We have seen Kawasaki Vulcan S inspired custom bikes before, but this one is definitely one of the coolest so far: meet The Underdog, a nitrous oxide guzzling sprint racer.

The bike was created for the Essenza Sprint Challenge at the Glemseck 101 festival in Germany. A race, which was won by one Carl Fogarty on a supercharged Triumph Thruxton R, but that’s a different story.


The stock Vulcan S is a pretty standard chopper, so turning it into a bike capable of competing in a sprint challenge was going to take some work. The design and chassis work was done by Warm Up Motorcycles, while the engine was tuned by Höly.

The original 649cc engine produced 61bhp, but after the Höly guys were done with it, the new nitrous oxide engine was pumping out 150bhp. The dry weight was also reduced to 185kg. not bad from a chopper!

Here’s the full spec and more photos:


Chassis & Design (by Warm Up Motorcycles):

  • Öhlins front fork
  • Galfer-discs front and rear
  • Spiegler brake calipers front and rear
  • Spiegler brake and clutch master cylinders
  • HE-spoke wheels, painted in body color
  • LSL footrest
  • LSL handlebar, -Handgriffe, -Rückspiegel, -Sturzpads and -Bobbins
  • small P & W headlights
  • Custom-tank lid
  • Warm-up cladding shell and -Höckersitzbank (self-supporting)
  • 3D Design by Dimitri Milonas
  • Original Vulcan S Fuel Tank
  • Intact lithium-ion battery
  • Emil-black chassis storage and tuning
  • Moto-Life-exhaust system


Engine (by Höly):

  • facilitated and finely balanced crankshaft
  • modified camshafts
  • modified cylinder head
  • modified injection Kawasaki Ninja ZX10-R, 43mm
  • 2 injectors per cylinder
  • Special Rods
  • Power Commander
  • Compression: 13,5: 1
  • Nitrous oxide injection
  • Lightened generator rotor


Technical specifications:

  • Liquid-cooled two-cylinder four-stroke in-line engine, 649 cc
  • DOHC valve timing, fuel injection
  • six-speed gearbox
  • chain drive
  • 150bhp
  • perimeter steel frame
  • suspension travel v./h. 120/100 mm
  • Front tire 120/70 ZR 17 rear 180/55 ZR 17
  • dual disc front brakes, rear disc brakes
  • empty weight (road ready) 185 kg
  • Fuel tank capacity 14 liters.

040_Holzner_Glemseck_Kawa.jpg.5239776 # 460_Holzner_Glemseck_Kawa.jpg.5240532 450_Holzner_Glemseck_Kawa.jpg.5240514 440_Holzner_Glemseck_Kawa.jpg.5240496 430_Holzner_Glemseck_Kawa.jpg.5240478 420_Holzner_Glemseck_Kawa.jpg.5240460 410_Holzner_Glemseck_Kawa.jpg.5240442 400_Holzner_Glemseck_Kawa.jpg.5240424 390_Holzner_Glemseck_Kawa.jpg.5240406 380_Holzner_Glemseck_Kawa.jpg.5240388 370_Holzner_Glemseck_Kawa.jpg.5240370 360_Holzner_Glemseck_Kawa.jpg.5240352 350_Holzner_Glemseck_Kawa.jpg.5240334 340_Holzner_Glemseck_Kawa.jpg.5240316 330_Holzner_Glemseck_Kawa.jpg.5240298 320_Holzner_Glemseck_Kawa.jpg.5240280 310_Holzner_Glemseck_Kawa.jpg.5240262 300_Holzner_Glemseck_Kawa.jpg.5240244 290_Holzner_Glemseck_Kawa.jpg.5240226 280_Holzner_Glemseck_Kawa.jpg.5240208 270_Holzner_Glemseck_Kawa.jpg.5240190 260_Holzner_Glemseck_Kawa.jpg.5240172 240_Holzner_Glemseck_Kawa.jpg.5240136 230_Holzner_Glemseck_Kawa.jpg.5240118 220_Holzner_Glemseck_Kawa.jpg.5240100 210_Holzner_Glemseck_Kawa.jpg.5240082 190_Holzner_Glemseck_Kawa.jpg.5240046 180_Holzner_Glemseck_Kawa.jpg.5240028 170_Holzner_Glemseck_Kawa.jpg.5240010 160_Holzner_Glemseck_Kawa.jpg.5239992 150_Holzner_Glemseck_Kawa.jpg.5239974 140_Holzner_Glemseck_Kawa.jpg.5239956 130_Holzner_Glemseck_Kawa.jpg.5239938 120_Holzner_Glemseck_Kawa.jpg.5239920 110_Holzner_Glemseck_Kawa.jpg.5239902 100_Holzner_Glemseck_Kawa.jpg.5239884 090_Holzner_Glemseck_Kawa.jpg.5239866 080_Holzner_Glemseck_Kawa.jpg.5239848 070_Holzner_Glemseck_Kawa.jpg.5239830 060_Holzner_Glemseck_Kawa.jpg.5239812 050_Holzner_Glemseck_Kawa.jpg.5239794

Tony Carter

Does this get you revved up? Tell us why...

Bikes for sale

Subscribe to MoreBikes Newspaper

Get MoreBikes delivered through your letterbox every month. 12 issues for £15. Click here for more information.

Get MoreBikes.co.uk Updates

Enter your e-mail address below and you will receive biking news straight into your inbox...

You can unsubscribe at any time.