The engine power was reduced to 53 horsepower in 1993, according to the revisited power restriction code in Japan. Before 1993, the maximum power for a 400cc class bike was 59 hp. Cosmetic changes. 1993 was the last year for the SP (Sports Production) model.
All the larger motorcycles made for the Japanese home market are power restricted. Prior to 1993 the maximum horsepower were the following: 400cc class: 59 hp. The new limits for the models built in 1993 and after, were: 400cc class: 53 hp.
Although the medium and low speed range was improved by changing the weight and valve timing etc. and changing the valve timing, the maximum output is 53 ps maximum output and 3.8kg-m maximum torque due to change of the self-regulation value and power down on specifications. Headlight turned on at all times.
The SP specification also undergoes the same change as the 1993 model, but the valve timing is not changed, the maximum torque is 3.7kg-m/10000 rpm. The maximum output is the same as the standard. Pearl Suzuki Medium Blue only.
Suzuki GSX-R400 1993 Specifications
Colors White/Blue Light purple metallic SP model Pearl Suzuki Medium Blue
Dimensions and dry mass Type (frame code): GK76A Overall length: 1,995 mm (78.5 in.) Overall width: 710 mm (28.0 in) Overall height: 1,060 mm (41.7 in) Wheelbase: 1,435 mm (56.5 in) Ground Clearance: 125 mm (4.92 in.) Seat height: 735 mm (28.9 in.) Dry mass (weight): 167 kg (367 lbs)
Engine Engine type: Water-cooled DOHC inline-4, 16 valves Bore x stroke: 56,0 mm x 40,4 mm (2.205 x 1.591 in.) Piston displacement: 398 cc Compression ratio: 11,8 :1 Maximum power: 59 hp/ 12,000 rpm Maximum torque: 4,0 kg-m/ 10,000 rpm Top speed: about 200 km/h (124 mph) Starting system: Electric starter Lubrication system: Wet sump Carburetor: Mikuni 27mm x 2