2009 Aprilia MXV 450

In a new ‘challenge within a challenge’,
Aprilia is betting on the most revolutionary engine
design of recent times in the tough, competitive world
of motocross. The latest standard bearer for Aprilia’s
off-road design concept is the MXV 450. With its incredibly
compact V twin engine and amazing performance, the
Aprilia MXV 450 is the definitive crosser for riders
determined to win.
As you can see from its essential and unmistakable
styling, the MXV 450 is born to win. Its decisive,
clear-cut lines tell you at a glance that you can
expect light weight and fantastic build quality. Aprilia’s
designers have made full use of the style emblems
that define all Aprilia motorcycles to launch a brand
new look in motocross motorcycles.
Engine
The extraordinary 45.2 engine has already accumulated
titles and victories in enduro and supermotard racing.
Now the same engine has become the heart of the new
MXV 450, the first motocross bike in the world to
be powered by a twin cylinder engine.
In this dedicated motocross version, the 45.2 engine
maintains the unique configuration that has distinguished
it from the start. The V angle remains 77°, and
the cylinders with wet liners remain integrated in
the crankcase. The extremely rational arrangement
of the engine’s accessories has made the Aprilia
V2 engine one of the most compact V twins in the world,
smaller than many singles of similar displacement.
The fundamental innovation of the MXV 450 lies in
the availability of two performance levels, made possible
by two timing settings and designed to satisfy all
possible power delivery needs. The factory default
setting is “Big Bang”. The second “Screamer”
setting offers more regular firing.
The strong point of the “Big Bang” setting
is the exceptional ridability it confers on the bike.
With Big Bang active, the firing gap between the two
cylinders is closed up to produce the excellent performance
so typical of a twin while also guaranteeing easier
control and better traction, two features that riders
are bound to appreciate over slippery surfaces.
The “Screamer” setting requires a minor
modification to the engine and a new mapping. With
Screamer active, the firing gap is the standard gap
for a 77° V twin. “Screamer” delivers
the maximum engine performance suitable for expert
riders.
The sophisticated electronic engine management system
also introduces a number of motocross firsts. The
Dell’Orto fuel injection system with 38 mm throttle
bodies is managed by a programmable ECU that lets
you switch between two different mappings at the touch
of a button on the handlebars.
The "full power" mapping is for use in
conditions of good grip while the "soft"
mapping delivers smoother power for use on more difficult
surfaces. One click is all that it takes to obtain
exactly the performance level you need.
Important opportunities are afforded by the Service
and Programming system. In conjunction with the programming
cable supplied with the bike, dedicated software allows
you to:
- load mapping updates (available from the website)
into the ECU;
- calibrate the “end of line” setting
of the throttle position sensor (TPS);
- within permitted limits, adjust carburation and
timing to align engine characteristics with your
own riding style.
The engine’s amazing light weight is the result
of radical choices in materials. The valves are in
titanium, the crankcase in aluminium silicon alloy,
and all covers are in magnesium. In fact, everything
about the engine is designed for minimum weight in
conjunction with maximum strength and reliability.
All design solutions on the uncompromising MXV 450
have been dictated by the need to achieve the highest
possible level of performance while extending the
bike’s range of use. The under-seat exhaust,
for example, features a brand new path for better
motocross performance with more torque at lower revs.
Valve gear based on a single overhead cam and four
titanium valves per cylinder gives the best possible
compromise between compactness, light weight and performance.
Thanks to its advanced technology the 45.2 engine
is extremely civilised and silent running even in
this motocross version, and complies easily with FIM
rules for noise emissions (94 dB threshold).
The MXV 450 affords beautifully easy access for
maintenance (plugs, oil filter, air filter), and boasts
extended maintenance intervals, far above the average.
The engine has a dry sump lubrication system with
the oil tank integrated inside the crankcase. Elimination
of the external oil tank and its connecting pipes
has led to a further reduction in weight.
The starter motor has been eliminated for the same
reason. Starting is by kick-start only in order to
minimise weight.
The salient specifications of the 45.2 engine
on the new MXV:
- Electronic fuel injection.
- Dry sump lubrication with the oil tank integrated
inside the crankcase. Separate lubrication for gearbox
and engine to keep oil efficient for longer.
- Single overhead cam, titanium valves.
- Single-piece crankshaft.
- Cylinders integrated in crankcase, wet liners.
- Choice of “Big Bang” and “Screamer”
ignition settings.
- “Hard/soft” mappings selectable from
the handlebars.
- Electronic stepper motor idling control.
- Maximum engine speed 12,500 rpm.
Chassis: Lighter Than Ever
The dimensions of the perimeter frame have been optimised
for motocross use, and the entire frame has been developed
to complement the engine. Its design is unique among
motocross frames. A tubular steel trellis is interference
fitted to pressed aluminium side plates to form a
single structure. The engine also forms an integral
part of the chassis, acting as a load-bearing element
and contributing to exceptional overall rigidity.
Particular care has been taken over weight distribution.
Weight has been centralised as far as possible to
improve agility under all conditions. Weight reduction
(one of the most important aspects of any motocross
bike) was central to the design of every part of the
MXV, from disc brake to frame.
The swingarm has been designed for maximum lightness
and elasticity and incorporates hydroformed members.
The rising rate linkage system is damped by a fully
adjustable Sachs racing monoshock with two damping
settings for high and low speed riding.
The Marzocchi upside down fork has 50 mm stanchions
and is also calibrated for motocross. The fork is
fully adjustable, so that you can set up your own
suspension action exactly as you want it.
The fuel tank has been redesigned to keep the bike’s
centre of gravity as near as possible to the physical
centre of the machine. Attention has also been given
to eliminating protruding parts to reduce width and
improve ergonomics.
The centralisation of weight has also influenced
the design of the filter box. The filter is now located
at the front of the bike, leaving the fuel tank more
space to extend back over the rear shock absorber.
The filter box also holds the throttle bodies and
facilitates filter changing.
The ECU and all the components of the electrical
system are also housed securely inside the filter
box.
The exhaust system, under-seat silencer and twin tail
pipes are made entirely from titanium (pipes and silencer).
The minimal electrical system is batteryless, and
fully integrated inside the filter box. Engine and
electrical system therefore form a single block. The
two-tone stepped seat helps the rider hold his position
at all times.
Brakes
The unrivalled technology and performance of the
chassis are supported by a fantastic braking system.
The MXV is equipped with Nissin floating calipers
and super-lightweight wavy discs (270 mm at the front),
for unrivalled braking control in even the most challenging
conditions.
A 240 mm rear disc with single piston Nissin caliper
provides the perfect balance between stopping power
and ease of control.
Aprilia MXV 450 Technical Specifications
- Engine - 77° V twin four stroke. Liquid cooled.
Single overhead cam with rocker operated exhaust
valves, chain timing drive, 4 valve heads, titanium
valves.
- Fuel - Lead-free petrol.
- Bore x stroke - 76 x 49.5 mm.
- Total displacement - 449 cc.
- Compression ratio - 13:1.
- Fuel system - Integrated engine management system
controlling ignition and fuel injection.
- Throttle body: 38 mm.
- Hard and soft mappings selectable from the handlebars.
- Ignition - Electronic digital (batteryless).
- Starting - Kick-start.
- Alternator - 220 W.
- Lubrication - Dry sump. Separate gearbox lubrication.
- Gearbox - 4 speed. Motocross gear ratios: 1st
14/29, 2nd 15/26, 3rd 17/25, 4th 19/24
- Clutch - Multi-plate in oil bath, cable operated.
- Primary drive - Spur gears. Transmission ratio:
23/65.
- Final drive - Chain. Transmission ratio: 14/49.
- Exhaust system - Conforming to FIM standards
for 2009.
- Frame - Cr-Mo steel perimeter frame with aluminium
alloy vertical members.
- Headstock rake angle - 26.2°.
- Lightweight rear frame section.
- Front suspension - 50 mm Marzocchi upside down
fork with adjustments for compression and rebound.
- Rear suspension - Pro-Link with Sachs monoshock,
adjustable in compression and rebound.
- Brakes - Front: 270 mm lightweight stainless
steel floating disc with Nissin floating caliper.
Rear: 240 mm lightweight stainless steel disc with
Nissin floating caliper.
- Wheels - Black anodised aluminium alloy. Front:
1.60 x 21”. Rear: 2.15 x 19".
- Tyres - Front: Dunlop 80/100-21 51M. Rear: Dunlop
110/90-19 62M.
Dimensions
- Overall length: 2,190 mm
- Overall width: 815 mm
- Ground clearance: 1,285 mm
- Seat height: 960 mm
- Wheelbase: 1,499 mm
- Fuel tank Capacity: 7.4 litres.
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