The Kawasaki W650 Wasabi is a purpose-built sprint racer from German workshop Schlachtwerk: a machine stripped to the absolute minimum, engineered for one goal, and named after the Japanese condiment that makes your eyes water. Built to compete in the Sultans of Sprint series, the Wasabi takes the mild-mannered W650 and turns it into a genuine dragstrip weapon through radical engine surgery, weight reduction, and a nitrous injection system most riders would never dare touch.
What Is the Sultans of Sprint?
Sultans of Sprint is a European short-distance drag race series for custom motorcycles, held at iconic venues across the continent. Bikes are grouped by engine displacement and configuration, and the W650 competes in the air-cooled twin class up to 1,600 cc. The category is stacked: heavily modified Ducatis making over 200 hp with nitrous are not uncommon. Bringing a standard 650 cc parallel twin is, as the builder puts it, the equivalent of arriving with a knife to a gunfight. Which is exactly why Schlachtwerk's Tom Thörig called in the right people.
The Frankenstein Engine
Engine specialist Ulf Penner, known in the sprint community as the Engine Whisperer, merged W650 and W800 components to create something the factory never imagined. The displacement was bored out to 855 cc with forged racing pistons, a new cam, Carrillo connecting rods, bigger valves and a fully ported head. Despite all the internal work, the engine was made 9.5 kg lighter than the standard unit, and it retains the factory electric starter. A lower compression ratio allows the wet nitrous system to do its job: the setup runs Nitrous Express hardware managed by a Maximizer 5 control unit, with ignition timing pulled to accommodate the extra oxygen. New Dellorto 36 mm round-slide carburettors feed the mixture, and a 2-in-2 titanium exhaust system weighing just 1,750 grams expels it.
The Frame: 7.3 Kilograms of Structure
Chassis engineer Stefan Trautman designed a centre-tube frame that doubles as the fuel tank, holding 3.3 litres inside the main spine. No external tank, no wasted volume. The entire frame weighs 7.3 kilograms. Every component not essential to keeping the bike moving and stopping was removed. KTM rims carry a 320 mm brake disc with a four-piston calliper at the front, giving the Wasabi the ability to scrub speed at the end of the 200-metre run where Tom targets 175 km/h. The finished package is not the most powerful machine in the class, but it may well be the lightest.
The Experience Behind the Handlebars
Tom describes riding the Wasabi as being attached to a rocket. There is no comfort, no isolation from the road, no concession to normal use. Every vibration transfers directly. The horizon narrows to a single point and then disappears. That raw, unfiltered quality is what the sprint discipline demands and what custom motorcycle culture celebrates. For riders and collectors drawn to the same philosophy of removing everything unnecessary, the custom motorcycle selection at TheArsenale's motorcycle collection includes machines built with equal conviction. The Kawasaki Z 750 Zephyr MUCAkita is one example of another Japanese twin transformed by a specialist workshop into something entirely personal.
Read the full technical breakdown on Bike EXIF and the race report from Sultans of Sprint on Pipeburn.
Photo: Marc Holstein
