2009 Suzuki GSX-R1000 K9 - Ultimate Makeover
When we last left the GSX-R1000, it was in dire need of an update. It had gradually picked up pounds over the years to the point that it was now the heaviest of the literbikes by a good margin, and its formerly class-leading engine had become an also-ran in the chase for class supremacy. Even its superb steering and handling characteristics had long since been surpassed by the competition. No doubt about it, the Suzuki is a prime example of what can happen when you've lain dormant since '07.Wait a second…that's only two years, right? And we're talking about the GSX-R as if it's some dinosaur whose time has long since past?
Yep. Two years—heck, even one year—is all it takes to go from the latest and greatest to the back of the pack in a class as competitive as the literbike category. The pace of development has ramped up to unbelievable levels, and sitting still for just a moment often means getting left behind by an ever-improving pack.
Definitely Not The Same Ol' GixxerWe initially previewed some of the basic changes to the new GSX-R1000 in our January issue ("New GSX-R1000 for '09"), but the important details finally came to light at the U.S. press introduction held at the high-speed confines of Willow Springs International Raceway in Rosamond, California. Unlike the previous bi-annual changes that were evolutionary in scope, the K9 model is truly an all-new machine from the ground up, with very few components interchangeable with the old model.Although the previous generation K8 engine was a superb powerplant (as evidenced by its continuing dominance of AMA Superbike), Suzuki saw the writing on the wall and knew the next version would not only have to be lighter and more compact, but also need to rev higher in order to produce more power. This resulted in a new more oversquare bore/stroke layout, with a 1.1mm-larger bore (now 74.5mm) paired with a correspondingly 1.7mm-shorter stroke (now 57.3mm); nonetheless, the GSX-R still has the longest stroke in the literbike class. By combining the new forged aluminum pistons with new 0.5mm longer connecting rods for more leverage over the course of a crankshaft power stroke, Suzuki engineers aimed at retaining the previous generation engine's strong midrange power while also permitting higher top-end power potential.
The larger bore permitted 1mm larger titanium valves on both intake and exhaust (now measuring 31mm intake and 25mm exhaust) along with dual valve springs replacing the previous single units for better control at high rpm. An incremental boost in compression ratio from 12.5:1 to 12.8:1 was made possible by a slightly shallower included valve angle (the exhaust valve angle changed from 13 degrees to 12.5 degrees, for an included valve angle of 24.5 degrees) to prevent "shrouding" against the cylinder walls at lower valve lifts. Intake ports have been reshaped to work with the larger valves and higher rpm potential, as have the camshafts, with the intake cam made shorter for less weight by relocating the cam angle sensor.The crankshaft features redesigned oil passages, with the rod journals fed separately through the crankshaft end instead of through the main bearings. This would presumably allow lower oil pressure (and less power loss driving the oil pump) because the pump won't have to overcome as much pressure bleed and centrifugal force to feed the rod bearings at high rpm. Also reducing frictional losses is a counterbalancer with a smaller 20mm shaft bearing diameter. As is becoming increasingly common with inline four-cylinder engines, the mainshaft positioning has been stacked closer together (the crankshaft and mainshaft are now 59.7mm closer), which not only shortens the engine but also allows a two-piece (instead of three-piece as before) crankcase assembly for less weight and greater strength.Other small yet vital changes include the clutch switching from hydraulic back to cable operation for improved feel, as well as an increase in plate diameter (offset by one less plate), different friction material, and revisions to the back-torque limiter. The race-inspired trapezoidal radiator is 16.3mm thinner for less weight, and the new oil cooler now replicates the factory racing components, with a trapezoidal housing and different fin design that boasts a narrower profile along with much better heat dissipation. The twin muffler under-engine exhaust is retained, but the mufflers themselves are now made entirely of titanium, and the exhaust system as a whole dropping approximately 400 grams from last year; also returning is the SET exhaust valve, with the stainless steel under-engine chamber carrying the catalyzer to reduce emissions.The all-new twin-spar aluminum frame is comprised of five precision cast sections for improved rigidity balance, as well as relocating the welding points to keep them out of sight for better appearance. As expected, the more compact engine allows the main frame section to be shorter and the swingarm made longer to increase traction and rear suspension performance. Wheelbase has been shortened by 10mm to 1405mm (55.3 inches), while the swingarm has been lengthened by 32mm yet weighs in 500 grams lighter; a more progressive rear suspension linkage helps counter the squatting tendencies under power of the longer swingarm.
Crucial unsprung weight has also been lost from the cast aluminum alloy wheels, with 180 grams dropped from the front wheel and 230 grams less in the rear. OEM-spec Bridgestone BT-016 rubber now graces the big GSX-R's hoops, offering superb traction and handling. New monoblock four-piston Tokico front brake calipers highlight the changes to the front brake system, with the 23-percent-stiffer cast aluminum units sporting a 10 percent greater master cylinder ratio for more responsive and progressive braking. The complete front brake system has dropped a total of 560 grams, with 30 grams each coming from the new design 310mm discs with aluminum floating pins. Even the rear brake system drops some 290 grams by using a more compact caliper with a piston diameter nearly 8mm smaller than before yet maintaining the same braking power.On the suspension front, the big Suzuki gets the same Showa 43mm BPF (Big Piston Fork) as the '09 Kawasaki ZX-6R, albeit with a 39.6mm internal piston versus the Kawasaki's 37mm unit. As with the ZX-6R, the simpler construction of the BPF drops 720 grams compared with the conventional cartridge fork, and the rear suspension also underwent a weight loss program, with a smaller piston and thinner shaft contributing to a 300-gram weight loss for the rear shock, and the linkage is now made from extruded rather than forged aluminum.
Got Speed?Suzuki introduced the new big GSX-R at the high-speed confines of Willow Springs International Raceway's nine-turn road course, which would quickly reveal whether the new model was lacking in top-end speed, as well as high-speed stability through the daunting 130-mph bumps of Turn Eight.
The new GSX-R may not look that much different from the saddle, but its narrower midsection and smaller overall feel are immediately noticeable. Seat height is the same at 31.9 inches, but feels lower due to the narrower seat that allows your legs more room to reach the ground. Clutch action is vastly improved with the cable-actuated version, offering much better feel and feedback.
0 Responses

Post a Comment

  • counter