Worlds Most Expensive Motorcycle – AJS E95 Porcupine

AJs on Motoress

Presenting the World’s Most Expensive Motorcycle is the 1954 AJS E95 Porcupine motorcycle will be offered to investors during Bonham’s automotive auction in Carmel, California on August 18th. One of the most legendary motorcycles in history owing to its brief but astonishing racing success and extreme rarity, the example on offer at the Bonham’s sale is expected to fetch up to $750,000. If succeeded, this will shatter the current world record of $520,000. paid for a 1915 Cyclone Board Track Racer set in 2008. But as far as motorcycles go, the Porcupine is at the very top of the two wheeling class.

ajs motorcycle

This is just one of four E95’s ever completed, the Porcupine, so nicknamed because of the spiked cooling fins on its cylinder head, was created as a works racer by British manufacturer AJS. It is perhaps one of the most legendary motorcycles in history owing to its brief racing success and extreme rarity.  Because the number of AJS Porcupines is so scarce, each machine is well known, with all 1954 models being accounted for.

Until recently this particular Porcupine had been on display for more than two decades, occupying pride of place at the National Motorcycle Museum near Birmingham in the UK. It’s motor having been overhauled by Team Obsolete Equippe. The last Porcupine to sell at auction was the non-works, privateer-raced Tom Arter E95 Porcupine which made $258,500 at Bonham’s in 2000.


Introduced in 1952, the AJS E95 (AJS Porcupine) motorcycle was a much-redesigned version of the E90 horizontal twin, knows as the Porcupine again, due to the spiky finning on the cylinder head. The original design was drawn pre-war when supercharging was legal, but when racing resumed post war, supercharging was banned and the Porcupine was uncompetitive.

Only four of these machines were built. First revision the engine was carried in a double-cradle frame interrupted beneath the engine, and the machine appeared in the tourist trophy races, as did the three-valve single-cylinder 350cc 7R3. The following year, the E95 appeared with two separate cylinder heads instead of one common to both cylinders. The angle of the inlet points was reduced from 43 to 25 degrees to the perpendicular and the frame was also modified, gaining two side cradles supporting the engine. The end of works entries the final, 1954, MK 2 version was merely cleaned up aerodynamically, though it was not given a fairing. The front fork and steering head were shortened and the fuel tank was carried down over the flanks of the engine, so that a mechanical gas pump could be fitted, driven from the magneto shaft.

Low and compact, the ultimate version of the E95 was typical of the aerodynamic theories of the fifties. It was raced in the sixties by Mike Duff (Michelle Duff, Canadian!) and tuned by Tom Aster.

AJS E95 specifications

  • Engine: 497cc (68×68.5mm) air-cooled twin-cylinder four-stroke;
  • Engine: 54 hp @ 7500 rpm
  • Valves: Twin overhead camshafts driven by pinions
  • Fuel system: Carburettor
  • Transmission: 4-speed; Dry clutch;
  • Chain final drive suspension: Telescopic forks (front);
  • Swinging forks with twin damper units
  • Brakes: Drum (front rear) wheels: 19 inch weight: 335 lb