Gixxers in the Mist

GSX-R 600

Misano World Circuit
Santa Monica, Italy
February 24-25, 2008

The good news for GSX-R 600 racers is that the new bike offers scant advantages over the old model. A well tuned 2006 or 2007 model will be able to lap competitively with the 2008. If the engine in your current race bike has a few too many weekends on it and the prospect of replacing the 3-4 gear cluster and all of the titanium valves is a little to daunting then the better news is that all of your suspension parts will swap over to the new model.

There is one caveat to this dynamic.  The 2008 has a 32 bit CPU with 300% more memory than the 2007 model and a mode switch on the handlebar. In stock trim the mode switch just makes the bike run slower but, if the GSX-R 1000 experience is any indication, a Yoshimura ECU swap will convert that toggle switch to a simple traction control setting. Although 600s with modern 180 rear tires do not generally need much help keeping the tire from spinning the traction control could offer a significant safety margin for a racer on the edge, or a constrained tire budget.

After years of introducing new GSX-Rs to the world’s press in sunny Australia Suzuki decided to get back their roots of press launches in Northern Italy. Northern Italy, with a surfeit of culture and beauty, can also be a little hit or miss with the weather during the winter. In this case we missed.

In fifty-degree temperatures a thick pea fog obscured the newly redesigned Misano circuit for most of the two days of the launch limiting the number of laps and discouraging rambunctious riding antics.

Brian Nelson searches through the mist to photograph
Sam Fleming searching for traction on a cold foggy day in Italy.

Fortunately this year’s GSX-R is only the two-year revision for the 600 which meant that most of the changes are relatively minor and more focused towards power delivery (relatively easy to evaluate on a cold slippery track) than the lateral chassis flex affecting front end chatter (relatively difficult to evaluate, much less on a cold damp track). At some points the fog on the track was so thick that I could not see the apex curbing from the entrance curbing. The mist condensing into droplets on my visor served to be enough of a yellow flag such that, even without the ocular challenges, I never really felt the desire to throw the 600s into one of Misano’s undulating apexs with commitment and abandon.

I turned my attention from my dismaying lack of confidence in the track surface (which by no means is a reflection on the suspension or the Bridgestone tires but simply because damp cold tracks as sketchy) to the revisions to the 600.  From the cockpit the two major revisions are the engine revisions to improve the mid-range throttle response and the brake leverage ratio changes.

The engine has been tuned to fill out the area under the curve.  With the basic characteristic of the GSX-R high revving and competitive engine left intact, the changes to the intake tract and exhaust pipe have added 3 to 4% throughout the powerband.  The top end power remains unchanged but the enhanced mid-range allows for faster acceleration in all gears as well as improved throttle response making the GSX-R easier to ride in it's stock form.

Careful reworking of the header pipe matched with intake tract and cam
changes have increased mid range power without sacrificing top end.

The smaller master cylinder gives more travel at the lever. This was welcome in the tricky conditions as the overall stopping power of the system was ample and the longer lever travel made it easier to trail the front brake while balancing the desire to neither enter a fog shrouded corner with too much speed nor overtax the DOT tire on the cold damp track.

« 2008 pulling stronger from 7,000 on up.

These revisions to the bike will, ultimately, probably have little relevance to racers as the smaller master cylinder will be more prone to fade and the mid-range enhancements may be sacrificed for more top end however, for street and track day riders both of these changes will be welcome.

The slipper clutch has received slight modifications which seemed to be more aimed at durability than performance. The slipper clutch worked flawlessly to the point where even downshifting into 1st gear failed to induce any rear wheel chatter. Only carrying the rear wheel slightly in the air with the front brake could induce wagging from the rear. The shifter seemed slightly more gritty that previous GSX-Rs. Whether this was due to the clutch revision or internal friction in the shift drum could not be decisively ascertained but my guess would be that the shift drum and shift forks could do with a little more polishing before assembly.

The rest of the GSX-R is a welcome and familiar platform. The chassis is taunt and nimble even across Misano’s uneven surface. The bike’s new speed controlled steering damper keeps the bike from wobbling in Misano’s fifth gear full throttle kink but allows the steering to be light and neutral in the pits and in the slow speed turns.

The rider ergonomics are identical to the 2008-2007 which is to say that they are more cramped than the GSX-Rs of old but are a little more roomy than some of the other 600s.

The 2008 GSX-R has be re-tuned to ever so slightly round out its street credentials but it will remain one of the dominant race bikes at the track.

New Skin, Same Skeleton.

Your correspondent suspects that the two best things about the new GSX-R 600 were not apparent in the riding at Misano. The first is the “mode switch” and the second are the new headlights. The mode switch is basically stupid in its stock configuration as all it does is make the 600 seem really slow. However, with the ECU and sensor enhancements on the GSX-R there is a very strong possibility that the mode switch, when coupled with a Yoshimura ECU, will provide rudimentary traction control on the 600. The second stealth feature of the 600 is the new headlights.  With a pair of low beams to the sides and a center high beam this bike promises to have the best headlights on a sportbike.  Given the awful headlights typically fitted to sportbikes (R1, Ducati, ZX etc) the attention that Suzuki paid to this is welcome.

Endurance racers and street bike riders rejoice. These headlights
look to be the most functional on a sportbike since 2000.

The consistent criticism of the latest generation of high revving 600s is that they are very peaky with gutless midrange. To flesh out the GSX-R for its two year make over the 600 has received some subtle tuning to flesh out the previous model’s somewhat anemic mid-range without compromising its top end performance.  This results in a bike with an close to identical top speed but with enhanced acceleration. The faster acceleration allows for more speed between the turns and a broader power band with which to work.




















The 2008 has been slightly reworked to make a better streetbike without sacrificing
any of its race track potential.

These small changes include a slight boost to the compression ratio (12.8 from 12.5), bigger internal crankcase ventilation holes (41mm from 39mm), revised dual fuel injectors per cylinder (8 hole instead of 4 hole injectors for better fuel misting), tapered throttle bodies (outlet diameter is reduced from 40mm to 36.5mm). The cam lift has been reduced from 8.6mm to 8.2mm and the exhaust pipe diameter has been reduced from 38.1 to 35mm. The entire capacity of the exhaust system has been greatly expanded to increase power with the unintentional side effect of increased weight.

The smaller exhaust pipe, throttle bodies and cam lift will all enhance low to mid-range power by increasing the velocity of the intake gases at lower engine speeds.  The compression ratio increase, the more expensive fuel injectors and the exhaust pipe help the bike retain the same maximum horsepower. The exhaust pipe has a computer controlled valve which is there, officially, to enhance low end power and unofficially to help the GSX-R pass noise tests.

The engine sports some other mild chances, iridium spark plugs, a hydraulic assisted cam chain tensioner (using oil pressure to pre-load the cam chain to reduce cam chain noise when the chain is between notches on the cam chain tensioner).  Small anti-resonance ribs have been added to the clutch cover and oil pan to reduce that characteristic Suzuki engine rattle.

On the handling front the new GSX-R gets some very subtle changes. The 600 inherits the electronic controlled steering damper that increased the hydraulic resistance by reducing the effective diameter of the oil orifice at higher speeds while still allowing for easy parking lot maneuvers. The 600 also gets slightly lighter wheels with a different spoke pattern over its predecessor fitted with new Bridgestone BT-016 Hypersport tires in the classis 120/70ZR17 and 180/55ZR17.  The forks, shock, frame, swingarm and other chassis parts remain the same from the 2007.

The perfect combination of GSX-R and apex.

The brake system receives a variety of revisions to reduce lever effort. The rotors have been thinned down from 5.5 to 5mm. This was the thickness of the 310mm diameter rotors in 1997 which caused some issues with rotor warpage when coupled with high friction brake pads. These rotors have been beefed up with 12 floating pins from 8 to try to mitigate that heat warpage but only time will tell if that will be enough for race bikes. The hydraulic ratio of the master cylinder to the brake calipers has been reduced to reduce lever effort and give more feel. The radial master cylinder is still linked to radially mounted calipers but the diameter of the master cylinder has been reduced from 19.05mm to 17.46 while the caliper pistons have been reduced from 34/30mm to 32/30mm. Smaller master cylinder diameters allow for more leverage on the calipers which reduces lever effort but can also lead to a loss of brake feel once the system gets hot and the system gets mushy. Our track riding was in poor weather on a flowing race track which is not conducive to punishing the brake system. My guess is that the older one will feel better on the sixth lap at Summit Point at the 3rd brake marker for turn one than the new brake system.

The excellent slipper clutch gets some revisions to refine the feel and slip of the unit. The clutch gets an additional clutch plate, revised friction material, and a slight reshaping of the drive-cams.

Reversible shift levers (like this one) should be mandatory on any bike that calls itself
a sportbike. 
Footpegs are position able and look like they would break away in a
crash before incurring frame damage. The same cannot be said for the subframe.

The footpegs retain their three-position 14mm (both horizontal and vertical) adjustability and the shift lever can be easily flipped from standard to GP shifting. The GSX-R picked up five pounds from 2007 but a visual inspection finds that all of that weight is most likely incurred in the new exhaust pipe and, therefore, will be easy to eliminate with a simple pipe swap.

Homely perhaps but at least it won’t overheat your ass in summertime traffic.

Absolutely gorgeous race adjusters fitted to
a sample race bike at the track of a source unknown.

The 2008 has received new bodywork, integrated LED indicators and suitable revisions to its lines which, in your correspondent’s eye, work exceptionally well from the aero-dramatic ram air intakes and butterfly winged headlights to the upswept tail section.

It is also available in white, red, blue and yellow.

The 2008 is available in blue, red, yellow, white and black and will be in the dealers before this issue is in your mailbox for $9,399.