Suzuki GSX-R 400R

Suzuki GSX-R 400R
Manufacturer	Suzuki
Production	1989 - 90
Class	Sportbike
Engine	Four stroke, transverse four cylinder, DOHC 4 valves per cylinder. TSCC
Compression ratio	11.8:1
Ignition	CDI
Transmission	6 Speed, constant mesh
Frame	Aluminum angular pipe double cradle
Suspension	Front: Telescopic forks Rear: Full floater swing arm, non-adjustable
Brakes	Front: 2 x Discs, 4 piston calipers Rear: Single disc, 2 piston caliper
Front Tire	110/70-R17 53H
Rear Tire	140/60-R18 64H
Wheelbase	1375 mm / 54.1 in
Seat Height	735 mm / 28.9 in
Weight	160 kg / 352 lbs (dry),
Recommended Oil	Suzuki ECSTAR 10w40
Fuel Capacity	15 Liters / 3.96 US gal / 3.3 Imp gal
Manuals	Service Manual

Engine

The engine was a Liquid cooled cooled Four stroke, transverse four cylinder, DOHC 4 valves per cylinder. TSCC. The engine featured a 11.8:1 compression ratio.

Drive

Power was moderated via the Wet multi-plate.

Chassis

It came with a 110/70-R17 53H front tire and a 140/60-R18 64H rear tire. Stopping was achieved via 2 x Discs, 4 piston calipers in the front and a Single disc, 2 piston caliper in the rear. The front suspension was a Telescopic forks while the rear was equipped with a Full floater swing arm, non-adjustable. The GSX-R 400R was fitted with a 15 Liters / 3.96 US gal / 3.3 Imp gal fuel tank. The bike weighed just 160 kg / 352 lbs. The wheelbase was 1375 mm / 54.1 in long.

Photos

Overview

Suzuki GSX-R 400R

In 1989 an extra ”R” was added to the model name. The new model name was GSX-R400R although the internal model code (frame code) remained the same.

A Production Racer version, GSX-R400R SP, was released in June 1989 with single seat, close ratio gear box, uprated suspension and different CDI.

The GSX-R400 got a new frame (GK73A) and new overall appearance in 1988. The new model was presented in February 1988. The redesigned GSX-R got once again new fairing and shorter wheelbase, but the weight increased a bit due to the stronger new chassis and exhaust system. The model also got slingshot carburetors, polished chrome silencers, curved radiator, Tokico 4-cylinder front brake calipers and a rear hugger mudguard.

The new 4 into 2 exhaust was meant to increase the torque on the mid-range band, but had only a marginal effect.

The 400cc series were increasing popularity in Japan and a production racer with different suspension and gearing, GSX-R400 SP (Sports Production) was presented for 1988. It looked almost identical with the standard GSX-R400 but didn't have passenger foot pegs and you could spot the rear suspension gas reservoir peeking out from under the seat. Also the front suspension was different from the standard model. The SP version also had a Sports Production logo on the tailpiece.

To compete in production racing, the manufacturers produce SP (Sports Production) versions of their sports bikes. These usually have fully adjustable suspension, close ratio gearboxes and a single seat but didn't have more power, due to Japanese motorcycle manufacturer's power restriction code.

The SP's are claimed to be even harder work on the road than a standard GSX-R400. Not that surprising knowing that it was designed for racing only.

Available colors: Blue/White, Black/Red/White, Black The SP model was available in Blue/White only.

Make Model	Suzuki GSX-R 400R
Year	1989 - 90
Engine Type	Four stroke, transverse four cylinder, DOHC 4 valves per cylinder. TSCC
Displacement	398 cc / 24.3 cu-in
Bore X Stroke	56 x 40.4 mm
Lubrication	Wet sump
Cooling System	Liquid cooled
Compression	11.8:1
Induction	Slingshot carburetors
Ignition	CDI
Headlight	12V 35/35w x 2
Starting	Electric
Max Power	44 kW / 59 hp @ 11000 rpm
Max Torque	39.2 Nm / 4.0 kgf-m / 28.9 lb-ft @ 9000 rpm
Clutch	Wet multi-plate
Transmission	6 Speed, constant mesh
Final Drive	Chain
Primary Reduction Ratio	2.212
Final Drive Ratio	3.066
Gear Ratio	1st 3.166 / 2nd 2.125 / 3rd 1.631 / 4th 1.333 / 5th .173 / 6th 1.083
Frame	Aluminum angular pipe double cradle
Front Suspension	Telescopic forks
Rear Suspension	Full floater swing arm, non-adjustable
Front Brakes	2 x Discs, 4 piston calipers
Rear Brakes	Single disc, 2 piston caliper
Front Tire	110/70-R17 53H
Rear Tire	140/60-R18 64H
Rake	27° 25'
Trail	96 mm / 3.7 in
Dimensions	Length 1995 mm / 78.5 in Width 695 mm / 27.4 in Height 1110 mm / 43.7 in
Wheelbase	1375 mm / 54.1 in
Ground Clearance	125 mm / 4.9 in
Seat Height	735 mm / 28.9 in
Dry Weight	160 kg / 352 lbs
Fuel Capacity	15 Liters / 3.96 US gal / 3.3 Imp gal