Powering the 2004 Quadsport Z400 is a high performance398cc aluminum-alloy 90.0mm X 62.2mm, four-stroke, liquid cooled, DOHC single cylinder powerplant with four valves actuated by cam lobes riding directly on bucket tappets. The cylinder head features a narrow 28 degree included valve angle for a compact, efficient combustion chamber with a 11:3:1 compression ratio.
Fuel is supplied by a 36mm Mikuni carburetor feeding 36mm intake valves, with exhaust leaving through 29mm exhaust valves. A dry sump lubrication system helps to create a more compact engine package. The aluminum-alloy cylinder is plated with Suzuki's own race proven nickel phosphorus-sillicon-carbide coating, to reduce weight and improve heat transfer, allowing for tighter more efficient piston-to-cylinder clearance.
A manual 5-speed transmission, with reverse gear transmits horsepower to the wheels, while a handy knob on the left front fender releases the reverse interlock to select the reverse gear with final drive transmitted through an O-ring sealed roller chain.
The chassis features a lightweight, rigid, high-tensile steel alloy tube frame and sub-frame, along with an independent double-wishbone front suspension with preload adjustable coil over shocks. Out back an aluminum alloy swingarm rear suspension utilizes a single fully adjustable piggyback reservoir shock.