CRF450R
CRF450R
Rubber-mounted Renthal 971 bend aluminium
handlebar with two different mounting positions
and Works-type handlebar grips
New Works-type multi-map CDI system
produces optimum power curve for each gear
Lightweight titanium exhaust header
with new tapered head pipe and
repackable aluminium silencer
Compact new Honda Progressive
Steering Damper (HPSD) smoothes
handling for reduced fatigue
Washable two-stage foam air filter
for optimal engine protection
and easy maintenance
Long-travel, 47mm Showa inverted
twin-chamber cartridge-type fork
Pro-Link rear suspension
system features fully
adjustable Showa damper
with new settings
Dunlop 742FA front and
756 rear tyres offer optimal
traction and cornering feel
Removable rear sub-frame
allows easy maintenance
Front disc brake cover
helps protect rotor
and calliper from damage
HRC Works-type rear brake
Compact dual-piston
calliper front brake with
anodised aluminium
brake pistons and
lightweight rotor
Wide, cleated, self-cleaning stainless steel footpegs
Powerful 449cm3 liquid-cooled 4-stroke 4-valve Unicam engine
with magnesium ACG cover, clutch cover and cylinder-head cover
Lightweight and rugged
twin-spar aluminium frame
HRC Works-type aluminium spoke
nipples for reduced unsprung weight
All specifications are provisional and subject to change without notice.
2008 I CRF450R I Press Information
CRF450R
2008
Press Information
UK-EN – 1/7
CRF450R - 2008
Introduction
Features and Benefits
Honda’s all-conquering CRF450R has become
the overwhelming first choice of motocross, flattrack and
Supermoto riders around the world who’ll settle for
nothing less than the best of the breed to carry them to
victory. Powered by a remarkable Unicam 4-stroke
engine that pumps out roost-raising leaps of
performance at the twist of its throttle, the CRF450R’s
light and rigid aluminium frame and responsive Works
racer suspension systems are now complemented by
a revolutionary new Honda Progressive Steering Damper
(HPSD) for an unbeatable combination of quick,
confident control that makes this overwhelming class
favourite one of the best-handling dirt bikes you’ll find
anywhere.
New for 2008
Colours
• Extreme Red (with White number plate and
sidecovers)
• New tapered exhaust head pipe improves low-end
and midrange power.
• New lighter weight counter-balancer shaft and drive
gears.
• New Works-type multi-map CDI system uses
transmission gear-position sensor to provide specific
ignition maps for 1st gear, 2nd gear and 3rd through 5th,
and produces optimum power curve for each gear for
stronger torque feel in 1st gear, a wider powerband for
2nd gear and stronger throttle response and high-end
torque in the top three gears.
• Rev limit increased 50rpm to 11,270rpm.
• Friction-reducing coating on the clutch basket, clutch
centre and pressure plate improve clutch life and clutch
feel.
• Lightweight and compact new Honda Progressive
Steering Damper (HPSD) developed by Team
Honda for improved cornering ability and reduced rider
fatigue. HPSD features a compact and rugged hydraulic
damper attached between the steering head and
the lower triple-clamp to augment more aggressive
steering characteristics and assist straight-line handling.
The damper’s progressive damping action smoothly
increases with handlebar deflection, which produces
very natural steering characteristics and feel.
• New front fork triple-clamps feature 22mm offset for
improved cornering.
• New Showa fork features a larger cartridge rod and
new cartridge oil piston for improved oil flow and less
friction, plus stiffer springs for improved mid-stroke
action.
• New rear damper valving matches changes to front
fork.
• New Works-style front and rear brake rotors reduce
unsprung weight.
UK-EN – 2/7
CRF450R - 2008
Engine/Drivetrain
• Powerful 4-stroke 4-valve Unicam engine churns out
41kW of power at 9,000rpm and 50Nm of torque at
6,500rpm. Power is produced across a wide rpm-band
for easy-to-control operation.
• Liquid-cooled 449cm³ Unicam engine pumps out
nearly 90kW per litre while maintaining Honda’s
legendary simplicity and dependability.
• Innovative Unicam valve train provides both the light
weight of a compact single-cam drive and an optimum
combustion chamber shape for maximum power at all
engine speeds.
• Unicam valve train features a single carburised
camshaft directly actuating two 36mm titanium intake
valves. The camshaft’s centre exhaust lobe actuates two
30mm steel exhaust valves via a forked, low-friction,
roller rocker arm. A separate cam holder contributes to
the compact design, which allows a remarkable 21.5°
included valve angle while saving weight over
comparable DOHC systems.
• Lightweight titanium intake valves permit use of
smaller valve springs and reduce overall engine height.
• Forged slipper piston is 130g lighter than conventional
designs, for quick-revving response while maintaining
excellent cylinder sealing and high-rpm power.
• Lightweight NiCaSil cylinder lining ensures cooler and
quieter operation for extended engine life.
• Auto decompression and hot restart system make
starting easy in all conditions.
• 41mm FCR-type carburettor features four rollers on
the flat slide, resulting in light throttle effort, smooth
operation, crisp throttle response and excellent
rideability.
• Fully electronic Capacitor Discharge Ignition (CDI)
features 8-bit digital CPU for highly accurate ignition and
maximum performance.
• Twin-sump lubrication system separates oil supply to
crankshaft, piston and valve train from clutch and
transmission. This ensures a steady supply of cool oil to
the clutch, eliminates clutch and transmission material
contamination of the engine oil, and reduces
the amount of circulating oil along with the oil pump size.
• Exhaust system features lightweight titanium exhaust
header and heat shield. Repackable aluminium silencer
features stainless steel pipe and long-lasting silencer
packing.
• Gear-driven balancer reduces vibration while also
driving the water pump.
• Eight-plate clutch provides ample surface area to
handle the engine’s massive torque, while carefully
matched clutch springs provide a light feel at the lever.
Chassis/Suspension
• Fourth-generation twin-spar aluminium frame features
forged aluminium steering head and tapered down-tube
section designed for optimised frame rigidity. Tall
swingarm pivot plates and thin frame spars create
a narrow overall frame cross-section for superb rider
comfort and manoeuvrability.
• Front and rear wheels feature HRC Works-type
aluminium spoke nipples for reduced unsprung weight.
• Front wheel features large-diameter front axle and
wide wheel-bearing span for excellent rigidity.
• Rear axle diameter of 25mm and large-diameter
bearings provide significant rigidity and strength to
withstand torturous track conditions.
• Lightweight, 47mm Showa inverted twin-chamber
cartridge-type fork with aluminium dampers. Fork offers
315mm of travel and 16-step rebound and compression
damping adjustability. Front fork outer-tubes receive
same inner surface honing treatment as Works bikes for
low-friction operation.
UK-EN – 3/7
CRF450R - 2008
• Pro-Link rear suspension system features single fully
adjustable Showa rear damper with new damper
settings, 320mm of wheel travel, separate low-speed
(13-step) and high-speed (3.5 turns) compression
damping adjusters and 17-step rebound damping.
• Aluminium Renthal 971 bend handlebar rubbermounted to reduce rider fatigue and improve comfort.
• Large 50mm-diameter rear damper piston provides
consistent performance under demanding riding
conditions.
• Works-type handlebar grips add to rider comfort.
• Compact dual-piston front brake calliper designed for
over 30g lighter weight than conventional types.
• HRC Works-type rear brake system integrates
the rear master cylinder and fluid reservoir, eliminating
conventional external reservoir and hose.
• Link-type front brake master cylinder provides strong
braking control in combination with a lightweight brake
rotor.
• Large, Works-style 240mm front and rear disc brake
rotors.
Additional Features
• Handlebar holders provide two different mounting
positions to match rider preference.
• Dunlop 742FA front and 756 rear tyres provide
improved traction and cornering feel.
• Front disc brake cover helps protect rotor and calliper
from damage.
• Removable rear sub-frame allows easy maintenance.
• Washable, two-stage foam air filter for optimal engine
protection and easy maintenance.
• Re-packable silencer for maximum performance and
minimal noise.
• Comfortable, durable controls and high-quality
fasteners.
• Stainless steel clutch cable for long-life operation.
• Frame design allows sidecovers to have larger air
intake ducts, contributing to significant air flow increase
in the mid- and upper-rpm ranges.
• Honda Racing-inspired colours and graphics.
• Rider ergonomics are optimised by adapting
the handlebar, seat and footpeg height to place
the rider’s legs at the narrowest cross-section of
the frame for improved comfort and handling feel.
A revolutionary application of steering damper
technology creates a new level of agile handling
• Brake pedal and shift lever designed to complement
the riding position. Brake pedal features optimised ratio
to match integrated rear-brake master cylinder design.
• Wide, cleated stainless steel footpegs are selfcleaning, corrosion-resistant, provide excellent grip and
fold for extra ground clearance.
Honda Progressive Steering Damper
If you think you already know a lot about steering
dampers, get ready to think again. With a stroke of fresh
engineering insight, the hard-working minds at
Honda have created the Honda Progressive Steering
Damper (HPSD), a new application of steering damper
technology designed specifically to augment more
aggressive turning characteristics rather than only
assisting straight-line handling, as has been the case with
steering dampers in past applications.
• Rear brake pedal and shift lever made of lightweight
aluminium.
• Adjustable front brake lever for maximum control.
• Quick-adjust clutch perch for easy cable adjustment.
UK-EN – 4/7
CRF450R - 2008
With the integration of Honda’s new HPSD, the 2008
CRF450R and CRF250R both demonstrate a higher level
of front-end traction with significantly enhanced steering
feel, specifically a more “planted” feel in turns for better
front-wheel control, especially under dry, hard-packed
track conditions. Net result: greater cornering speed,
a higher level of front-end confidence and reduced rider
fatigue thanks to this damper’s astounding new turning
ease. Additionally, HPSD enhances handling in whoops
and fast sections of the track, all of which combine to
speed up lap times over the entire course of a race.
The earliest versions of HPSD first saw action aboard
the American Honda Racing Team’s CRF450R and
CRF250R race bikes during the 2004 AMA Supercross
series. Initial response from team riders was
overwhelmingly positive. Additional testing confirmed
just how versatile the system could be under a wide
range of tracks and riding conditions. From here
the stage was set for the prototype HPSD to see action
at the highest levels of Supercross and Motocross racing
for the entire 2004 season.
Thus equipped, the CRF450R found remarkable
success in AMA Supercross and went on to sweep every
AMA motocross win during the 2004 outdoor Motocross
season, a high-water mark in the history of the sport.
Ongoing development work saw HPSD installed on
Honda Works motocrossers through the 2007 season,
including Europe’s highly successful World Motocross
contenders, Team Martin Honda. This intensive four-year
period of development and testing of various damper
settings under top-level racing conditions led to
a finalised design and integration on the 2008 model year
CRF450R and CRF250R.
HPSD has given Honda’s engineers the ability to create
more aggressive chassis geometry for increased agility
without compromising machine stability. Accordingly,
the CRF450R and CRF250R both feature revised
steering geometry for 2008, thanks to a change in fork
offset via their new triple-clamps. For example,
the change from 24mm of offset to 22mm alters
the CRF450R’s steering trail from 109.4mm on
the 2007 model to 111.4mm for 2008, which reflects
the front-end being tucked in 2mm closer to
the engine. This change also shortens the wheelbase by
2mm. This change results in even quicker turning
characteristics and improved front-end traction, thus
allowing the rider to hold the line more easily in tight
corners. Moreover, while in mid-turn—and virtually
everywhere else on the track—HPSD damps out a lot of
the jarring that normally tries to deflect the front wheel.
Subsequently the rider doesn’t need to work as hard to
hold a line. In the past, pulling 2mm from the steering offset and shortening the wheelbase might have sacrificed
handling, but with HPSD, riders get the best of both
worlds: quicker steering and better handling, especially
at higher speeds.
HPSD consists of a very compact and very clever
damper mounted behind the front number plate.
Weighing a mere 6.5 ounces, it attaches between
the lower triple-clamp and the steering head.
The damper offers 15 clicks of adjustability and is also
completely rebuildable. Its small size permits it to be
tucked behind a newly styled number plate that protects
it from flying debris.
To complement the addition of HPSD, the steering head
was completely redesigned and re-tuned for correct flex/
stiffness properties, and an HPSD mounting lug was
incorporated. Likewise, the triple-clamps were newly
designed to yield the correct degree of stiffness, given
the new forces imparted by the steering damper system.
Given the interrelated nature of the forces acting on this
latest iteration of Honda’s highly sophisticated fourthgeneration aluminium frame, every force input was
carefully calculated and matched so that the chassis,
suspension and HPSD all worked in concert as one
system. In short, HPSD is not merely a bolt-on damper.
UK-EN – 5/7
CRF450R - 2008
As the name Progressive Steering Damper infers,
the damping action of the unit increases over the range
of travel. From the steering head’s neutral position to
approximately five degrees of movement in either
direction (which are very small off-centre changes),
HPSD exerts minimal damping force, resulting in neutral
steering during straight-line running. As handlebar
movement increases and further extends the damper
rod, damping force smoothly increases to produce very
natural steering characteristics and feel.
To achieve this natural steering feel, HPSD’s damping
rates differ in the two directions of travel; under extension
when the handlebar is turned away from centre, damping
forces are significantly greater. Under compression as
the handlebar returns to the straight-ahead position,
HPSD offers less resistance. In addition, at about
the one-third point on the extension throw,
a position-sensitive damping circuit opens and
progression of the damping action lessens.
This additional passageway, which in cutaway view looks
like a small channel machined into the damper body,
moderates the damping force under more extreme
handlebar angles. In addition, the damping mechanism
is speed sensitive, relative to the speed of handlebar
movement and wheel deflection; as sharp impacts cause
the front-end to rapidly deflect, HPSD provides
proportionally greater damping force. Yet when
the rider places steering input through the handlebar,
the damping action feels negligible and entirely natural.
In addition, Team Honda riders have discovered that use
of HPSD permits the use of distinctly stiffer front
suspension settings than had been possible without
the steering damper. The addition of HPSD offered riders
another opportunity to fine-tune their machines in new
ways to match various riding conditions. Proof once
again that the entire chassis is a highly tuned system that
must be designed and adjusted as a whole. Subsequent
testing for the 2008 CRFs confirmed this for production
bikes as well, and, as a result, the new CRF450R and
CRF250R both feature slightly stiffer springs and revised
compression and rebound damping rates in the fork.
With HPSD, the 2008 CRF450R and CRF250R feel just
as stable through fast whoops as the 2007 model did
with its more conservative fork offset, yet steering for
both new bikes is markedly quicker, and remarkably
easier on the rider. When the front-end impacts an
obstacle off-centre and the handlebar begins to kick out
in response, HPSD automatically lends a steadying
degree of damping. As a result, these 2008 models feel
distinctly easier to ride; not only offering precise steering
action that inspires confidence, but also remarkably
smooth and responsive, allowing the rider to more easily
steer in and out of ruts and take other lines at will.
In short, the Honda Progressive Steering Damper reflects
once again the benefits of innovative engineering. By
fundamentally moderating the manner in which outside
forces affect a bike’s steering, HPSD now extends
Honda’s ability to elevate the sport to the next level.
The location of the HPSD unit also creates what is in
effect a rising-rate mechanical stroke for the damper rod
travel without the need for a complicated linkage. As
the handlebar arcs toward the steering stops,
the increased degree of turning produces increasingly
larger amounts of travel from the shock on
the extension stroke. Hence, a rising rate relationship in
shock stroke versus handlebar movement. Net result:
a very natural steering feel along with the bonus of added
damping assistance as the handlebar moves farther from
center.
UK-EN – 6/7
CRF450R - 2008
Specifications
Suspension
General
Model
Front
47mm Showa inverted leading-axle twinchamber cartridge-type telescopic fork with
16-step adjustable compression and rebound
damping; 315mm axle travel
Rear
Pro-Link with Showa damper, adjustable lowspeed (13-step) and high-speed (3.5-turn)
compression and 17-step rebound damping;
320mm axle travel
Type
Front
Aluminium rim/wire spoke
Rear
Aluminium rim/wire spoke
Rim Size
Front
21 x 1.60
Rear
19 x 2.15
Front
80/100 21 (51M)
Rear
110/90 19 (62M)
Front
240mm hydraulic disc with dual-piston
calliper and sintered metal pads
Rear
240mm hydraulic disc with single-piston
calliper and sintered metal pads
CRF450R
Mold Type
ED-type
Type
Engine
Type
Liquid-cooled 4-stroke 4-valve SOHC single
Displacement
449cm³
Bore x Stroke
96 x 62.1mm
Compression Ratio
12 : 1
Max. Power Output
37.8kW / 9,000min-1 (95/1/EC)
Max. Torque
46.9Nm / 7,000min-1 (95/1/EC)
Wheels
Fuel System
Carburation
41mm Keihin FCR flat-slide carburettor
Fuel Tank Capacity
7.2 litres
Electrical System
Tyre Size
Brakes
Ignition System
Computer-controlled digital capacitor
discharge with electronic advance
Starter
Primary kick
Drivetrain
Transmission
5-speed
Primary Reduction
2.739 (63/23)
Gear Ratios
1.800 (27/15)
2
1.470 (25/17)
3
1.235 (21/17)
4
1.050 (21/20)
5
0.909 (20/22)
Final Reduction
3.692 (48/13)
Final Drive
#520 roller chain
Type
Frame
Type
Semi-double cradle; aluminium twin-spar
Chassis
Dimensions
2,189 x 825 x 1,283mm
Wheelbase
1,489mm
Caster Angle
26° 76'
Trail
111.4mm
Seat Height
955mm
Ground Clearance
340mm
Kerb Weight
109kg
All specifications are provisional and subject to change without notice.
UK-EN – 7/7
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