2009 Yamaha XJ6 Diversion

An ideal balance of controllability, performance and value.

The demand for stylish and affordable middleweight motorcycles in Europe is growing, and for the 2009 model year Yamaha will introduce the new XJ6 Diversion.

Featuring a lightweight half cowl, this stylish new 600 has been designed to offer riders of all ages and experience levels the opportunity to own a stylish, sleek and fun-to-ride machine which has been created to deliver an ideal balance of controllability, performance and value.

Powered by an inline 4-cylinder engine which has been tuned to deliver a linear flow of strong yet easy-to-control torque, the XJ6 Diversion is one of the most flexible, rider-friendly and accomplished designs in the 600 class. Around the city, on twisty mountain roads or on the highway, this engine delivers the performance and character that today’s middleweight rider demands.

Manufactured from high-tensile steel tubing, the all-new lightweight diamond-type frame gives the XJ6 Diversion a timeless and charismatic new look. Featuring dimensions and geometry that have been selected by Yamaha’s engineers to ensure easy handling and optimum controllability over a wide range of speeds, the XJ6 Diversion chassis combines style with substance. A low seat height allows riders to get their feet on the ground with ease, and with ABS available as an option, the XJ6 Diversion is sure to appeal to a wide range of customers throughout Europe.

Possessing a style, character and quality that makes it stand out in a crowd, the new XJ6 Diversion brings a new level of excitement to the middleweight category.

Engine

Newly-developed 600cc liquid-cooled 4-stroke inline 4-cylinder engine

The XJ6 Diversion is driven by a newly developed 600cc liquid-cooled 4-stroke inline 4-cylinder engine which has been specifically designed to produce brisk performance together with an easy, predictable and linear power band.

This new design employs the basic architecture of the highly successful FZ6 engine – and shares its bore x stroke dimensions. However, although the engine’s external appearance is similar to the FZ6, the XJ6 Diversion powerplant is equipped with a wide range of new model-specific features.

Virtually every major feature on the XJ6 Diversion engine is new, and the cylinder head, crankcase, intake/exhaust systems, clutch and shifter have been developed specifically for this new middleweight. By optimizing the new engine’s entire gas flow – from the air/fuel mixture right through to the combustion and exhaust processes – Yamaha’s team of engineers have successfully created a highly responsive and characterful new engine with a linear and rider-friendly torque character.

Easy-to-handle torque output

Featuring bore x stroke dimensions of 65.5 mm x 44.5 mm, together with a high compression ratio of 12.2:1, this strong and responsive new inline-4 cylinder engine produces maximum horsepower 57.0 kW (78 PS) at 10,000 rpm, with maximum torque 59.7 Nm (6.1 kg-m) at 8,500 rpm.

During the engine development process, a major goal was to create a rider-friendly torque output, and many of the design features seen on the new engine were introduced in order to achieve brisk yet smooth power characteristics that would be appreciated by new and experienced riders alike.

The new engine internals – as well as the intake and exhaust systems – have been tuned to deliver plenty of easy-to-handle torque in the low to mid rpm range. These new design features have been successful in achieving the aims of the engineers, and the new XJ6 Diversion delivers a relatively linear power and torque feel which offers a very special ride quality, together with strong performance in the most frequently-used rpm range.

Newly-designed cylinder head

In order to enhance low to mid-range torque, and also ensure good throttle response combined with an easy-to-use character, the XJ6 Diversion is equipped with a newly-designed cylinder head. The inlet and exhaust valve diameters on the 4-valve head design are the same as those on the FZ6 for optimal gas flow efficiency, and for an increased torque feel in the low to mid engine speed range, the new XJ6 Diversion features reshaped inlet ports.

In addition to the reshaped inlet ports, the new head is fitted with 32 mm throttle bodies, and these, combined with the slimmer ports, help to ensure optimized intake air volume.

New camshaft profiles

Another significant model-specific feature that has been developed for the new XJ6 Diversion is the use of redesigned camshafts which have been developed to complement the advantages gained by the revised inlet port shape.

The new camshaft designs give a revised valve lift of 6.6 mm together with a narrow overlap of 34 degrees where the four intake and exhaust valves are all open. Together with the new engine’s high compression ratio, this specification makes for high torque in the low to mid-rpm ranges, and also ensures excellent throttle controllability in the frequently used 4,000-5,000 rpm band.

Another advantage of the narrow overlap is that it minimizes the blow-by of unburnt gases, which helps to ensure increased combustion efficiency, and it also contributes to high levels of fuel efficiency and enhances the easy-to-handle nature of the new 600cc engine.

One-piece cylinder and upper crankcase

The XJ6 Diversion engine benefits from the use of a newly designed one-piece cylinder and upper crankcase assembly, and this efficient design gives an optimum balance of rigidity. In order to ensure consistently high levels of heat dissipation, the 65.5 mm diameter bores are treated with a ceramic-composite plating process, using Yamaha’s unique high-speed plating technology.

Forged aluminium pistons

The new XJ6 Diversion engine is equipped with forged pistons which offer a number of advantages over cast pistons. During the forging process the aluminium alloy is heated and the piston is formed under pressure without actually melting the aluminium. Unlike casting, in which the molten aluminium is poured into a mould, the forging process allows the aluminium to retain more of the original strength of the metallurgic matrix.

Consequently, the forged pistons used on the XJ6 Diversion can be made lighter than the equivalent cast piston, and this weight reduction helps to minimize vibration, and also reduces reciprocating weight to give instantaneous throttle response.

Optimized fuel injection mapping

For excellent response together with good environmental performance, the XJ6 Diversion is equipped with four-hole two-direction injectors with a high dynamic range, while a 32-bit ECU delivers precise injection control. The actual fuel injection hardware is similar in appearance to the system used on the FZ6, but important changes have been introduced. Modifications have been made to the sensor and also to the software in order to enhance the XJ6 Diversion’s highly responsive, rider-friendly character, and to ensure strong overall performance.

The revised fuel injection mapping has been designed to match the new engine specifications and optimize the linear power characteristics and enhance torque levels in the low to mid range.

4-2-1 exhaust with midship muffler

The newly designed 4-2-1 type exhaust system features four exhaust pipes which flow neatly into a single midship muffler which sits beneath the centre of the new tubular steel chassis. The three-stage expansion muffler emits an attractive exhaust note, and is equipped with a three-way catalytic converter for good environmental performance. The system is also fitted with an O2 sensor which monitors exhaust gases, and transmits this data to the ECU, which instantaneously adjusts the fuel/air mix to the optimum level to ensure effective catalyzer operation.

New clutch and shifter design

The XJ6 Diversion is designed to be a modern, practical and fun middleweight which is attractive to new and experienced riders, and in order to make it even more easy to use on city streets, a completely new clutch and shifter are fitted.

The new clutch has an inner-push type release mechanism, and this system is renowned for its ease of use. With its smooth and light operation, the new inner-push clutch offers good feel when it is semi-engaged, giving the XJ6 Diversion rider a good feeling of control in typical urban stop-start riding situations.

As well as an all-new clutch design, this lively new middleweight benefits from the fitment of a completely new shift system. Combined with the new clutch, the redesigned shift mechanism delivers smooth and easy shifting in all situations, making this attractive new motorcycle an ideal choice for those riders looking for a thoroughbred, value-for-money middleweight.

Engine Technical Highlights

• 600cc liquid-cooled inline 4-cylinder 4-valve DOHC
• Redesigned inlet and exhaust
• Newly-developed high-compression cylinder head
• Slimmer inlet ports
• Revised cam profile
• Tuned for strong and linear low to mid-range torque
• One-piece cylinder and upper crankcase
• Rider-friendly linear power characteristics
• Bore x stroke 65.5 mm x 44.5 mm
• Lightweight forged aluminium pistons
• Four-hole two-direction fuel injection system
• 4-2-1 exhaust with midship muffler located beneath chassis
• 3-way catalyzer and exhaust O2 sensor
• New inner-push type clutch for easy action
• Redesigned shift mechanism for smooth and easy gearchanging

Chassis

Newly-designed tubular steel diamond-type frame

In order to be able to offer XJ6 Diversion riders strong all-round running performance, together with a low seat height and slim overall chassis dimensions, we have developed an all-new diamond-type frame. Manufactured from high tensile steel pipes which are 31.8 mm in diameter and 2.3 mm thick, this attractive new frame features a very simple and neat design which has been created using the minimum number of bends and welds.

The inline-4 cylinder engine is supported at four points on the frame by means of rigid mounts, and by using the 600cc powerplant as a stressed member of the chassis, our designers have been able to create an attractive and simple frame layout.

This new frame delivers easy handling combined with impressive ride quality. For smooth cornering performance and increased surface feedback, the lateral rigidity balance of the new frame has been optimized, giving a responsive handling package that instils confidence.

Dimensions and geometry chosen to deliver optimum balance

Featuring a 1,440 mm wheelbase together with a caster angle of 26 degrees and trail of 103.5 mm, the chassis geometry is designed to give balanced and predictable handling characteristics which respond in proportion to the rider’s inputs.

This 1:1 handling relationship is one of the most significant facets of the new XJ6 Diversion’s character, and its rider-friendly chassis performance looks set to ensure that this new bike quickly establishes itself as one of the most complete and most attractive models in the 600cc class.

New 41mm diameter front forks

To complement the new slimline tubular chassis, the XJ6 Diversion is equipped with newly-designed conventional front forks featuring 41 mm diameter tubes which deliver a good balance of rigidity together with excellent shock absorption characteristics.

In order to achieve good cushioning performance as well as accurate feedback from the road surface, these new smooth-action forks feature an aluminium upper triple clamp and a forged steel lower triple clamp.

Monocross rear suspension

A lightweight and compact new Monocross rear suspension system is fitted to the XJ6 Diversion, and, like the midship muffler, it plays an important role in helping to centralize mass and ensure easy handling characteristics.

This proven system features a new rear shock that is designed to give a smooth ride together with class-leading roadholding, making the XJ6 Diversion a strong performer in virtually every situation.

New lightweight cast wheels

Yamaha’s engineers have gone to great lengths to centralize mass with the use of lightweight components, thereby ensuring that the XJ6 Diversion delivers responsive and enjoyable handling performance.

The newly-designed lightweight cast aluminium wheels deliver an optimum balance of strength and rigidity, and their low weight also enhances the front suspension performance by minimizing unsprung weight. Their lightweight design also optimizes the gyroscopic moment around the front of the machine, and this contributes to agile and easy handling.

The new lightweight wheels are fitted with a 120/70-ZR17 tyre at the front, and a 160/60-ZR17 rear tyre, and these radial tyres give high levels of roadholding and traction.

Lightweight 520 chain

For reduced frictional losses the new XJ6 Diversion is equipped with a lightweight 520 chain. This lighter chain helps reduce drag for the efficient transmission of the engine’s power to the rear wheel, and the new 520-compatible front and rear sprocket designs also contribute to the reduced drag and frictional losses. In addition, the XJ6 Diversion benefits from a smaller diameter 17 mm rear axle for reduced unsprung weight, and all of these measures make a significant contribution towards overall weight reduction.

Slimline box-section swingarm

The new swingarm is manufactured from box-section steel pipe which offers a superior balance of rigidity. The bracket that supports the swingarm is located inside the swingarm, and this feature makes for a slimmer body design.

Lightweight and superior feeling brake system

Further weight savings can be seen in the front brake system, which consists of dual 298 mm diameter discs. Compared to the FZ6, the XJ6 Diversion’s discs are 0.5 mm thinner, giving an unsprung weight reduction of about 180g overall, and the twin-piston calipers are equipped with new hoses which feature an optimized coefficient of expansion, giving enhanced operation and feel.

The 245 mm diameter rear disc is slowed by semi-metallic pads which are designed to offer smooth braking for easy controllability. The rear braking system also features a special relationship between the rear brake pedal lever ratio and the return spring, where the spring rate has been specifically chosen to allow the rider to generate braking power that is in direct proportion to the amount of brake pedal depression.

ABS anti-lock braking system

The new XJ6 Diversion is also available with a compact new lightweight ABS design. This new system has been developed to offer improved feel when activated, and features a linear control (3-position) ABS, instead of the previous two mode system, which operated in ‘increased brake pressure’ and ‘decreased brake pressure’ modes.

With the new linear ABS, the brake system’s hydraulic pressure is instantaneously varied according to the slip ratio of the wheels, and this gives a smoother and more stepless feel when the system is activated. The new system also gives a more natural feel to the braking system when the ABS is not functioning.

New magnetic sensors are used in place of the previous system’s sintered alloy.
Overall the new ABS unit and the front and rear sensor rotors give an unsprung weight reduction of 1,320g.

Timeless next-generation pleasure-sports styling

The styling on the new XJ6 Diversion is designed to capture the spirit of this outstanding new motorcycle, which can be summarized as being ‘a pleasure sports model with brisk performance that can be easily handled’.

For added wind and weather protection the XJ6 Diversion benefits from a lightweight half cowl which gives the bike a sleek and sporty profile.

The three key themes which the styling aims to convey are:

• Rider-friendly engine and chassis performance
• Real-world middleweight
• Timeless and exciting design

Two of the most significant aspects of the new XJ6 Diversion’s body design are the minimalist tubular steel frame, and the slimline swingarm which features an inner-bracket layout. These structures are the main influence on the look and character of the bike – from whichever angle it is viewed – and their design is complemented and reflected in many other components, creating a unique and original appearance for this next-generation middleweight.

The short midship muffler accentuates the feeling of the bike’s strong concentration of mass, which is further emphasised by the slim swingarm and lightweight front and rear wheels. With its hexagonal shape, the narrow-waisted fuel tank looks special from every angle, and the flowing tubes on the minimalist diamond-type frame blend with the rest of the machine to give the XJ6 Diversion a very attractive, timeless and stylish appearance.

New instrumentation

Complementing the exciting and timeless styling of the new XJ6 Diversion is a comprehensive new instrument panel featuring a digital speedometer, analogue tachometer, odometer/tripmeter, fuel gauge, and a coolant temperature gauge.

Chassis Technical Highlights

• Newly designed high-tensile steel diamond-type frame
• Idealised balance of lateral rigidity for strong cornering performance
• 1,440 mm wheelbase
• Wind-beating half-cowl
• Easy-handling caster angle of 26 degrees and 103.5 mm trail
• Hexagonal slimline fuel tank with comfortable knee-grip area
• New slimline swingarm with inner bracket design
• 41 mm diameter conventional front forks
• Monocross rear suspension
• Lightweight 298 mm front discs and 245 mm rear disc, thickness 4.5 mm
• 120/70-ZR17 front tyre and 160/60-ZR17 rear tyre
• Lightweight, low-drag 520 chain (FZ6 is 530)
• Newly-designed lightweight cast wheels
• Timeless new styling emphasises concentration of mass
• Linear-control ABS available as an option
• New multi-function instrumentation
• Adjustable handlebar position

Colours both XJ6 Diversion and XJ6 Diversion ABS

• Ocean Depth
• Graphite
• Lava Red

Accessories

Yamaha will offer a range of accessories created specifically for the XJ6 Diversion, and the line-up will be available from authorized Yamaha Dealers. The accessory range will include:

• Aluminium rear carrier 46-litre top case
• Engine guard Inner bag for top case
• Roller protectors Back rest for top case
• Flip-up screen City tank bag
• Tank pad

Technical Specification

Engine

• Engien Type - Liquid cooled, 4-stroke, forward-inclinedparallel 4-cylinder, 4-valves, DOHC
• Displacement - 600 cc
• Bore x stroke - 65.5 x 44.5 mm
• Compression ratio - 12.2:1
• Max. Power - 57.0 kW (78 PS) @ 10,000 rpm
• Max. Torque - 59.7Nm (6.1 kg-m) @ 8,500 rpm
• Lubrication system - Wet sump
• Fuel supply system - Fuel injection
• Clutch type - Wet, multiple-disc
• Ignition system - TCI
• Starter system - Electric
• Transmission system - Constant mesh 6-speed
• Final transmission system - Chain
• Primary reduction ratio - 86/44 (1.955)
• Secondary reduction ratio - 46/16 (2.875)
• Gear ratio, 1st gear - 37/13 (2.846)
• Gear ratio, 2nd gear - 37/19 (1.947)
• Gear ratio, 3rd gear - 28/18 (1.556)
• Gear ratio, 4th gear - 32/24 (1.333)
• Gear ratio, 5th gear - 25/21 (1.190)
• Gear ratio, 6th gear - 26/24 (1.083)

Chassis

• Frame - Diamond shaped
• Front suspension - Telescopic fork
• Front wheel travel - 130 mm
• Rear suspension - Swingarm (mono cross)
• Rear wheel travel - 130 mm
• Caster angle - 26º
• Trail - 103.5 mm
• Front brake - Dual discs, Ø 298 mm
• Rear brake - Single disc, Ø 245 mm
• Front tyre - 120/70 ZR17M/C (58W) (tube less)
• Rear tyre - 160/60 ZR17M/C (69W) (tube less)

Dimensions

• Overall length - 2,120 mm
• Overall width - 770 mm
• Overall height - 1,210 mm
• Seat height - 785 mm
• Wheelbase - 1,440 mm
• Min. ground clearance - 140 mm
• Wet weight (including full oil and fuel tank) - 216 kg
• Fuel capacity - 17.3 litres
• Oil capacity - 3.4 litres

Specification are subject to change without notice, in accordance with national regulation and legislations