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VFR
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VFR
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Almost unique in its Super Sporttouring orientation, the VFR750Fhas always sidestepped the ‘hard-core,’ performance-first image ofthe racer-replica superbikes (andtheir accompanying discomforts)for a more mature, rider-focusedapproach to the joys of Super Sportmotorcycling. A sporty machinewith all-round appeal, the VFR750Fhas found wide acceptance from a
broad cross-section of riders whoappreciate not only top performan-ce, but also the effortless handlingand long-term comfort that it hasconsistently offered.
In 1990, the VFR750F was fittedwith a more compact engine and an eye-catching cast aluminiumPro-Arm single-sided swingarm,which gave it a distinctively high-
tech look while offering precisehandling and the added benefit of easier rear wheel maintenance.1994 saw the VFR completely re-dressed in striking new aerodynam-ic bodywork that took many of itsstyling cues from Honda’s remarka-ble NR to more strongly emphasizethe VFR750F’s sporty character.
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First introduced in 1986, Honda’s ever-popular VFR750F has regularly beenhailed as one of the finest all-round motorcycles in the 750cm3 class—or mostany other class for that matter. Unlike many other single-purpose sports bikes,the VFR750F succeeded in bringing together a combination of smooth and strongperformance, quick and confident handling, peerless comfort in almost any rid-ing situation, and superb quality of execution that has won it singular praisein motorcycle publications the world over—and a dedicated following of riderswho will settle for nothing less.
VFR
Introduction
VFR
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Unchanged since then, the VFR750Fhas gradually come to be regardedas a bit conservative, and while its overall performance has alwaysbeen strong, its image has lost a bitof its high-tech appeal as other newmachines have come to the fore.Thus, ‘VFR’ fans have been patientlywaiting for a radical change in bothdesign and performance that wouldstill maintain the ‘user-friendly’nature for which the VFR750F has become well-known and loved.
Now, for 1998, that long-awaitedchange has finally come. The VFRblasts back into the limelight drivenby the same dynamic, high-techfuel-injected engine poweringHonda’s RVF Superbike racers to victory around the world.Featuring a lightweight and rigidnew ‘pivotless’ frame similar tothat first introduced on Honda’snew VTR1000F Firestorm, theVFR’s aggressive, high-tech newlook provides an unmistakable
forewarning of exhilarating rides to come. With these and other exciting new features, this new-generation VFR is a rolling show-case of Honda’s finest motorcycletechnology and as such is certain to re-establish itself as the standardof comparison in its class for yearsto come.
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VFR
Introduction
VFR
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Advanced Air Management DesignFeaturing approximately the samefrontal area as the current design,but with a significantly reducedcoefficient of drag and superiorwind protection for both rider
and pillion passenger, the fairing’sfront cowl incorporates a large central air vent that directs airunder the windscreen to raise theheight of the air stream hitting therider at higher speeds.
4
VFR
Styling Concept
With the aggressive look of its new dual multi-reflector headlight staring forwardin a look of aggressive determination, the VFR’s sleekly aerodynamic new bodywork gives dramatic emphasis to its well-established image of speed andunsurpassed quality.
VFR
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The fairing’s new design maintainsthe VFR’s same highly praised ri-ding position in the location ofits seat, handlebar and foot pegs,while the fuel tank’s knee grips and step area were made slimmerfor enhanced wind protection andgreater comfort. The front indica-tors were also integrated into theoverall design and are located at either side of the base of theheadlight. The VFR’s new, larger
front fender is modeled after theaerodynamic units currently used onthe CBR1100XX Super Blackbirdand the CBR600F. Its longer noseand deeper valances combine tocontribute greatly reduced air resis-tance for lighter, more responsivehigh-speed handling in tune with theVFR’s uniquely versatile character.
5
VFR
Styling Concept
Dimension Comparison
Dimension Comparison! New VFR@ Current Model
!@
709m
m (
715m
m)
385m
m (
384m
m)
380m
m (
378m
m)
797mm (834mm)
1194mm (1216mm)
1440mm (1470mm)
529mm (559mm)
VFR
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In an innovative system first intro-duced on the VTR1000F, the fullfairing’s side panels feature largevents that were specially designedto pull air through the VFR’s all-new side-mounted twin radiators.This design maximizes coolingefficiency by taking advantage ofthe large difference in air pressurebetween the higher-pressure fairingcavity and much lower-pressureouter fairing surface.
The VFR’s large-volume fuel tankfeatures a smoothly curved designwith indents for the knees ensuringoptimum riding comfort and posi-tioning ease under most riding con-ditions; qualities that have enjoyeda long tradition in the design of theVFR. The rear seat cowl features asleek, almost shark-like line termi-nating in a wide, uniquely designedtaillight lens that cleanly integratesthe turn indicators into its attrac-
tively modern form. The VFR’sdetachable rear seat cowl projectsan aggressive ‘solo machine’ lookthat conceals a broad, comfortableperch for pillion passengers.
Bolt-on rear hand grips feature adual-injection nylon compositionthat provides a comfortable handhold for pillion passengers.
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VFR
Styling Concept
VFR
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• A bright, solid red grabs atten-tion with a heart-pumping look ofexcitement that provides a perfectmatch for the VFR’s renownedSuper Sports image.
• In black, the new VFR projects an imposing look of power andperformance.
• Finally, a deep, high-tech metal-lic silver accentuates the fairing’scurves with the subtle play of lightand shadow, projecting an image of blistering performance andincomparable quality.
All three solid colour variationsprovide maximum visual impactwith few graphics to detract from the bodywork’s simple, attractive form.
Colours• Italian Red• Mute Black Metallic• Sparkling Silver Metallic
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The new VFR’s three colour variations give unmistakable expression to its long-held image of dynamic power and performance while emphasizing its bodywork’simpressive look of speed and unequalled balance of sports riding enjoyment.
VFR
Colouring Concept
VFR
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The engine powering the all-newVFR is essentially the same 90° V4engine introduced in the RC45/RVFin 1994 and used successfully inSuperbike racing the world over.Emphasizing major reductions insize, weight and friction, this newlarger bore and longer stroke
781cm3 engine delivers a largeboost in torque and an increase intop speed over the current modelthat ensures greater flexibility inmost riding situations.
The new engine’s side-mountedgear-driven valvetrain makes
possible closer cylinder spacing and eliminates one crankshaft journal for more compact overalldimensions and significant reduc-tions in weight and internal friction.Spring-loaded split gears within thecompact gear train also help reducemechanical noise.
8
VFR
Engine
!
Engine Performance Comparison
@
Engine Performance Comparison! New VFR@ Current model# Power Curve$ Torque Curve% Power Output (kW)^ Torque (Nm)& Engine Speed (rpm x 1,000)
Engine W idth Comparison
Engine W idth Comparison(showing crankshaft journals)! New VFR@ Current Model# Journal
Cam Gear Train
#
$
%
&
^
! @
#
VFR
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Besides its larger displacement,another major difference from theengine powering the RC45 is theVFR’s longer-stroke 180° crank-shaft, which was specially designedto offer a smoother, wider range ofperformance in order to provide amore VFR-like feeling of torqueyacceleration for everything fromSuper Sport to touring riding.
A large-volume aircleaner, smooth,straight, short-throw downdraftintake ports, steeper 26° valve
angles and the latest in map-typedigitally programmed ignitions all contribute to the new engine’sexceptional power potential. TheVFR’s strong, light-action hydraulicclutch uses eight 125mm frictionplates for a wider, more effectivesurface area to stand up to the V4engine’s enormous torque. This feedsthrough a reworked, smoother- shift-ing six-speed transmission. Since the new engine was intended to beincorporated as the central stressedmember of the VFR’s all-new
‘pivotless’ frame, its castings weredesigned for extra strength aroundtheir various attachment points, especially at the rear where thecrankcase provides a direct mountfor the swingarm. Another castingattached to the rear of the lowercase provides a solid mount for the VFR’s footpeg gear, side andcentre stands, and the pivot arm forthe suspension’s progressive Delta-Link, all of which would normallybe attached to the lower portion ofthe frame in a conventional design.
9
VFR
Engine
Swingarm Assembly Cross-Section
Cylinder Head Comparison (Cross-Section)! New VFR@ Current Model
Cylinder Head Comparison
!
@
VFR
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New Metal Composite Cylinder SleevesThe VFR’s engine also features newmetal composite cylinder sleeves likethose used in the RVF/RC45 that areat least 2kg lighter than their steelcounterparts. Formed of sinteredaluminium powder impregnated withceramic and graphite, these advancedsleeves also offer exceptional durabil-ity, while transmitting heat more
effectively than conventional steelsleeves. The three-ring pistonsthemselves feature a ‘slipper’ designthat minimizes sidewall surface areacontact for reduced frictional losses,and a new LUB-Coat solid lubricantcoating that minimizes the potentialfor piston and sleeve surface scorch-ing, while further cutting down onpower-robbing friction.
10
VFR
Engine
VFR
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Computer-Controlled ProgrammedFuel Injection (PGM-FI)The VFR’s computer-controlledProgrammed Fuel Injection (PGM-FI) system is based on thesystem developed, like its engine,for Honda’s RC45 Superbike racer.
Featuring a simplified design thatuses fewer parts, this new systemprovides ultra-precise fuel meteringfor optimal performance over awide range of operating conditionsand the lowest possible emissions.The four injector throttle bodies feature large 36mm bores to ensureoptimal airflow.
11
VFR
Engine
PGM-FI Fuel Injection System Comparison
PGM-FI Fuel Injection SystemComparison! Component@ Electronic Control Unit# Independent Cylinder Mapping$ New VFR% Intake Pressure Map^ Throttle Position Map& Ignition Timing Map* RVF (RC45)( Front CylindersBL All CylindersBM Rear CylindersBN Igniter
!#
@
!
$
*
% ^ &
( (
@
BL
BM BM
BN
VFR
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The system’s Electronic ControlUnit (ECU) is also integrated withthe VFR’s new map-type electronicignition into a single compact unit,and even the ACG output wasincreased from 364W to 463W toensure strong, reliable operation.
The intake system’s large-volumeaircleaner features a newly developed dual air intake ductthat optimizes the flow of air intothe aircleaner by using a solenoidto keep one of the ducts closedduring low-speed operation and only
opening it as speeds—and the needfor larger volumes of air—increase. An electronic fuel pump is built intothe large, 21-litre fuel tank to ensurea steady flow of fuel to the injectors.
12
VFR
Engine
Fuel Injector Comparison
PGM-FI System! Air intake duct control@ Intake air temperature sensor# Injection control$ Intake manifold pressure sensor% Fuel pump control^ 12V power supply& Barometric pressure sensor* Battery( Camshaft pulsarBL Throttle SensorBM Crankshaft pulsarBN Coolant temperature sensorBO ECU
PGM-FI System
PGM-FI Fuel Injection Programming Maps
Fuel Injector Comparison! RC45@ New VFR
!@
PGM-FI Fuel Injection Programming Maps! Intake Manifold Pressure@ Injection Interval# Engine Speed (rpm)$ Throttle Position
!
@
#
$
#
@
!
@
#
$
%
^
&*
(
BL
BM
BO
BN
! @
VFR
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Low-Emissions Air Injection SystemSimilar in concept to systems recently introduced in severalHonda on-road machines, the VFR features a new solenoid-controlled air injection systemthat shoots a stream of fresh airinto each exhaust port during its exhaust stroke to extend thecombustion of unburned gases
into the exhaust port for morecomplete combustion and reduced exhaust emissions.
These cleaner burning exhaust gasesempty into a 4-into-2-into-1 exhaustsystem that terminates in a large 6.5-litre stainless steel canister-stylesilencer like the two mounted on the CBR1100XX Super Blackbird.
This system is further expandedupon in the low-emissions version of the VFR, which features an in-novative new Honda EvolutionalCatalyzing System (HECS3) thatwas specially developed for releasein Germany and Switzerland (refer to attached article).
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VFR
Engine
Exhaust Silencer Cross-Section
VFR
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High-Efficiency Dual Radiator Cooling SystemOne of the VFR’s most interestingnew features is its new dual-radia-tor cooling system. Turning awayfrom the conventional single radia-tor that has till now been mountedbehind the front wheel, the newVFR features two radiators moun-ted on either side of the front of the
engine, much like the system intro-duced on this year’s VTR1000F.This new positioning offers severalunique design advantages. First, thearea behind the front wheel is freedof a major obstruction in air flow,permitting a steady stream of coolingair to better reach the front and rearcylinder banks and the exhaust system. The same lack of a space-
consuming radiator here also pro-vides more freedom in determiningthe best placement of the morecompact engine and the optimalwheelbase length, since the frontwheel can now be positioned closer to the engine. Likewise, front cylinder maintenance is also made infinitely easier.
14
VFR
Engine
VFR
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The designs of the fairing’s sidecowls also play an integral part inthe air flow through the radiatorsand their subsequent cooling capac-ity. At speed, the air flowing acrossthe fairing’s large radiator ports cre-ates low pressure zones that literallypull air through the radiators fromthe higher pressure cavity behindthe front wheel.
To illustrate the effectiveness of thisdesign, removing the cowls wouldcause air of the same relative pres-
sure to rush over both surfaces of theradiator cores rather than throughthem, resulting in a drastic reductionin their cooling capability.
A large, thermostat-activated fan is mounted on the inside surface ofthe left-side radiator to ensure thatthe radiator is able to do its job ifengine temperatures should everrise at low operating speeds, suchas those experienced in stop-and-gocity traffic. In such cases, the fanautomatically switches on to pull
cool air directly in from the sideand into the fairing cavity, awayfrom the rider.
Further ensuring optimal coolingefficiency, the VFR also features a compact oil cooler mountedunder the steering head, where itspositioning immediately above andbehind the front wheel permits it to catch a direct, unimpeded blastof cooling air.
15
VFR
Engine
VFR
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New ‘Pivotless’ Twin-Spar FrameFollowing in the development path pioneered by the VTR1000F,the new VFR features an all-new‘pivotless’ frame that achieves theultimate in simplicity, strength andlight weight by eliminating a funda-mental area of stress and weight in conventional frame designs: theswingarm pivot plates. Rather thanbeing mounted to these plates in aconventional frame configuration,the swingarm is mounted directly to the new, specially designed pivot
castings at the back of the enginecases. By eliminating the need forthe frame’s pivot plates and conven-tional downtubes, the new frameachieves a weight loss of fully 3.5kgcompared to the already lightweightframe used in the current VFR750F,yet it maintains the same high degree of strength and rigidity.
This ultra-lightweight new ‘pivotless’frame is constructed of massivetriple-box-section aluminium sparswith welded-on cast engine hanger
plates that anchor the cast steeringhead directly to the engine. At therear, they merge into a large centralcasting that surrounds the rear cy-linder head and provides a solidmount for the top-end of the reardamper and the bolt-on seat rail.Up front, the steering head’s casterangle combines with the enhancedengine positioning made possibleby the new side-mounted radiatorsto provide a shorter wheelbase forlighter, sportier handling and excel-lent straight-line stability.
16
VFR
Chassis
Frame Spar Cross-Section Comparison
Frame SparCross-Section Comparison! New VFR@ Current Model
Frame ConfigurationRear Suspension Mounting Bracket
Frame Configuration! New VFR@ Current Model
Rear Suspension Mounting Bracket! Delta-Link@ Sidestand# Anchor arm$ Centrestand
! @!
@
!
@
$
#
VFR
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Crankcase-Mounted Pro-Arm; Advanced Delta-Link Rear SuspensionThe central point of focus for theVFR’s rear suspension and onehighlight that consistently standsout from other motorcycles is without a doubt its large yet lightweight single-sided castaluminium Pro-Arm swingarm.Rigid and reliable, it provides a solid mount for the rear sprocket
and disc brake assembly whilepermitting remarkably fast rearwheel changes by way of four easy to remove bolts. Since the new VFR’s Pro-Arm is nowmounted directly to the rear of the engine, its enhanced lateralrigidity and isolation from theframe virtually eliminates the rear wheel’s torsional stress on theframe and its effects on handling.
The swingarm’s proven Pro-Linksuspension system provides 120mmof progressive axle travel and is sup-ported by a 40mm H.M.A.S. damperthat offers adjustable spring preloadand rebound damping. The system’sDelta-Link is anchored, by way ofan extension arm, directly to the castaluminium bracket mounted on therear of the lower engine case.
17
VFR
Chassis
Ratio Curve
Pro-Arm
Ratio Curve! New VFR@ Current Model# Ratio $ Axle Stroke
!
@
$
#
VFR
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H.M.A.S. Cartridge-Type Front ForkThe VFR’s rigid and responsive41mm cartridge-type front fork features Honda’s H.M.A.S. designfor a confident balance of precisehandling and compliant damping.Gripped at the top by aluminiumclip-on handlebars and an elegantcast aluminium upper triple-clamp,these forks offer stepless spring preload adjustment and 120mm of smooth, progressive operation.
Lightweight Wheels; Radial TyresThe VFR rolls on lightweight, U-section cast aluminium wheelsthat project a modern image ofstrength and speed. The prominentside-mounted 5-spoke rear wheelfeatures a sharp, new angular, high-tech design and a wider 5.5" rim to mount a wider body radial tyre.Its smaller, lighter damper insertsreliably absorb the shocks of suddenacceleration and downshifts.
Designed especially for high speedscoupled with responsive handling, the new VFR mounts a set of high-performance wide-profile radial tyres.
18
VFR
Chassis
Suspension Damping Characteristics Comparison
Suspension Damping Characteristics Comparison! Front@ Rear# New VFR$ Current Model% Rebound^ Compression& Velocity
! @
$#
^
%
%
^&
&
VFR
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Compact Three-Piston CalipersLike the system used on theCBR1100XX, the VFR’s CBSfeatures a set of three compactthree-piston calipers controlled bytwo independent hydraulic systems.Differing slightly from the CBR isthe arrangement of brake pistonactuation. On the new VFR, thetwo outer pistons of the front
calipers are controlled directly by the hand brake lever, and thecentre piston of the rear caliper iscontrolled by the secondary mastercylinder mounted on the left frontfork bottom case. The outer pistonsof the rear brake caliper and thecentre pistons of the front calipersare directly operated by the footbrake pedal.
19
VFR
Dual Combined Brake System
First introduced on the 1993 CBR1000F and having undergone several stages ofdevelopment on the 1996 ST1100 Pan-European CBS-ABS with TCS and thisyear’s CBR1100XX Super Blackbird, Honda’s innovative Dual Combined BrakeSystem (Dual CBS) simultaneously engages both front and rear brakes wheneither the front brake lever or rear brake pedal is used. Although incorporatingmany of the same components as the system used on the CBR1100XX, this latestevolution of the Dual CBS was further refined and tuned for a superb balance of Super Sport braking characteristics and a more ‘combined’ feel that will appealto a wide range of riders. Foot brake settings have also been fine-tuned to offer a more conventional feel of braking control that combines strong and stablestopping power and smooth, sporty cornering performance.
VFR
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Brake Force-Actuated ServomechanismMuch like the simplified system fea-tured on the CBR1100XX, when the front brake is engaged, the CBS’sservomechanism uses the rotationaltorque exerted on the front calipersto pull the left-side caliper’s torquearm bracket forward to directly ac-tuate the secondary master cylinder.
Entirely new to the VFR’s system,however, is that the secondary mas-ter cylinder is now an integral partof the torque arm casting, with its
piston attached directly to a mountbuilt into the left fork bottom case.The forward movement of the torquearm causes the secondary mastercylinder to apply a correspondingamount of pressure to the centrepiston of the rear brake caliper. An inline proportional control valve(PCV) regulates this brake pressurein three stages of operation to en-sure smoothly controlled response.Depending on which brake lever isengaged, this system delivers a wide,easily controlled range of braking
force while offering the same frontbrake lever feel as a conventionalbrake system, yet with a more pro-gressive range of rear brake controlfor an enhanced balance of brakingcapability. Because the two hydraulicsystems are independent, any combi-ation of the foot pedal and the handlever can be used without resulting in excessive braking force or otherunusual responses.
20
VFR
Dual Combined Brake System
New Compact Dual Combined Brake System
New Compact Dual Combined Brake System! Hand brake master cylinder@ Delay valve# Right front caliper$ Lever actuation% Left front caliper^ Pedal actuation& Foot brake master cylinder* Rear caliper
!
@
#
$
%
^&
*
VFR
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Delay Valve for Smoother OperationThe system’s integral delay valvesmoothes front brake engagementto minimize front-end dive whenusing the foot brake to make minorspeed corrections. Positioned be-tween the foot brake’s master cylin-der and the centre pistons of thetwo front brake calipers, the delayvalve first engages only the left-sidefront caliper to reduce the initialfront wheel braking force by nearlyhalf. As pedal pressure increases,the delay valve introduces pressure
to the right-side front caliper, whichrises from a preset level to matchthe pressure to the left-side caliper.The result is a feel of comfortable,even deceleration that begins at therear, with little of the rapid forwarddive that is usually brought on whenthe front brakes are suddenly applied.The delay valve offers enhancedcontrol and more confident ease of operation over irregular road surfaces, such as slippery downhillgrades and wet cobblestone roads.
Floating Brake RotorsThe VFR’s 296 × 4.5mm floatingfront discs feature lightweight ‘7-star’ aluminium inner rotors anda reduced number of floating diskinserts (down from the standard 10 or 12) to provide a lighter, more open look. The rear discbrake features a standard, single-piece 256mm rotor. A new sinteredmetal front brake pad material pro-vides sportier braking performancewhile optimizing the balance offront and rear braking control.
21
VFR
Dual Combined Brake System
VFR
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Dual Multi-Reflector HeadlightThe VFR’s wide, integrated dualheadlight features the latest in multi-reflector headlight design for clearlydefined nighttime illumination andenhanced riding confidence. The headlight’s brilliant output isdetermined by the computer-design-ed shapes of its angular reflectors,which precisely focus their beams in an optimized illumination patternwithout requiring a conventional
headlight’s thick faceted lens to bendthe beam to fit. Both bulbs are nowilluminated during both low beamand high beam operation. The head-light’s clear, flush-surface ‘cat-eyes’lens was specially molded to con-form to the upper fairing’s leadingedge, while a regulation positionlamp is mounted in the front bot-tom centre of the headlight unit.The VFR’s large, newly designedfront indicators feature greater
transparency than standard unitsand are prominently mounted onthe fairing shroud for maximumvisibility. Its attractively designedtaillight juts out from the end ofthe tail cowl in a broad, cleanlyrounded form that integrates bothrear indicators into its shapelydesign to provide a bright, high-visibility view from the rear.
22
VFR
Equipment
Current Model Headlight Illumination Area Comparison (Overhead V iew)
New VFR Headlight Illumination Area Comparison (Overhead V iew)
New VFR Headlight Illumination Area Comparison (Overhead V iew)! High Beam@ Low Beam
Current Model Headlight Illumination Area Comparison (Overhead V iew)! High Beam@ Low Beam
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!
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VFR
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High-Tech Meter PanelThe VFR’s sleek, fairing-integratedmeter panel provides an attractive,high-tech display of important operating information in the no-non-sense style of a jet fighter cockpit. With its large, black-face speedome-ter mounted to the left of the large,centrally positioned white-face tacho-meter, and indicator light arrayedacross the bottom of the panel, theslim new, fully electronic panel fea-tures a large, high-visibility liquidcrystal display of fuel level, coolanttemperature, clock, odometer andtrip meter readings. The handy dual-mode trip meter permits twodifferent distances to be indepen-dently measured.
Solid Aluminium ComponentsThe VFR has always projected apowerful, mechanical, high-techlook that exudes the highest qualityin its attention to detail and the fit and finish of its componentry.Its impressive array of cast orforged aluminium parts includenew aluminium brake pedal andshift lever pieces that replace thesteel components mounted on thecurrent model.
• The VFR’s large-capacity 21-litrefuel tank provides an extended rangeof touring enjoyment between fillupsand features a built-in electronic fuel pump to ensure a reliable flow of fuel to its new electronicfuel injection system.
• The VFR’s detachable rear seatoffers access to a compact storagespace that can carry a ‘U’-lock andother small necessities.
• Clutch and brake levers offereasy 4-position adjustment to com-fortably fit a wide range of hands.
23
VFR
Equipment
HECS
3 - 9
824
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24
HECS
3 - 9
825
- E
Honda has long been concernedwith reducing pollution levels in the products it makes and has beena pioneer in the development oflow-emissions engines and vehiclesthat still produce exceptionally highlevels of performance. However,rather than settling for added-ondevices that focus on the symptomsbut often ultimately compromise
other aspects of engine performance,Honda has always strived to findsolutions to these problems at theirsource by thoroughly rethinking thefundamentals of combustion. Takingadvantage of Honda’s recently de-veloped built-in air injection systemand the precise fuel metering capa-bility of its PGM-FI programmedfuel injection system, this advanced
new emissions system incorporatesoxygen sensors and a ‘3-way’ cata-lytic converter to maintain peakcombustion efficiency while redu-cing emissions to far below thosecalled for by Europe’s expected newregulations and likewise ensuringthe highest long-term reliability.
25
As the world grows more concerned about the effects of pollutants on the environ-ment, many developed countries have instituted steadily stricter regulations tocombat rising pollution levels, especially as they affect our water and the air webreath. Scheduled to take effect in 2001, Europe’s planned EURO-2 emissions reg-ulations are expected to be some of the strictest air pollution controls on recordand will no doubt become a point of reference for pollution laws that may be intro-duced in other countries in the future. Though not yet finalized, its proposed limitson emissions of carbon monoxide (CO), hydrocarbons (HC) and nitrous oxides(NOx) are expected to closely approximate Germany’s pending Summer SmogStage II regulations, and will be so strict that only catalytic converter-equippedvehicles will be permitted to operate in countries adopting the new regulations.Although these strict new regulations do not currently affect motorcycles and aredirected mainly towards passenger cars, similar regulations concerning the emis-sions of motorcycles and other small engines can be expected to follow.
HECS3
Introduction
HECS
3 - 9
826
- E
Digital Fuel Injection SystemEssentially the same digital elec-tronic system featured on several of Honda’s standard models, thePGM-FI system’s programmed ECU ensures precisely controlleddelivery of the optimal amount of fuel required for all starting and riding conditions.
Air Injection SystemBased on the direct air injectionsystem used on several currentmodels in the Honda lineup, thisnew solenoid-controlled systemintroduces a stream of fresh airfrom the aircleaner into the exhaustport just behind the exhaust valve.By delivering extra oxygen to theexhaust gases exiting the combus-tion chamber, the system prolongsthe burning of the exhaust’s resi-
dual fuel into the port for morecomplete combustion and reducedemissions of carbon monoxide andhydrocarbons. The volume of airinjected into the port is determinedby the velocity of the gases exitingthe combustion chamber. This simple system reduces carbonmonoxide and hydrocarbon emissi-ons to ensure complete compliancewith Europe’s current EURO-1 emissions regulations.
26
HECS3
System Components
This high-performance emissions system combines Honda’s built-in air injectionsystem, an advanced digital electronic fuel injection system with oxygen sensorsto monitor exhaust composition, and a 3-way catalytic converter to minimizeemission levels while maintaining high performance and long-term reliability.The major components of the system are:
HECS 3 Honda Evolutional Catalyzing System
HECS 3 Honda Evolutional Catalyzing System! Ambient Air Pressure@ Barometric Pressure Sensor# Fuel$ Air Intake% Air Flow^ Intake Air Temperature Sensor& Aircleaner Box* Fuel Flow( PGM-FI/Ignition UnitBL Sensor InputsBM PGM-FI OutputsBN Exhaust FlowBO Solenoid ValveBP InjectorBQ Throttle SensorBR Intake Manifold Pressure SensorBS O2 SensorBT Metal CatalyzerBU Coolant Temperature SensorCL Cleaner Exhaust Gas
!
@
#
$
%^
&
*
(
BLBM
BNBO
BPBQ
BR BS
BT
BU
BT CL
BP
HECS
3 - 9
827
- E
Stainless Steel Exhaust SystemThe stainless steel exhaust systemfeatures narrower diameter tubingthan that used on the standard model. This specially designedsystem combines with the air injection system to quickly raise the temperature of the catalyticconverter elements for optimaloperation. The catalyzer is installedjust behind the final exhaust pipejunction in the system’s 4-into-2-into-1 configuration, and feeds into the single tube extending to
the system’s silencer. This modifiedsystem ensures that the catalyzer’stemperature quickly reaches itsoptimum level of over 300˚C, andstably maintains the catalyzer withinthis most effective temperature range.
Electronic Exhaust SensorsA pair of electronic sensors are in-stalled immediately behind the firsttwo junctions of the exhaust pipes(in the above-noted 4-into-2-into-1sytem), where they constantlymeasure the fluctuating oxygen
levels in the engine’s exhaust gases.Their digital output is monitoredby the fuel injection system’s CPU,which instantly calculates combus-tion efficiency and corrects the in-take’s air/fuel mixture accordingly.This ‘O2 feedback’ system maintainsthe air/fuel mixture within a pre-designated tolerance range that iscentred on the optimal ratio for the most efficient combustion.
27
HECS3
System Components
HECS
3 - 9
828
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This optimal 14.7:1 air/fuel ratio is determined by a precise balancebetween the resulting emissions of hydrocarbons (HC) and carbonmonoxide (CO) on one hand andnitrous oxides (NOx) on the other.If this ratio increases, HC and COoutput will fall, but NOx emissionswill rise correspondingly.Conversely, if the air-to-fuel ratiofalls below this figure, NOX outputwill be reduced, but HC and COemissions will quickly rise. Thus,to achieve the most effective andefficient low-emissions operation, a precise balance of minimal emis-sions for all three pollutants mustbe maintained.
Constantly monitoring exhaustoutput for the ideal 14.7:1 air/fuelratio, the ‘O2 feedback’ systemminutely modulates the amount offuel passing through the injectors,enrichening the mixture when themeasured ratio climbs too high and leaning it out slightly when theratio falls too low. In this way peakcombustion efficiency is preciselymaintained through a wide range of operating conditions.The sensors themselves are standardautomotive- type Isolated GroundHeated Zirconia Exhaust GasOxygen Sensors.
‘3-Way’ CatalyzerThe final component in the low-emissions system is the catalyzerunit installed in the exhaust systemimmediately after the final 2-into-1junction. This compact unit contains a dual oval ‘3-way’catalytic converter element thatcompletes the system’s operation by minimizing the emissions of CO, HC and NOx.
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HECS3
System Components
Catalyzer Dimensions
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Exhaust System Comparison(showing catalyzer placement)
Exhaust System Comparison! Side view@ Top view
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VFR
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Specifications
Specifications VFR (ED-type)
Engine Liquid-cooled 4-stroke 16-valve DOHC 90° V-4Bore × Stroke 72 × 48mmDisplacement 781cm3
Compression Ratio 11.6 : 1Carburation Electronic direct fuel injectionMax. Power Output 106PS/10,500rpm (95/1/EC) (78kW/10,500min-1)
110PS/10,500rpm (DIN) (81kW/10,500min-1)Max. Torque 8.1kg-m/8,500rpm (95/1/EC) (79Nm/8,500min-1)
8.4kg-m/8,500rpm (DIN) (82Nm/8,500min-1)Ignition Computer-controlled digital transistorized with electronic advanceStarter ElectricTransmission 6-speedFinal Drive ‘O’-ring sealed chainDimensions (L×W×H) 2,095 × 735 × 1,190mmWheelbase 1,440mmSeat Height 805mmGround Clearance 130mmFuel Capacity 21 litresWheels Front 17 × MT3.50 ‘U’-section 6-spoke cast aluminium
Rear 17 × MT5.50 ‘U’-section 5-spoke cast aluminiumTyres Front 120/70 ZR17 (58W)
Rear 180/55 ZR17 (73W)Suspension Front 41mm H.M.A.S. cartridge-type telescopic fork with stepless preload
adjustment, 120mm axle travelRear Pro-Link with 7-step preload and stepless rebound-adjustable
gas-charged H.M.A.S. damper, 120mm axle travelBrakes Front 296 × 4.5mm dual discs with Combined 3-piston calipers and sintered
metal padsRear 256 × 6mm disc with Combined 3-piston caliper and sintered metal pads
Dry Weight 208kg
All specifications are provisional and subject to change without notice.