Supersport flagship reborn with newhigh-performance engine and Deltabox V (Victory) frame New 2004 European market model Yamaha Sports "YZF-R1" debuts at Milano Show

Yamaha Motor Co., Ltd. (YMC) announces the debut of the new remake of the Yamaha Sports “YZF-R1” in its 2004 European market model at the 60th Milano Show (bicycles and motorcycles) opening on September 16 2003.

After its debut at the Milan show in September of 1997 (as a 1998 model), the original YZF-R1 quickly won unprecedented acclaim as a model that offers “full enjoyment riding a 1000cc machine” and also as “the super cornering machine” instantly set a new standard for the supersport category. Since then, with its first minor model change in 2000 and a further evolution in 2002 that added a new frame and fuel injection among other features, the YZF-R1 has continued to lead the supersport market.

The new 2004 YZF-R1 maintains the same model concept that has held consistent from the first-generation (1998), second (2000) and third-generation (2002) models while adding the latest Yamaha technologies to achieve an outstanding balance of (1) styling, (2) performance and (3) the kind of agile cornering performance to make it a “beautiful, exciting sports machine that wins the title of fastest in secondary road riding.” The result is a model that takes the 1000cc supersport category into an entirely new dimension.

2004 European market model Yamaha Sports “YZF-R1”

Demand in the European supersport market has held steady in recent years at an annual level of 150,000 units. This market can be divided roughly into the 600cc class and the over 750cc class. This over 750cc class (= 1000cc models) has been the center of increasing attention since the change in the World Superbike regulations that allows entry of 4-cylinder 1000cc models beginning with the 2003 season.

To this 1000cc class, the various makers have introduced many new models, but the Yamaha YZF-R1, as it has continued to mature from the first-generation model through the second (2000) and third-generation (2002) models, continues to maintain strong user following and influential position as a symbol of the 1000cc supersport bike. The reasons that most people give for this continued popularity is the R1’s innovative styling and its great cornering performance.

Meanwhile, user needs have continued to diversify in recent years with different customer groups looking for (1) performance and function, (2) utility and (3) styling.
Considering these customer trends, the product concept for the new YZF-R1 was to further develop the existing model’s already outstanding cornering capabilities while adding a new dimension of performance to make this an exciting new supersport model. The development concept was defined as a “beautiful, exciting sports machine that wins the title of fastest in secondary road riding.” By adopting design ideas from the MotoGP machine YZR-M1 and the latest technologies available throughout the design the idea was to build a model that had a great balance of the three elements of “cornering,” “performance” and “styling.” The result is a machine character defined by,“unmatched power in secondary road riding and the performance to let you handle it at will.”

1) New-design big bore, lightweight engine
In order to achieve high-level performance and cornering potential, the new YZF-R1 adopts a newly designed power unit. The heart of this unit is the liquid-cooled, 4-stroke DOHC, 40-degree forward-inclined, in-line-4-cylinder, 5-valve, fuel injection-equipped engine designed especially with optimum intake-exhaust efficiency in mind.
Compared to the existing YZF-R1’s this new engine has been bored out another 3mm and given a bore x stroke of 77.0 x 53.6mm (74.0 x 58.0 for existing model), optimized throat diameter, a new compact combustion chamber, forged aluminum pistons, high-lift cams and a high compression ratio of 12.3 : 1, from which its delivers a maximum power output of 172 PS/12,500 rpm (when not including forced-air intake). Furthermore, thorough weight reducing measures throughout the engine have made it approximately 4 kg lighter (engine alone). In combination with the close-ratio 6-speed transmission, this delivers performance truly worthy of being called “No.1 in Performance.”

2) Closed deck type cylinder for higher compression ratio
In order to achieve a higher compression ratio and power output, a closed deck type cylinder is adopted. By casting the cylinder block with a unique Yamaha low-pressure aluminum casting method to ensure maximum metallurgic strength, it was possible to make a highly effective closed deck type cylinder characterized by the fact that the coolant passages do not go through the head portion, thus enabling a more rigid structure. Ensures excellent reliability to accommodate the high compression ratio, high output cylinder. And, thanks to design efforts to reduce the cylinder pitch as much as possible, the lateral width of the cylinder is only 4mm wider than the existing model despite the increased bore.
Furthermore, a direct plated liner-less cylinder (ceramic composite plating) format has been adopted to ensure outstanding heat dissipation characteristics, improved rigidity balance and the capacity for a more accurate cylinder shape.

3) FS conrods adopted for outstanding reliability
To ensure conrod reliability in light of the increased power output, so-called FS conrods (Fracture Splitting Connecting Rod) are adopted for the large end of the connecting rods for the first time ever on a Yamaha motorcycle (machined conrods have been used until now). In this method, the large end of the rod is machined into a cylindrical shape and then shock-split. When assembling, the matching split surfaces are rejoined and bolted together to form a highly precise cylindrical form again which contributes to outstanding reliability in high-rpm use. (FS conrods = Fracture Splitting Connecting Rods)

4) Fuel injection and sub-throttle for ease of use in low- to mid-speed range
In order to obtain outstanding performance while also improving the engine’s environment-friendliness, this model adopts a fuel injection (FI) system. The injector is a highly reliable plate type, long nozzle unit with two-direction, four-outlet design for outstanding dynamics range.
And, what makes the YZF-R1 system unique is the adoption of a motor-operated sub-throttle valve controlled on the basis of information about engine rpm and the throttle opening fed back via the ECU in order to provide excellent power control characteristics. The functioning of the main and sub throttle valves enables optimum control of the intake air flow speed. This enables optimized volume efficiency across the entire rpm range, thus resulting in the kind of outstanding low- to mid-speed drivability only digital control can provide.
A link mechanism has also been added to the butterfly action in order to achieve a more compact design that results in a throttle body that is 27mm slimmer in lateral width than the existing YZF-R1. This slimmer throttle body has in turn allowed greater freedom in the design of the new high-rigidity frame that contributes to this model's outstanding handling characteristics.

5) Air induction contributes to excellent response characteristics
An air induction system is adopted to increase intake efficiency by utilizing the natural air flow during riding to pressurize the air in the air box. In this system, two intake ducts located below the headlights channel air to the dirty side of the air cleaner positioned in front of the fuel tank. From there it passes through the filter and is then pressurized on the large-capacity clean side. The induction and pressurizing of this cool air supply is an important factor in improving power development and giving the new YZF-R1 its outstanding response during acceleration.

6) Compact design EXUP connecting two cylinders each
Yamaha’s EXUP system that functions to eliminate torque valleys and provide excellent power development characteristics has been made more compact on this model while retaining the same basic operating principle. Unlike the former system that included a separate valve for each of the four exhaust pipes, the system on the new YZF-R1 places just two EXUP valves at the points where the four exhaust pipes merge into two, thus creating a more compact system that controls the pulse based on calculations of the 1st and 2nd cylinders’ exhaust and the 3rd and 4th cylinders’ exhaust. The material used in the new valves has also been changed, from SUS to titanium. With the bodies also made of titanium, this now makes them all-titanium units.

7) Up-muffler design for excellent exhaust efficiency and distinctive look
An up-slanting muffler has been adopted that gives a highly impressive look to the exterior. The exhaust system is designed with optimum pipe lengths, silencer expansion chamber and sizes of the different pipes so as not only to bring out the performance of the new engine in the most efficient way but also to create a boldly impressive accent to the machine’s styling.

8) Other engine-related features
Other features include (1) a forged aluminum retainer to accommodate the higher revving engine, (2) an optimized flywheel mass setting (20% lower than the existing YZF-R1) that provides thrilling acceleration feeling, (3) a round type radiator for excellent cooling performance and (4) an ACM (Alternating Current Magneto) positioned at the rear surface of the crankcase to ensure a deep banking angle and a low engine center of gravity.

1) New Deltabox V (Victory) frame with 2.5 times greater rigidity
The new YZF-R1 adopts a newly designed frame we call the Deltabox V (Victory). Incorporating design aspects of the frame of our YZR-M1 and 3D CAD analysis, this new frame has been given a high level of rigidity to make it fully viable for circuit riding and stock class racing. With this aim in mind, the main frame was designed narrow in the lateral direction and the head pipe and pivot connected more directly in a straight line.
For the outside portions of the main frame high-elasticity panel stock has been used, while high-strength cast parts are used for the inside and the two welded together to create box sections for a highly reliable hollow-type frame structure. Also, the use of optimum types of aluminum stock in the various parts, like cast parts for the pivot assembly, and the right thickness of stock have contributed to the good overall rigidity balance. As a result, the rigidity values compared to the existing YZF-R1 have been increased 2.5 times for longitudinal rigidity and 1.3 times for lateral and torsion rigidity.

2) Optimized engine mounting position and weight distribution for excellent initial-stage steering characteristics
In order to achieve high-level steering performance, especially in the initial stage, the engine mounting position, front-rear weight balance and cylinder forward incline angle (angle increased from 35 to 40 degrees) have been optimized in relation to each other in terms of position and balance. Compared to the existing model the engine center of gravity has been lowered and moved toward the front wheel. This combines with the effect of optimized dimensions like a 5mm increase in the fork offset to 30mm to help achieve stable handling that lets the rider enjoy quicker response characteristics in initial-stage steering action.

3) High-performance front and rear suspensions and rear arm with upside-down truss configuration
In the front suspension, the upside-down fork with 43mm diameter tubes provides both excellent cushioning and quick handling characteristics. And, the rear liked-type suspension adopts an aluminum rear arm with an upside-down truss configuration to balance the positioning with the new up-muffler. This provides excellent rigidity balance and cushioning performance. Also, the rear suspension’s preload adjuster is now made of aluminum for added quality look. The rear frame is constructed of parts made by Yamaha’s CF aluminum die-cast method that boosts welding characteristics and aluminum sheet metal to create a box structure that gives greater rigidity while also contributing to a higher quality aluminum look to the exterior.

4) Front brake with radial-mount caliper
A new brake system has been developed to match the machine’s increased performance dynamics and provide outstanding functionality and control characteristics. The front brake features a 320mm diameter disc and radial type pump that enables a larger lever action for the master cylinder and excellent control characteristics. The caliper is given a radial mount that minimizes distortion induced by the reactive force during braking. These factors combine to help ensure stable braking power and control especially during hard braking. This radial type mount is also characterized by excellent response during brake release that enables well-modulated braking action. The rear brake adopts a 220mm diameter disc for excellent braking function and control characteristics.

5) Fuel tank with separate cleaner and tank sections
Replacing the old design where the fuel tank enveloped the air cleaner box, the new design is characterized by the fact that the cleaner is moved forward and completely separated from the new slimmer tank (50mm slimmer in left-right width than the existing model). Combining with the slimmer frame design, this gives excellent knee grip characteristics.
Also, while the seat is thinner at the tank end, in the middle portion, which is the critical part during weight shifting, a sufficient surface area has been provided to ensure good machine hold for the rider. The handlebar and footrest position have also been changed to match the new engine character.

6) Bold new 2-facet body design
The body design of the new YZF-R1 is defined by new front view and rear view, each of which features a 2-facet design. With its new 4-lamp headlight design, the front view has an expression that exudes pure power. At the same time, the air ducts are designed to give the impression of drawing in large volumes of air. On the other hand, here are also lines that stress sleek aerodynamics, expressed in the sense of flow of the air from the leading edge of the upper cowl smoothly back along the body and directly into the intake.
As for the tail assembly, the up-muffler gives an expression of performance, while the combination of the muffler and the tail cowl in their integrated design also express aerodynamics. Meanwhile, the muffler itself is designed to create an image of the power flow from intake to combustion and exhaust. What's more, the compactness of the muffler layout helps give an impression of the flow of air around the tail that is a new accent point of the YZF-R1.

7) Other Features
Other features include (1) new lightweight 5-spoke wheels with optimized rigidity balance between the hubs and rims, (2) new-design meter panel with the tachometer to the center (a liquid-crystal speedometer and clock on the left and the liquid-crystal tripmeter on the right), (3) a two-lamp, 4-bulb headlight design and super-lightweight cowling that accentuate the renewed styling of the YZF-R1, (4) LED tail lamp and (5) a single-unit lightweight die-cast rear frame designed to match the up-muffler layout.