Kawasaki Zephyr 400




Make Model

Kawasaki Zephyr 400


1989 - 91


Four stroke parallel twin cylinder. DOHC, 2 valves per cylinder


399 cc / 24.4 cu-in
Bore x Stroke 55 х 42 mm
Cooling System Air cooled
Compression Ratio 9.7:1


4X Keihin CVK30 carburetors


Full transistor

Starting Electric

Max Power

49 hp / 36.8 kW @ 11000 rpm

Max Torque

3.1 kgf m / 22.4 lb-ft @ 10500 rpm

Clutch Wet multi disc


6 Speed 
Final Drive Chain

Front Suspension

Telescopic forks

Rear Suspension

Dual shocks

Front Brakes

2x discs

Rear Brakes

Single disc

Front Tyre


Rear Tyre

Rake 27°
Trail 102 mm / 4.0 in
Wheelbase 1435 mm / 56.5 in
Seat Height 770 mm / 30.1 in
Ground Clearance 120 mm / 4.1 in

Dry Weight

179 kg / 395 lbs

Fuel Capacity 

14 Litres / 3.6 US gal

The Kawasaki Zephyr is a range of retro-styled naked superbikes, manufactured during the 1990s. All models were built by Kawasaki with air-cooled, transverse inline, dual-overhead-cam, four-cylinder engines. There were a number of Zephyr models available, in four engine capacities - 400, 550, 750, and 1100cc.

The 400 was produced for Japan due to the demand for 400cc motorcycles in that market. It was very popular. Many aftermarket parts were produced, with companies like Over Racing producing exhausts, swingarms, fairings and engine modifications.

Zephyr styling is roughly based on the old Kawasaki Z1, with twin shock rear suspension, a relatively upright riding position and air-cooled power units. The 400, 550 and 750 engines were developed from the old Z400/500/550/650/750/900 series. The 1100 engine is a re-engineered version of a liquid-cooled powerplant and is the only Zephyr built with two spark plugs per cylinder. The Zephyr offered the customer retro styling coupled with simplicity and reliability. Performance of the line was adequate for normal riding and the engines were tuned for low to mid range power.

The Zephyr started the Naked/Retro bike boom in the UK and Europe in the early 1990s and for a while moved Kawasaki to the 2nd best selling manufacturer of motorcycles in the UK Market.

The Zephyr Z750 engine reappeared in the late 1990s in the short lived ZR7.

The Zephyr 1100 had a Z1 restyle in its last year of sale including a return to wire wheels. Wire wheels also appeared on the 750. It was replaced in the Kawasaki UK range by the popular Z1100R styled ZRX1100 (later ZRX1200).

The ZRX series of motorcycles had a great impact on the growing market for retro style motorcycles, particularly in the United States. It was modeled after Kawasaki's superbike championship winning KZ1000R-S1 that propelled Eddie Lawson to Superbike dominance in the early 1980s and even spawned an international owners association known as the ZRXOA (ZRX Owners Association).