2009 Yamaha XVS950A Midnight Star
All-new Yamaha XVS950A Midnight Star - Full-size
cruiser performance with a lightweight feel
Powered by a newly-designed 942cc high-torque air-cooled
V-twin SOHC engine housed in an easy-handling long-and-low
chassis, the all-new Yamaha XVS950A Midnight Star
brings an exciting and refreshing ‘new style
classic’ look to the sub 1,000cc cruiser category.
This unique and original new machine is aimed at
the customer who wants genuine ‘heavyweight’
cruiser style and gutsy V-twin torque combined with
punchy performance, light feeling handling and a rider-friendly
character. Until now, the choice for new riders looking
for a ‘real’ full-sized cruiser has been
limited to larger-capacity 1,000cc+ V-twin models
whose higher weight and bulkier bodywork can sometimes
be intimidating for less experienced bikers.
With its compact new high-torque air-cooled V-twin
engine, as well as a long and low chassis, a low seat
height, and class-leading modern styling, the easy-to-handle
Midnight Star 950 opens up a new chapter in cruiser
design. For 2009 those wild-at-heart riders of all
ages will have the chance to own a genuine V-twin
cruiser whose looks, image, character and performance
ensure that it delivers real street credibility.
Although the machine benefits from the use of advanced
Yamaha technology, great care has been taken to ensure
that this new bike retains the essential simplicity
of design that characterizes every classic cruiser.
For example, our engineers spent a great deal of
time tuning the new exhaust system in order to accentuate
the soulful low-frequency sounds and eliminate high
frequency noise. Likewise, much effort was put into
creating an efficient intake system which not only
enhances performance, but also emits a good intake
sound boost pulse feeling from low speeds right through
to the high speed range.
The new Midnight Star 950 runs with a large-diameter
18-inch front wheel in order to lighten the handling
feel and emphasize the bike’s image of lightness
– and for ease of use and enhanced controllability,
the fuel tank narrows considerably at the rear.
This extreme attention to every detail – however
small – is evident throughout the machine, and
the end result is a high quality machine which adds
a new dimension to the cruiser world. With its high-torque
V-twin air-cooled engine, steel fenders, belt drive
and long and low style – as well as new-style
classic cruiser looks and a simple, clean-cut design,
the all-new Midnight Star 950 delivers full-sized
performance with a lightweight feel and easy handling.
Engine
All-new high-torque 942cc air-cooled V-twin
4-valve SOHC design
In order to achieve the design team’s goals
of creating a new generation cruiser with a lightweight
feel and gutsy performance, the Midnight Star 950
is driven by a newly-designed high-torque 942cc air-cooled
V-twin 4-valve SOHC engine with fuel injection.
For optimum low to mid-range performance, the 942cc
engine runs with almost ‘square’ bore
x stroke dimensions of 85.0 mm x 83.0 mm, and the
highly efficient pent-roof combustion chamber delivers
a compression ratio of 9.0:1. (For comparison, the
Midnight Star 1300 features a bore x stroke of 100.0
mm x 83.0 mm, and a compression ratio of 9.5:1.) The
combination of a 4-valve head with a pent-roof combustion
chamber and a ‘square’ configuration gives
the engine a punchy torque output for strong acceleration
and rapid overtaking potential.
This compact new V-twin engine utilizes the same
three axes (crankshaft/front cylinder cam/rear cylinder
cam) as the larger-capacity Midnight Star 1300 to
give a compact V-bank, but it has a very different
power delivery character as a result of the elimination
of the balancer mechanism. By not equipping this new
V-twin with a balancer mechanism, our engineers have
been able to enhance the pulse feeling and also minimize
the new engine’s crankcase dimensions and weight.
In addition, the decision to adopt air cooling has
given our designers more freedom in creating a clean
and simple profile which further emphasizes the light
feel and image of this new-generation cruiser.
This gutsy new 942cc 60? V-twin also features state-of-the-art
internals, including lightweight forged pistons, a
ceramic plated cylinder and highly efficient 4-valve
cylinder head, as well as many newly-designed components
including cams, valves, throttle body, oil pump, crankshaft,
connecting rods, clutch, transmission gears, crankcase
cover and exhaust system.
Optimized squish area design
In any big-bore engine design, the combustion flame
must travel a greater distance than on a smaller bore
engine, and so in order to ensure high combustion
efficiency, the new Midnight Star 950 engine features
pent-roof combustion chambers with a specially-designed
squish area. By forcing the fuel/air mix towards the
centre of the combustion chamber more quickly, the
optimized squish area gives a faster combustion speed,
which gives stronger throttle response and higher
levels of performance.
60º V-twin engine design with uneven
firing interval
One of the most significant and defining features
to be found on the new 942cc V-twin engine is the
uneven firing interval. Combustion takes place at
300º and 420º, which makes for a distinctive
and pleasing engine pulse, and it is this uneven beat
that gives the new Midnight Star 950 such an appealing
and special character, as well as a gutsy exhaust
note.
In order to enhance the lightweight feeling with
pulse generated by the uneven firing sequence, this
new V-twin engine features no balancer shaft, which
not only strengthens the gutsy character, but also
makes for easy revving and strong response. Vibration
is minimized by the use of lightweight forged pistons
and connecting rods, and rubber mounts for the handlebars
and footboards ensures high levels of rider comfort.
Eliminating the balancer shaft also brings with it
a number of other advantages, including reduced gear
noise, lower engine weight, and more efficient engine
operation and better response thanks to a decrease
in pumping losses.
This compact new engine also features a 60º
cylinder bank, and this relatively narrow angle between
the two air-cooled cylinders contributes to the bike’s
concentration of mass, which accentuates the lighter
handling feeling – a central theme of this new-generation
cruiser’s very special character.
Specially-shaped cylinder fins
The Midnight Star 950’s muscular looking air-cooled
V-twin engine is the focal point of this new-generation
cruiser, and the beautifully-designed cylinder fin
layout adds to the appeal of the classic V-twin architecture.
By shaping the fins so that those at the top of the
cylinder are wider than those at the base, each cylinder’s
fin outline creates a V-form, with the sharp end of
the ‘V’ pointing towards the centre of
the crank axis.
This design feature underlines the classic cruiser
image of the Midnight Star 950, and is complemented
by the buff finish on the cylinder head fins to give
a handsome, high quality feel to the bike. Few engines
capture the original spirit of motorcycling as well
as the classic V-twin layout, and by specially shaping
the air-cooling fins to form a ‘V’ profile,
Yamaha’s designers have succeeded in creating
an authentic modern-day classic.
Right side-mounted air intake
The compact new 942cc V-twin has been developed
to produce strong low to mid-range torque with punchy
performance, and in order to ensure outstanding intake
efficiency a large-capacity 3-litre air cleaner box
is mounted on the right side of the V-cylinder block.
Featuring a triangular shape, and located between
the 60? V-bank, this stylish air box emphasizes the
V-twin configuration.
For optimal efficiency combined with a pleasing intake
sound, particular attention has been paid to the design
of the ducting which has been specially tuned to produce
the right note. At lower speeds the intake emits a
throaty burble, while at higher speeds the intake
note complements the exhaust sound to accentuate the
engine’s pulse feel.
Fuel injection
For strong performance across the rpm range, together
with minimized emissions, the 4-valve cylinder head’s
pent-roof combustion chambers are fed by a sophisticated
4-hole, 2-directional fuel injection system. Equipped
with a 35 mm diameter throttle body, these injectors
aim the spray directly at the valve surfaces which
ensures good atomization of the fuel for faster and
more complete combustion.
Various sensors transmit data on air temperature,
atmospheric and intake air pressure, engine temperature,
crank position, speed, throttle position and exhaust
oxygen levels to the ECU which then adjusts the fuel
injection system to ensure optimal combustion efficiency.
This system is designed to offer excellent drivability
together with instant response and efficient operation,
and for outstanding idling stability which is set
at 950-1050 rpm, an Idle Speed Control (ISC) valve
is fitted.
Forged aluminium pistons and ceramic composite
plated cylinders
In addition to its high performance 4-valve cylinder
head design and highly efficient fuel injection system,
the latest addition to Yamaha’s cruiser family
benefits from new lightweight forged aluminium pistons.
As well as being immensely strong, the Midnight Star
950’s compact forged pistons also help to reduce
reciprocating weight, which in turn makes for a smoother
running engine and also makes for excellent throttle
response.
The running efficiency of these lightweight forged
pistons run is further enhanced by the use of ceramic
composite plated cylinders, which ensure more effective
heat dissipation, and also help to minimize oil consumption.
Roller rocker arm for smoother engine performance
This new-generation cruiser benefits from a number
of design features aimed at enhancing both the feel
and the performance of the new V-twin engine, including
the elimination of the balancer, as well as the adoption
of an uneven firing sequence and the fitment of an
efficient fuel injection system.
Another important feature which plays a vital part
in making this one of the most impressive performers
in the class is the roller rocker arm valve lift mechanism.
The Midnight Star 950’s advanced rocker arm
design features a revolving slipper mounted on a needle
roller bearing, which dramatically reduces the friction
normally generated between a conventional slipper
and the cam – which features a tough Isonite
coating for optimum engine performance. In addition
to reducing frictional losses, this roller rocker
arm also permits the use of a cam and valve spring
design that gives a softer valve seating speed. Another
advantage is that valve overlap can be reduced for
stronger low to mid-range performance, and exhaust
emissions can also be cut.
Right-side exhaust system with 2-1 muffler
and 3-way catalytic converter
The exhaust system has been developed to complement
the new fuel injection system’s settings, and
features a neat 2-1 design running along the bike’s
right side. The muffler is a simple two-stage expansion
type design which has been designed to accentuate
the feel and character of the engine’s uneven
firing sequence, and to give a good strong pulse in
the low to mid-range.
This compact and minimalist two-into-one exhaust
system is equipped with an oxygen sensor which transmits
data to the ECU to ensure the optimal fuel/air mix
is injected for efficient combustion, and a 3-way
catalytic converter ensures that this new V-twin surpasses
EU3 requirements.
The distinctive beat of the engine is one of the
most striking features of the new Midnight Star 950,
and the quality of the bike’s exhaust note is
the result of intensive testing. Our engineers have
developed a system in which high frequency sounds
have been eliminated, and the low frequency note was
accentuated, in order to ensure a gutsy and evocative
exhaust note.
Smooth-shifting 5-speed transmission
The new Midnight Star 950’s transmission has
been designed specifically to accentuate the gutsy
character of the new air-cooled V-twin engine. The
five gear ratios have been carefully chosen so that
they enable the rider to enjoy fully the bike’s
remarkably strong low to mid-range torque wave, and
fifth gear has been set to deliver relaxed and comfortable
cruising.
The gears also feature a straight-cut type dog design
for even smoother shifting, and this – together
with the instant supply of torque at the twist of
the throttle – makes for a relaxing and enjoyable
riding experience, together with spirited acceleration.
Engine - Technical Highlights
- All-new 942cc air-cooled V-twin 4-valve SOHC
engine
- Bore x stroke 85 mm x 83 mm
- 9.0:1 compression ratio
- Compact 60º V-twin design
- Uneven firing interval at 300º and 420º
- Characterful pulse feeling
- Pent roof combustion chambers
- Strong low to mid-range torque
- Elimination of balancer shaft for reduced weight
and stronger engine pulse feeling
- Specially-shaped tapered cylinder fin layout
for classic V-twin style
- Right side-mounted air intake with tuned induction
noise
- Large-capacity 3-litre air cleaner box
- Efficient fuel injection for instant response
and reduced emissions
- Optimized squish area design for efficient combustion
- Forged aluminium pistons and ceramic composite
plated cylinders
- Roller rocker arms for smoother engine performance
- Right-side 2-1 muffler and 3-way catalytic converter
- Smooth-shifting 5-speed transmission with straight-cut
gear dogs
Chassis
New-design double-cradle steel frame
The Midnight Star 950’s new double cradle
frame has been designed to deliver a lightweight handling
feeling, and this has been achieved by designing a
structure which offers varying degrees of rigidity
in different areas in order to achieve an idealized
rigidity balance. The new frame is especially rigid
around the head pipe area, whilst the torsional rigidity
is set at a relatively lower level in order to introduce
a degree of forgiveness into the handling characteristics,
which makes for high levels of surface feedback and
increased rider comfort.
The relationship between the frame’s torsional,
lateral and longitudinal rigidity levels has been
carefully selected by our engineers following extensive
testing, and the result is a chassis whose roadholding
and handling characteristics complement the performance
of the high-torque engine.
From an aesthetic point of view, the design of the
new double cradle frame projects an image of simplicity
and functionality, which perfectly matches the classic
lines of the new air-cooled V-twin powerplant. The
engine is mounted to the frame with rigid mounts,
with one at the cylinder head and three on the crankcase,
and by using the engine as a stressed member the overall
chassis weight can be minimized. The four rigid engine
mounts also help to accentuate the uneven firing pulse
feeling, to give a characterful and enjoyable riding
experience.
Long-wheelbase lightweight chassis
Running with a wheelbase of 1,685 mm, this new generation
Yamaha cruiser has the longest wheelbase in its class,
and although it measures only 5 mm less than the Midnight
Star 1300, the stylish new Midnight Star 950 is actually
a full 25kg* lighter than its bigger brother.
* Note: wet weight difference
Compared to other machines in its class, the Midnight
Star 950 delivers a much lighter and sportier handling
experience, and one of the major contributors to this
aspect of the bike’s character is the positioning
of the air-cooled V-twin engine. Compared to the larger
Midnight Star 1300, the new Midnight Star 950’s
engine sits further forward in the chassis to give
more weight over the front wheel for an optimized
front/rear weight distribution.
In addition to the sportier front/rear weight bias,
this new Yamaha cruiser features a caster angle of
32?10’, which, when combined with a trail of
145 mm and the increased front wheel weight loading,
ensures outstanding handling performance in a wide
range of conditions, from relaxed highway cruising
through to sporty riding on winding roads.
Low seat height
In order to ensure that the new Midnight Star 950
delivers the high levels of riding comfort and ease
of use that our designers set out to achieve, a low
seat height of only 675 mm is featured, compared to
715 mm on the Midnight Star 1300.
This newly designed seat is narrow at the front,
in order to match the slim rear section of the new
fuel tank, and this makes it easier for riders to
put their feet on the ground when stationary or riding
at low speeds in traffic jams. Combined with the tapered
fuel tank – as well as the angle of bend used
in the pull-back handlebars, and the position of the
footboards, this low seat gives a natural riding position
which enhances overall comfort and controllability.
18-inch front wheel with 130/70-18 tyre
Another important factor which makes a significant
contribution to the bike’s lightweight handling
and steering qualities is the use of an 18-inch front
wheel fitted with a relatively narrow 130/70-18 front
tyre.
One of the main goals of the Yamaha’s Midnight
Star 950 design team was to create a new type of cruiser
which would offer light and easy handling characteristics,
and the use of this narrower, lower profile 18-inch
front tyre is a key element in achieving these aims.
In classic cruiser tradition, a wide-section 170/70-16
tyre is fitted for optimal traction and excellent
rider and passenger cruising comfort.
Newly-designed aluminum wheels front and
rear
The newly-designed 8-spoke front and rear wheels
complement the bike’s classic, lightweight and
sporty cruiser design, and help to minimize the unsprung
weight for smooth and responsive suspension action.
The front wheel is 18 x MT3.50, while the rear measures
16 x MT4.50. Furthermore, the spokes feature a two-prong
design where they meet the rim, which accentuates
the image of lightness which characterizes this excitingly
different new cruiser.
Steel front and rear fenders
The new Midnight Star 950 is equipped with steel
front and rear fenders to underline its classic style.
At the front end the slimline fender features a short
front section and a flared rear end which accentuates
the size of the new larger-diameter 18-inch front
wheel, while the steel rear fender is cut horizontally
at mid-wheel height for a classic cruiser look.
Teardrop fuel tank with wide upper surface
By using 3D CAD techniques, Yamaha’s designers
have succeeded in creating a classic teardrop fuel
tank which looks light and slim, and yet has a sizeable
capacity of 17 litres. Viewed from the side, this
stylish tank has a low profile and looks extremely
slim – even though there is a built-in fuel
pump – giving this cruiser an even lighter look.
In traditional cruiser fashion, the teardrop shaped
fuel tank has a wide upper surface, and viewed from
above this beautifully sculpted design tapers towards
the rear to give a very slim section near the rider’s
knees, making it easy to get both feet on the ground.
The sharply tapered shape also underlines the bike’s
sporty image, and gives a visual expression of speed.
This new fuel tank is a distinctive styling element
to be seen on the Midnight Star 950, and it has been
manufactured using Yamaha’s exclusive pressing
technology which enables the production of increasingly
complex and intricate components.
A long and low body with a “New-Style
Classic” image
What sets this new cruiser apart from other designs
is its long and low profile which Yamaha describe
as the ‘New Style Classic’ image. Unlike
many other more traditionally styled cruisers where
the rider sits ‘in’ the bike in the ‘valley’
formed by the elevated fuel tank and the high pillion
seat and rear fender, the Midnight Star 950 rider
feels more like he or she is sitting ‘on’
the bike.
Viewed from the side, the horizontally-cut rear fender,
flat pillion seat and low profile fuel tank on this
new cruiser form a much flatter upper surface, in
a similar style to the ‘NeoStreamline’
design of the Midnight Star 1900.
The long, low and horizontal profile give the machine
an individual style, and accentuate the impression
of lightness. This image is strengthened by the apparent
simplicity of the tubular double-cradle frame’s
design, which features an abundance of space around
the head pipe area. The large-diameter front wheel
and its relatively narrow, low-profile tyre add to
the lightweight appearance, while the muscular looks
of the timelessly-styled air-cooled V-twin engine
with its beautifully sculpted fins reinforce the Midnight
Star 950’s ‘New-Style Classic’ looks.
Finally, the bike’s distinctive character is
underlined by the narrow, flared front fender, compact
headlight assembly, right side air-intake and simple
2-1 exhaust system.
Aramid-type belt drive
Like the larger capacity XVS/XV models, the new
Midnight Star 950 is equipped with a durable and efficient
belt drive system. Manufactured using aramid, this
28.6 mm wide belt drive is an extremely effective
way of transmitting the high levels of torque produced
by the V-twin engine, and its lightness makes it an
ideal match for a machine with such a long swingarm.
Offering excellent strength as well as good shock
absorbing properties and resistance to corrosion,
this low-maintenance belt drive system allows the
rider to enjoy the Midnight Star 950’s high-torque
and uneven firing pulses to the full.
Front and rear suspension systems with optimized
settings
The front and rear suspension systems are designed
to deliver a smooth, comfortable ride, together with
the ability to handle everything from highway cruising
with a passenger through to solo riding on twisty
back roads.
Equipped with 41 mm diameter inner tubes and giving
135 mm of travel, the conventional-type front forks
feature a wide pitch of 240 mm, and are offset by
45 mm. Although these heavy-duty forks appear externally
identical to the design featured on the Midnight Star
1300, the settings have been revised to suit the lighter
Midnight Star 950, and the spring rate is reduced
by around 27% to 5.4N/mm, which ensures smooth suspension
action and high levels of comfort.
Running with a caster of 32?10’ and a trail
of 145 mm, this high quality front end ensures good
manoeuvrability together with easy steering over a
wide range of riding speeds and surface conditions.
At the rear end is a bottom link-type Monocross system
which is similar to the design used on the Midnight
Star 1300, and offers 110 mm of rear wheel travel.
For high levels of rider and passenger comfort the
preload-adjustable rear suspension is designed to
offer a soft initial stroke which becomes progressively
firmer as the suspension is compressed further. Together
with the smooth-action front forks, this Monocross
rear suspension system ensures that the Midnight Star
950 delivers high levels of comfort and excellent
roadholding in a variety of situations.
Large-diameter 320 mm front disc brake
For smooth and strong braking performance a large-diameter
320 mm single front disc brake and 2-piston pin/slide
caliper is used. To ensure effective operation together
with accurate feel, close attention has been paid
to optimizing virtually every element of this lightweight
braking system’s design, including the lever
ratio, lever shape, master cylinder diameter, brake
hose expansion rate and caliper rigidity.
Compared to some heavier cruisers which feature dual-disc
front braking systems, the single large-diameter disc
featured on the lighter Midnight Star 950 offers reduced
unsprung weight for more responsive front suspension
action. In addition to the weight savings, the single
front disc also emphasizes the lightweight image of
this new cruiser.
This impression of lightness and simplicity is further
strengthened by the 298 mm diameter rear disc which
is equipped with an underslung caliper.
Cast aluminium upper triple clamp
For an optimum balance of strength and rigidity,
the upper triple clamp is manufactured from cast aluminium,
while the lower triple clamp is made from steel. This
combination of steel and aluminium clamps –
which is also used on the Midnight Star 1300 –
ensures a good steering feeling together with excellent
feedback.
New-design large-diameter instrument panel
Mounted on the new slimline fuel tank is a new-design
large-diameter instrument panel which is framed by
a wide chrome-plated cover which highlights the bike’s
classic style.
The panel includes an analogue speedometer, as well
as six indicator lights including fuel and oil level
warning lights – while the multi-function LCD
display features an odometer with two trip functions,
as well as a fuel trip meter and clock. There is also
a useful instrumentation illumination adjuster which
can be operated from the left side handlebar switch,
allowing riders to increase or decrease brightness
of the LCD displays to suit the conditions.
Chassis - Technical Highlights
- New-design double-cradle tubular steel frame
- 1,685 mm long-wheelbase, easy-handling chassis
- Low seat height of 675 mm
- 18-inch front wheel for light feeling steering
- 130/70-18 front tyre
- Newly designed lightweight 8-spoke aluminum wheels
front and rear
- Front wheel: 18 x MT3.50; rear wheel: 16 x MT4.50.
- Classic front and rear steel fenders
- Slim 17 litre tapered teardrop fuel tank with
wide and flat upper surface
- A long and low body with a “New-Style Classic”
image
- Front forks with 41 mm inner tubes giving mm135
mm wheel travel
- Bottom link type Monocross rear suspension giving
110 mm wheel travel
- Front and rear suspension systems with optimized
settings
- Large-diameter 320 mm front disc brake, 298 mm
diameter rear disc brake
- Cast aluminium upper triple clamp
- New-design large-diameter multi-function instrument
panel
- Belt drive system
Colours
- Ocean Depth
- Dark Red
- Midnight Black
Technical Specification
Engine
- Type - Air-cooled, 4-stroke, V-type 2-cylinder,
4-valve, SOHC
- Displacement - 942 cc
- Bore x stroke - 85.0 x 83.0 mm
- Compression ratio - 9.0:1
- Max. Power - 39.4 kW (54 PS) @ 6,000 rpm
- Max. Torque - 76.8 Nm (7,84 kg-m) @3,000 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, 5-speed
- Final transmission system - Belt
- Primary reduction ratio - 72/43 (1.674)
- Secondary reduction ratio - 70/30 (2.333)
- Gear ratio; 1st gear - 46/15 (3.067)
- Gear ratio; 2nd gear - 33/16 (2.063)
- Gear ratio; 3rd gear - 30/19 (1.579)
- Gear ratio; 4th gear - 34/27 (1.259)
- Gear ratio; 5th gear - 25/24 (1.042)
Chassis
- Frame - Steel double cradle
- Front suspension - Telescopic forks, Ø
41 mm
- Front wheel travel - 135 mm
- Rear suspension - Swingarm
- Rear wheel travel - 110 mm
- Caster angle - 32º 10'
- Trail - 145 mm
- Front brake - Single disc, Ø 320 mm
- Rear brake - Single disc, Ø 298 mm
- Front tyre - 130/70-18M/C 63H
- Rear tyre - 170/70B16M/C 75H
Dimensions
- Overall length - 2,435 mm
- Overall width - 1,000 mm
- Overall height - 1,080 mm
- Seat height - 675 mm
- Wheelbase 1- ,685 mm
- Min. ground clearance - 145 mm
- Wet weight (including full oil and fuel tank)
- 278 kg
- Fuel capacity - 17,0 litres
- Oil capacity - 4,3 litres
Specification are subject to change without notice,
in accordance with national regulation and legislations
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