Compared to the nineties models the new GSX-R  600 is 11 kilograms lighter, 25mm shorter in overall length and 30mm shorter in overall height.  The smaller and more slippery shape has helped achieve a 4% reduction in aerodynamic drag.

The engine is more compact, lighter and more powerful.  It's basic design mirrors the latest GSX-R 750 engine, but with many unique parts of it's own.  Common features include DOHCs with liquid cooling and a downdraft TSCC (Twin Swirl Combustion Chamber) cylinder head carrying four valves per cylinder, hollow camshafts driven off the right-hand side of the crankshaft by a link-plate chain.

The crankshaft and transmission shafts are staggered vertically on two separate, horizontal crankcase splits to reduce engine length front-to-rear, the crankshaft is carried on the upper crankcase split and the transmission shafts are carried on the lower crankcase split.  Besides making the engine shorter, this semi-cassette type design allows the transmission assembly to be removed without disturbing the crankshaft.

Internal passageways in the upper crankcase and cylinder block carry lubricating oil to the cylinder head, eliminating external oil lines.  Shot-peened connecting rods carry lightweight forged pistons.  The clutch has coil springs with cable actuation for better feel with a revised lever ration for a lighter lever pull.

Compared to the previous model the new GSX-R 600 has a larger bore and shorter stroke, 67x42.5mm instead of 65.5x44.5mm, to reduce mechanical losses at high rpm.  The valves are now set at 28 degrees instead of 30 degrees in a combustion chamber which raises the compression ratio from 12.0:1 to 12.2:1.  The downdraft angle of the intake ports is steeper, 44 degrees instead of 41.5 degrees and the intake valves are larger, up from 26.5mm to 27.2mm, but the valve stems are narrower.  Overall the new cylinder head is 9.5mm shorter front-to-rear and 6mm shorter from the head gasket surface to the top of the cam cover and weighs 900grams less than the previous version.

The crankshaft sits in smaller main and big end bearings and the new con-rods carry 14mm tapered-bore wrist pins.

Fuel injection makes an appearance on the new GSX-R 600 and is a similar system to that used on the GSX-R 1000 except in the 600's case the throttle bodies are 38mm items.

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