The GSX-R1000 K5 might have been launched to the world press Down Under but, there’s no doubt, the Gixer King is back on top of the heap…

I’m the first to admit that I’ve always had a soft spot for GSX-R1000s. I love the stonking engine and the rawness of the bike. There’s no denying it, though. Suzuki was getting well overdue for a new 1000 when the ZX-10R and R1 hit the streets and tracks in 2004. But, as if anything less was expected, the response from the street superbike Gods of Creation is nothing short of astonishing. Yes, Suzuki has raised the bar once again. And no, as is the case every year, I really don’t see how sportsbikes can get any better than this…

First off let get the technical stuff out of the way...

-- Engine --

The ’05 Gixer powerplant has been refined and re-worked to compliment the new chassis – starting with an increase in capacity from 987.7cc to 998.6cc through an increase in bore from 73.0mm to 73,4mm. Stroke remains 59.0mm. The basic engine dimensions remain the same despite the increase in bore, with cylinder pitch at 80mm and the same horizontally split crankcases and crank/input/output shaft layout as the K4. Cylinder angle is 23 degrees.

A new cylinder head features a more compact combustion chamber design with a higher compression ratio of 12.5:1 over the previous model’s 12.0:1. The higher compression ratio helps increase power and torque throughout the rev range while the new combustion chamber design and flat valve head, combined with larger intake and exhaust ports, contribute to better combustion efficiency. The new valves are titanium, replacing last year’s steel jobbies and saving 94.4 grams in the process. The lighter valves and heavier springs have enabled a 1000rpm higher rev ceiling.

New pistons and rings also help reduce mechanical losses, with the piston skirts new 8.9mm narrower and piston height 1.3mm smaller. And despite an increase in width of 0.4mm per slug, weight is down 32 grams in total. The rings are now chrome-nitride coated as opposed to chrome plated in the K4.

The crankcase ventilation holes have been increased in diameter to 39mm from 35mm, reducing piston/crankcase-pumping losses on the down-stroke, increasing power output. The crank has also been reinforced for 2005, as have the conrods which now have a larger I-beam section.

One of the most significant changes to the 2005 engine is the addition of a back-torque limiting, or slipper clutch, and closer gear ratios. Second gear remains the same as the K4 but first is taller and third through sixth much closer and more suited to the fast-revving engine than before. The slipper clutch allows for smooth corner entry, downshifting without the need to manually slip the clutch and better braking feel and composure. Great stuff.

As was the case in the K4, engine features an integrated cylinder/crankcase design, with SCEM (Suzuki Composite Electrochemical Material) coated cylinders. The engine also features a secondary balance shaft running on plain bearings. The radiator is a new trapezoidal shape, offering a reduction in size and an increase in efficiency. The air-cooled oil-cooler remains the same.

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