On the road, the difference in acceleration between the two bikes feels even more dramatic than the dyno figures suggest. The second-generation bike absolutely walks away from the old bird in any gear or riding situation, whether from a dead stop or rolling on. Initially, this was confusing: Despite the 16-horse difference in peak power, the dyno charts for the '07 and '08 bike are virtually indistinguishable up to 8250 rpm, with essentially equal low- and midrange power. What's more, the '08 bike tips the scales at a shocking 29 pounds more than the '07 model, mostly due to the new, Euro 3-compliant exhaust. Looking at the numbers alone, the new bike should feel slower on the street; instead, the old bike feels like it's tied to a post. What gives?
The answer is revealed after you juggle the parameters of the dyno readout. Graphing horsepower against time instead of rpm shows that the '08 bike arrives at 8000 rpm more than a second quicker than the '07 bike--so it gets to the meat of its power more quickly. Suzuki's extreme efforts to make the new motor rev quicker pay big dividends on the street. These internal engine changes, along with slightly shorter gearing (now 18/43 for an overall ratio of 2.39, compared to 17/40 for 2.35 in '07), let the new bike spool up faster, giving the perception of more power.
Suzuki made numerous suspension upgrades to the '08 Hayabusa to better support a faster, heavier bike. Despite firmer spring and damping settings for both the Kayaba inverted fork and shock, ride quality of the new bike is actually smoother than the old. Ridden side by side, the first-gen 'Busa feels downright jitney-like, with excessive fore/aft pitching over freeway expansion joints and a tendency to blow through the travel at both ends under heavy acceleration or braking. The new bike, by comparison, maintains a level stance on even rough roads and offers more predictable action and increased chassis stability under heavy inputs--the benefits of an extra eight years of suspension damping technology advancements.
The harder you ride the two Hayabusas, the more distinct the chassis upgrades become. First, the brakes: Even with six pistons clamping down on huge 320mm discs, the braking system on the first-gen 'Busa is barely adequate. The second-gen brakes, updated with four-piston, radial-mount calipers, stop much better, with superior initial bite and more ultimate stopping power that is a great confidence-booster on such a big, brutally fast machine. Better brakes allow fitment of slightly smaller 310mm rotors--one of numerous changes, along with new three-spoke cast-aluminum wheels and a more rigid swing-arm--that reduce unsprung weight and improve turning ability. Indeed, the '08 model feels better in the curves, but this is likely more a result of improved wheel control from the updated suspension than the slight reduction in running-gear weight.