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.