Running Gear



Name: Suzuki GSX 1300RX Hayabusa (1999 model. for 2000 models substitute X with Y)

Dsiplacement: 1299cm-3



4 cylinder, Four-stroke, Liquid Cooled, DOHC, 16 Valve, TSCC power plant, with a compression ratio of 11.0:1. The wet sump lubrication system feeds the multi-plate wet clutch as well as the piston cooling oil jets and hydraulically damped cam chain tensioner. 

Ignition and ECM

Fully transistorized electronic ignition utilizes sensor outputs from the following...Atmospheric air pressure, Intake air pressure, Intake air temperature, Engine coolant temperature, Crank position, Cam position, Gear position and Throttle position, to determine which preloaded fuel and ignition timing map to use for a given set of variables. The ECM then delivers this map as pulses to the Denso injectors, altering duration for fuel enrichment, and to the plug coils, which are contained within the Denso plug caps, and ultimately to the NGK plugs. 

Fuel injection

Fuel is held at 43psi above intake pressure in the injector rail by the pump and the pressure regulator. Excess fuel is bled off through the return to tank line. This fuel is injected into the 42mm throttle bodies and mixed with pressurized air emanating from the twin ducts in the nose cone.

Through the inlet boots and into the head, the volatile mixture is split by a knifed edge and sucked into the Nikasil plated cylinders through a 4 angle cut valve seat. Once inside the cylinder it is compressed to 1200-1600kPa by 80.98mm pistons.

Ignition occurs at 4 degs BTDC at 1150 rpms, the exhaust gasses being being forced through the twin exhaust valves, and into the header pipe. 

[NB. for the 1999 models the base ignition timing is 4 degs for all cylinders. The 2000 models have 4 degs for the outer 2 cylinders and 11 degs BTDC for the middle 2 cylinders. The 2001 models have reverted back to 1999 cylinder timings.]


On exiting the head, fresh air is injected into the exhaust gases via a PAIR valve, which sucks clean air from the air box. This is to aid burning of the remaining volatile substances as they pass through the exhaust pipe, the dual catalytic converters and out of the dual end cans.

Crank and clutch

The one piece crank drives the outer clutch basket as well as a balancer shaft situated at the front left of the engine, designed to reduce vibration.

The clutch is of a wet multi plate type, with 10 fibrous and 9 metal plates, of differing thickness. The clutch utilizes a back torque limiter system to reduce the likelihood of locking the rear wheel under high rev down shifts. It also acts as a ramping clutch under high torque situations. The clutch actuating mechanism is operated by a hydraulically controlled slave cylinder and push rods coming through the crank case and centre of the fore most gear shaft.


The gearbox is a 6 speed 1 down, 5 up sequential box, with constant mesh straight cut gears. The gear dogs are slightly undercut as standard. Oil cooled and lubricated with the same oil as the engine and clutch pack. The output shaft incorporates a cross shaped collar that is detected by the proximity detector of the speedo pickup mounted on the sprocket cover.

Final drive

With standard sprockets of 40/17 a final reduction ratio of 2.32 is achieved, allowing a theoretical top speed into the 10,800 rpm limiter of 196mph. Claimed factory stock power figures are 150rwbhp. The chain is a 112 link O-ring 530 type. Recommended rear tyre to get this power to the ground is the Bridgestone BT56J 190/50/ZR17 rear section


The Hayabusa, being designed mainly with aerodynamics in mind, has one of the lowest Coefficients of drag of any big bore motorcycle. The numbers, I shall look up and add when I find them!! hahahaha


If you can see any errors or omissions in the above, please contact me with the correction!!