It's all in the Breathing, Mixing, and Mapping A description of engine development can no longer start at the powerplant under a gas tank but has to begin at the nose of a sportbike where its ram air system opens to introduce the flow. Now the headlight has been made narrower and the intake openings reach in towards the center of the bike's nose where there is the highest pressure of air at speed. From there, the intake snorkels bellow out before narrowing down again and passing through the frame spars and into the intake area of the airbox, which has been enlarged to increase the volume and velocity of air reaching the velocity stacks.

Suzuki achieved the improved performance of the efi system a number of ways. They upgraded the Electrical Control Module (ECM) by increasing its thinking power from 8 bits to 16 bits, and by increasing the remembering power of the ROM (Read Only Memory…of course) from 32 to 96 bytes.

But more important than how much smarter the efi system is is that it now has more tools for its smarts to work with. Upstream from the throttle butterflies is a "secondary throttle butterfly valve system" that is intended to improve throttle response by controlling the intake area and maintaining intake air velocity.

Monkey in the Saddle The first two things that stand out about the new GSX-R750 are the seating position and the general feel of the steering. That might not sound very stunning at face value but it is because these two things are so much different from how they were with the last generation of GSX-R. On the new bike, you sit on it rather than down in it so there is no longer that feeling of being locked into position. Moving around on the bike through tight transitions takes less effort,

And the general steering feel? The last version of the GSX-R had a feel like no other sportbike that was somewhere between the Ducati 996 and most everything else. That's not to lump 96% of all sportbikes into one group but only to say that there is a general feeling that most have, although some bikes within that feel can handle distinctively better than others of that same underlying feel. The Ducati supersport bikes simply have a feel completely all their own, and the last generation of GSX-Rs was halfway between the Ducks and other sportbikes. None of this is to voice a preference. The point is just that the new GSX-R has that more popular feel.

The new GSX-R750 steers easily, quickly, and confidently, and trail braking into the turns can be done with comfortable assuredness. The bike never exhibited a tendency to drift or push. It also held a line well under mid-corner braking adjustments which is a popular and unavoidable test on unfamiliar tracks.

The limiting factor on the Misano track - where the press introduction of the GSX-R750 was held - was the Michelin street tires. Having both ends slide created visions of Italian doctors with saws and other construction tools and was adequate incentive not to pull the trigger all the way until clear of the corner's apex.

The power of the new GSX-R is nothing short of impressive in delivery, quality, and quantity. The bike will pull the front off the ground in second gear without working at it and the engine's low end is distinctly unlike that of the last GSX-R. It is plentiful. As mentioned earlier, the new redline is at 14,000 rpm but the engine isn't at all peaky, like the last version of the bike. Higher revs with a flatter feeling power curve is a remarkable achievement.

It's notable that 14,000 rpm takes time to get used to. I realized after a few laps that I had to resort to looking at the tach to acquaint myself with the proper shifting points because I had a tendency to shift early, at an old fashioned rpm, a.k.a. too low. Suffice it to say at this point that we wonder how this GSX-R750 bike will stack up with the bigger bore bikes even more than where it will fit in with its direct competition.

One other significant note about the new engine is the way in which the rev limiter functions. It comes on smoothly rather than the normal hammering of the rider, probably because it cuts out the fuel flow rather than the ignition. Once I started using all of the bike's revs, and then some, I just thought that it had a bothersome flat spot at around an indicated 14,500 rpm. Thought of that flat spot is an interesting new concept that one could only come to by conveniently ignoring the ramifications of a 750 revving to 14,500 rpm.

I must admit that on the Santa Monica circuit I saw a number of bumps, but I only felt a few of them. Either the GSX-R's chassis is that good or the track had what must have been merely full-scale photographs of bumps glued to its flat surface; matte photos, glossies would have been too slippery. On the exit of the chicane, there were waves in the pavement and these were easy to feel because, off of the best line, the rear tire would jump out where the road went away. It was not a good place to try to make up time. But other than that, and the undulations mentioned above in the fast left, the track felt smoother than it looked.

In the first day, it turned out that we only had two track sessions, so I waited until the second day to ask for any suspension changes. I'd noticed that, in the two hard braking areas on the track, the front end had been chattering so I asked for a little more preload and compression damping in the forks. They put in a half turn from where we had started with the settings and a quarter turn more damping. This cured the chattering completely. The settings are listed in a box for your convenience.

I later had them add a quarter turn of rebound damping in the front because, in the chicane's fast transition from right to left and off the brakes and on the gas, the bike porpoised unnecessarily. This change too was enough to settle the bike down and the chicane could then be taken with much less effort, and smoother and faster than earlier.

After understanding how the bike felt with those changes, I asked for a little more spring in the rear and was given a half turn, which amounted to a sag that measured out to just a hair under an inch. That was the last change made to the bike and, at that setting, it was the easiest to ride. I could have gone further with any of these changes to see if the bike got better or worse, but with only two days, there wasn't enough time. That's why we do full tests.

Of the GSX-R750's four-piston Tokicos, rather than the six of the recent past, I never found myself wishing another piston and the brakes were certain and consistent at every corner and every lap of the test. As mentioned above, it was the suspension that was at first overloaded, not the brakes.

Between the journalists' sessions on the track on the second day, Kevin Schwantz did some laps by himself on a GSX-R set up just for him. So, near the end of the day, I took a look at how Schwantz's bike was set up. At first I was confused and assumed great disappointment in myself. Schwantz's bike was set up way soft! He had taken out three-quarters of a turn of spring in the rear and had left all of the damping as the bike had been delivered. How could it be possible that this world champion would not be putting more forces into the suspension than I? So I asked him.

Kevin replied that, "Any production fork is going to bottom out under hard braking so I just learn how to adjust my riding style. I get off the brakes sooner so that the bike is balanced in the corner. I enter wider and don't trail-brake." Schwantz went on to say how he is not a suspension or setup guy and that that stuff never meant a lot to him. He just always worked at finding a way to ride whatever it was that he had to ride. And that really shouldn't have been surprising to hear. Schwantz is not a

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