HARDRIDER MOTORCYCLE SUMMER 2021 (Quarterly)

Suzuki lightly revised the GSX1300R for the 2008 model year, with a minor restyling of the bodywork, and fine- tuning of the engine’s head, pistons and exhaust. Though the engine changes were relatively limited, they still yielded a large horsepower increase, and brought the bike into compliance with new noise and emissions requirements. In 2004, market researchers from the US and Japan began working to identify which elements of the Hayabusa design had attracted so many buyers, discovering that, in spite of having its looks sometimes disparaged in print, customers were much enamored with the old Hayabusa. A redesign meant to strengthen the bike’s appearance without departing much from the original found approval with dealers and focus groups. Underneath the skin, Suzuki decided to save considerable development cost by keeping major portions of the frame and engine unchanged. This was because engineers had determined greater power was possible without a significant redesign of the old engine, even faced with the need to comply with more stringent noise and air pollution rules. The target was to produce more than 190 bhp (142 kW) at the crankshaft, and they delivered 194 hp (145 kW), a 11 or 12 percent increase over the previous output. Yoshiura’s new design aimed to complement the rider’s muscular structure, in part based on meetings with riders of customized Hayabusas. Suzuki’s Koji Yoshiura designed the look of the new Hayabusa. He had previously styled the first generation Hayabusa, as well as the Suzuki Bandit 400, RF600R, TL1000S and the SV650. For research, Yoshiura traveled around the United States to bike nights and clubs for a first hand look at the styling aesthetic of the Hayabusa custom scene, and was inspired as much by the look and build of the Hayabusa rider as their custom bikes. While the second generation is very close to the first in overall shape, and is largely dictated by wind tunnel tests, the raised lines and curves are meant to suggest a muscular build. Said Yoshiura, “I wanted to create a masculine form that complements a rider’s muscular structure with hints of developed bicep, forearm and calves.” Engine changes consisted of an increase in stroke by 2 mm, enlarging displacement to 1,340 cc (82 cu in). The compression ratio was boosted from 11:1 to 12.5:1 and the cylinder head was made more compact and was given lighter titanium valves, saving 14.1 g (0.50 oz) and 11.7 g (0.41 oz) on each intake and exhaust valve, respectively. The valves were driven by a chain with a new hydraulic tensioner. The pistons were made lighter by 1.4 g (0.049 oz)[41] and used ion-coated rings and shot peened connecting rods. The crankcase breather system had reed valves added to control pressure waves in the intake airbox, a way of avoiding power loss. Fuel injectors from the GSX-R1000 were used, with smaller 44-millimetre (2 in) throttle bodies, called the Suzuki Dual Throttle Valve (SDTV) system. It has three selectable options of power delivery for a range of touring to wide open high performance. The exhaust system was overhauled, using a 4-2-1- 2 system, meaning four exhaust outlets merging into two pipes, and then joining into a single pipe before splitting into two enlarged, quieter mufflers, which added a few pounds of weight compared to the first generation Hayabusa. The exhaust also included a catalytic converter and an oxygen sensor in order to meet Euro 3 emissions requirements. The suspension was upgraded with a 43 mm Kayaba inverted fork with sliders having a diamond-like carbon (DLC) coating. The rear shock is also a Kayaba, and the overall suspension is firmer than the previous model. The swingarm is similar in design to the old one, but was strengthened. Front and rear remain fully adjustable. The transmission was given a heavier- duty, slipper clutch. The final drive ratio was slightly lower, and gears 5-6 were spaced farther apart, and gear HR HAYABUSA