Four stroke, transverse four
cylinder, DOHC, 2
valves per cylinder
Capacity
593 cc / 36.2 cub. in.
Bore x Stroke
60 X 52.4 mm
Compression Ratio
9.5:1
Cooling System
Air / oil cooled
Ignition
CDI
Starting
Electric
Max Power
43.3 kW / 58 hp @ 9000 rpm /
48.5 kW / 65 hp @
10500 rpm
Max Torque
48.1 Nm / 4.9 kg-m / 35.5 lb-ft. @ 8500 rpm
Transmission
6 Speed
Final Drive
Chain
Frame
Space frame made of chrome-molybdenum steel.
Front Suspension
40mm Italia forks,
adjustable preload
Rear Suspension
Single DeCarbon shock,
adjustable spring preload, 10-way rebound damping
Front Brakes
2x 280mm discs
Rear Brakes
Single 210mm disc
Front Tyre
120/80 V16
Rear Tyre
150/80 V16
Wet-Weight
186 kg / 410.1 lbs
Fuel Consumption
4.8
l/100 km
/ 48.9 mpg
Standing
¼ Mile
12.3 sec / 108.5 km/h
Top Speed
214 km/h / 133 mph
Nestled in a fold of the South Downs is a sleepy
village in the middle of which is an old pub with a thatched roof. The
tranquil picture postcard image is deceptive, however. The fact is the
adjacent square miles contain some of the most testing bits of tarmac for
hustling bikes. A combination of country lanes winding through hills and
valleys, tight tree lined turns, hump backed bridges and for good measure a
new motorway classed road that has been pushed through to take the
sightseers down to Portsmouth. Many expensively produced and lavishly
promoted makes have found their Waterloo upon these roads. A few, very few,
have excelled. On balance the roads have usually defeated them. Until now!
Now the yardstick has been broken the book of comparisons thrown out of the
window. The Bimota's have changed all that.
Even to try a comparison with other machine is
pointless. They are so totally different. You can only try to describe them
and begin to comprehend what they are about. They are simply a different
concept in motorcycling. It is a mark of how far we have gone down the road
of mass marketing for Mr Average that the Bimota's are so unique and so
specifically superior. Specifically, because in overall consumer terms there
are a number of important disadvantages to owning one, not least the price,
and in fact you would be too scared to park it anywhere less secure than a
locked concrete bunker.
A bimota is a very basic motorcycle. There
are no mirrors, no indicators, no pillion seat, no luggage space, and only
enough room for the pilot if he is prepared to stretch and squeeze his body
into the position the machine demands. It is uncompromising, uncomfortable,
anti social, and impractical. It is also the most incredible exhilarating
and beautiful experience on two wheels other than winning the 500 cc World
Championship. Compared to that the bimota is cheap.
Let us go back to the motorcycle as a concept. The Japanese view is that the
machine is a method of transport, a means to an end. This is inevitable
because it was the whole reason for the establishment of their two-wheel
industry. They were not enthusiasts who wanted to go racing and experiment
with engines and chassis design, they were practical businessmen who worked
methodically to provide mobility for a nation and eventually half the world.
If it could not be conveniently made, and profitably sold. It was not worth
considering. To reach the maximum number of customers, a bike is built with
the broadest possible appeal at the cheapest acceptable cost, If that means
cutting corners and accepting lower standards in material and design, that
is all accounted for in the eventual price.
A large part of that price in any case is the cost of promoting and
packaging the product - convincing Mr Average that this really is what he
wants to ride this year. Next year of course he will have to buy something
else because fashion will convince him it is out of date.
Bimota's are not on the mass production merry
go round. True they keep innovating the two new frame kits are a testimony
of that. But even a four-year-old bimota looks advanced and futuristic to
its rivals. Bimota do not see motorcycles as a means of transport, it is not
a means to an end, and it is an end in itself. It is perfection, which is
the goal. Whether it is generally acceptable or affordable does not
particularly bother them, theirs is a statement of fact, not fashion or
frills.
Take the lack of pillion seat as an example.
It is not because of an over large petrol tank or a boy racer seat, it is
because the perfect motorcycle can only be designed to carry one person and
he is already seated as low as possible to keep the centre of gravity down.
If bimota wanted a two seater they would have to redesign the whole chassis.
The design concept is carried through into production without being modified
or compromised by consideration of cost or simplicity. Just look at the
naked bones of the two new bikes reveals the awesome truth. Unlike most bike
frames which are simple cradles or spines, with bits tacked on to carry the
extras, the bimota is a jigsaw puzzle of cross braces, using short tubes in
a triangulated pattern with very little bending as such. It is a principle
much used in aircraft construction because it avoids stress, which is
inherent in long tube runs, which are bent, and then have to be gusseted at
the joints for strength. There are hardly any gussets on a bimota frame. All
the joints in the chrome moly steel tubes are made to take directional
stress end to end along each tube, not only as joints themselves. The tubes
may be compressed but they will not twist nor will they flex. The price of
this rigid construction is complexity. The KB2 frame for the 550 Kawasaki,
for example, has 44 individual tube members from the steering head to the
swing arm pivot. This means pains taking welding on a precise jig - a very
time consuming job for a craftsman only. Despite its web like appearance,
the frame is in fact a cradle. It is just that it cradles the engine from
side to side, not to bottom, keeping the height down whilst giving clearance
underneath for the exhaust pipe. With the tank and seat removed, the rolling
chassis is a virtually mobile workbench, allowing a top end overhaul with
ease - something the Japanese tend to forget about. The only thing that is a
bind to reach on the KB2 is the gearbox sprocket, which is behind the swing
arm pivot. Outrigger forgings house the swing arm bearing directly in line
with the countershaft sprocket to give perfect chain tension through swing
arm movement. Bimota have done away with this on the HB2 frame for the
bigger Honda engine, not so much for maintenance as to keep the overall
width to acceptable levels. The Honda has a massive clutch housing on the
right hand side of the crankcase, which would require too much hardware to
clear. Instead they have gone for a neat alloy casting behind the engine
which replaces frame tube members at the base of the cradle. The intricately
connecting tubing of both frames forms a straight line between steering head
and the swing arm axis, giving maximum rigidity between the two main load
bearing pivots. The engine is just shoe horned into the cradle formed by the
two spars of the backbone. When it is exposed, the Honda motor is revealed
in all it's glory with it's cobby double cam boxes and the threatening open
bell mouths of a bank of four 33mm Mikuni slide carburettors. Just
stationary in the workshop it is a thing of real beauty, a solid structure
of engineering finesse.
The HB2 chassis is obviously higher and wider
to cope with the larger powerhouse beneath and inside it, but other than
that there are a similar number of components. The rear suspension system is
a particular bimota innovation. The Japanese first introduced rising rate
systems on production Motor cross bikes two years ago. Bimota introduced one
that works in 1975. It has been moved around in the chassis quite a bit
because of the variety of frames, but the essential single De Carbon unit
arrangement is retained. It is compressed at both ends, being mounted nearly
upright, with an aluminium rocker arm levered by pushrods mounted on rose
joints above it. The set-up gives an exceptionally high leverage ratio of
8:1 (rear wheel movement to damper rod action) which gives precise control;
but makes it particularly difficult to set the shock correctly for rider
weight and riding style. A small adjustment of the shock translates into a
much bigger alteration in wheel travel. A continuous thread sets preload,
and a click stop knob gives both ten compression and rebound damping
settings. Such great leverage imposes much higher stress on the frame than
conventional twin shocks. Therefore it is doubly important that the chassis
is integrated with the system instead of just having it bolted on the back
for reasons of fashion. The essential difference between Bimota's system and
that used on some large Japanese sportsters is that Bimota's woks better the
j=harder it is pushed. That is the way Bimota's are designed and that is the
way they work. The majority of modern super bikes have a high centre of
gravity, long travel suspension and an excess of power. The combination,
while technically impressive, is potentially highly unstable in
inexperienced hands and often barely manageable even in experienced ones.
The sobering thing about riding a bimota is that it has achieved such a
perfect balance of those forces. You have to learn to ride all over again -
or more to the point, un learn a lot of the instinctive reactions bred by
relatively poor handling machines.
There are other, lighter machines with
less horses that can approach a similar standard, but bimota have harnessed
the giant Japanese power houses and made them work in a motorcycle. It is a
development that has historical validity with a sounder basis than the
sketchy memories of those who just seem to remember that bikes did handle
better in the good old days. They did, but not through any particular
ancient wisdom - the simple fact was that they generally less power and
weight to cope with compared to nowadays.
It is almost indecent to comment on what it
is like riding a bimota, revealing secrets shared by so few. It is harder
still to put the experience into adequate words, so often misused by the
bland description of other mere motorcycles. How do you compare them? By how
much do they steer better? handle better? brake better? There is no suitable
graph on which to plot the relative performance; other than to say that all
comparisons are irrelevant. On a scale from 1 to 10 the Bimota's come in at
around 15. The only reasonable contrast is between the tow models. I rode
the Kawasaki first, some time back, and it felt big and strange. You just
cannot sit on a bimota and cruise around on it. You are forced to conform to
it, squeezing your legs onto the footrests, backside into the seat and
dislocating your shoulder blades to reach the handlebars. This is called
assuming the riding position. Once there, very little else you do seems to
make a lot of difference to the bike. It knows it has got you where it
wants. Now it is in control. You think you have a hold of the throttle, you
think you are using the brakes properly, but the bikes just sat there
chuckling away underneath you because it knows it is not even trying. Like
the GPz550 engine, which is its heart, it thrives on revs. The KB2's motor
has a 600 conversion, although it is not noticeably more powerful, probably
because of the slightly higher overall gearing to make use of the bikes
aerodynamics, in fact if anything it is underpowered, due to the excess of
handling performance. Once you are into the feel of the thing, you find you
can use all of its rpm because the chassis can cope. In comparison, the
Honda feels like a monster. Once your limbs and tendons have been stretched
and contorted by the KB2, they are ready to be further extended by the
additional bulk of the HB2. It feels big; it is big, the weight being
evident in slow speed manoeuvring. After the KB2, it takes a bit of getting
used to. Actually on the road, and at speed, those extra pounds are a help
in some circumstances as they press the bike more firmly on the tarmac. The
KB2 may start to skip on some bumps under acceleration - the HB2 just
thunders over them. Its additional power, of course, is equally dramatic.
Although the conversion will accept standard carbs and airbox, our test bike
had Mikuni racing units and open bell mouths, creating a gorgeous burbling
beneath the tank. They do not like having the throttles yanked open, so
swapping from the fast revving Kawasaki model needs little bit more finesse,
but once under load it surges like a stream train. It is outrageously fast
in a straight line, but the thing that takes longer to appreciate is that it
is extremely rapid through turns. All turns not just long sweeping ones, you
can apply the power smoothly, though tight fiddlely turns where a smaller
bike may have an edge. What bimota have done is made a 900 handle like a
500.
One of the secrets of the new generation
Bimota's is matching all that frame and engine technology to 16 inch wheels,
and making them work. It is something that few, even in racing, have so far
satisfactorily achieved. The 16 inch wheel gives you not only a much lower
bike with a better centre of gravity, but a five inch spread of rubber at
the front and six inches at the back. The V rated Michelin tyres are big, in
fact, their rolling diameter is not a lot less that a conventional 18 inch
wheel, but the overall contact area is so much greater. Compared to them a
normal Superbike wheel looks like it has come off a bicycle. The tread on
the rims gets the power down at all angles, and allows use of the full force
of the three 11 inch Brembo discs. Either stopping or starting the potential
is awesome. The only drawback at the moment is that there are no alternative
tyres, and the shallow treads of the Michelins will not last long with road
use. In the future most big road bikes may have 16-inch rims, but it will be
a long time before they catch up with Bimota's expertise. The reason why
they work is that a smaller diameter requires less leverage on the steering
making the bike more responsive and easier to change direction. The problem
is that the whole chassis has to be designed to handle that potential if it
is not going to become an unstable flying hinge. How far bimota have
integrated that principle is evident when looking at the bare chassis and
engine. Despite the fact that they have got the whole bike as low as
possible on it's small wheels, they have still got the bowels of the engine
- it's heaviest point - close to the axle line. If it were much lower, the
bike would stand up on it's own. A further trick at the steering end is the
offset yokes. The fork yokes are not parallel, but four degrees out of line,
the bottom one being further away from the headstock than the top. This
slightly pushes out the stanchions, compensating for the reducing trail
under heavy braking. Just a little touch, a couple of degrees, but all part
of the precision of perfection. The Bimota's bristle with such niceties,
from fundamental design, to almost trivial detail like flush fitting Allen
headed bolts, and beautifully milled aluminium brackets. Bimota does not cut
corners, instead of running unsightly pipes and plumbing for the brake
hydraulics, they drill the yokes to act as a junction box.
There are no superfluous features on a bimota.
The gulf is now wider than it was a decade ago when Hailwood and Agostini
were locked in a titanic battle for 500 cc honours in racing. Even then the
contrast between the approach of the Honda and MV factory could not have
been more apparent. In order to combat the evidently superbly handling
Italian machine, Honda's solution was an engine with even more power. The
theory was logical enough. If it went fast enough down the straights it
ought to be far enough ahead by the turns. Unfortunately the end result was
a bike that went slower through the corners because it handled so badly. So
it lost all the advantage it gained on the straights. How satisfying for
Hailwood when a supposedly outdated Ducati in the Isle of Man more than ten
years later, he could remind the Honda team that they still had not learnt
the lesson? Perhaps the final comment worth considering is from someone whom
had never seen a bimota before, and knew nothing about them. Mick Whitlock
has never been to a road race and barely ridden a road bike, though he has
spent all of his working life involved with motorcycles. He works in the
equally precise world of trials, building what is generally reckoned to be
the finest chassis kits for one of the most demanding sports. I took the KB2
round to show him, and let him look it over. He did not look at the tank or
the fairing or the paintwork. He studied the engineering, and the quality,
and knew the hours spent. Then I told him the price. "Yes" he said "I can
see why".