternative pivot points for the rocker-arm. Given more track time and a few stops for adjustment, I'm sure the already fine-handling F4 could have been given even quicker steering with no notable loss of stability. But with a queue of eager journalists awaiting their turn in the pits, there's no way I was going to risk coming in before I had to...

There was definitely no need for fine-tuning of the braking system, as the pair of specially developed six-piston Nissin calipers bit the 310mm discs enough controllable force to stress even those drainpipe-like upside-down Showas. Pirelli's new 120/65-section Dragon Evo Corsa front tyre, produced in collaboration with CRC, gave heaps of grip and a very neutral steering feel, too, although its influence on the overall handling package was hard to judge.

Similarly, we won't know just how competitive the F4 really is until it's pitched head-to-head against some serious opposition. For all its stunning looks and innovative technology, cynics will argue (and with some logic) that the Serie Oro is no lighter or more powerful than a GSX-R750 costing less than a third of this bike's £24,000 price, and that for most riders the MV's classy chassis won't make it significantly faster than the Japanese bike.

But to assess the F4 Serie Oro in such terms is to miss the point regarding a bike that is one of the most stylish and immaculately detailed vehicles ever built, as well as one that will for ever be remembered as the machine with which one of the world's greatest motorcycle marques made its return. For the F4 to be this fast, this agile, this special, this good right from the word go is an achievement to match any in the long and glorious history of MV Agusta.

Source insidebikes.com