1974 Kawasaki 500 Mach III H1

Description

1971 Kawasaki Mach III: Debunking the “Widowmaker” Myth 

In 1966, Kawasaki experimented with the W1 twin, but the 1969 release of the H1 Mach III truly set them apart. Featuring a 498 cc, three-cylinder two-stroke engine producing 60 horsepower and weighing 382 pounds, the Mach III could reach a top speed of 124 miles per hour. Priced at $999, it offered incredible performance at nearly half the cost of Harley-Davidson's XLH. Its striking pearl white and purple paint, along with its exhilarating exhaust note, made it a sensation both in looks and performance. Kawasaki continued refining the Mach III, expanding the lineup with models like the H2 Mach IV 748 cc triple. By 1971, a front disc brake and strengthened frame were introduced, enhancing the bike's appeal. In 1974, the 498 cc Mach III H1E received valves to direct oil to the main bearings, improving engine durability. 

Highlights 

• Offered with 4,353 miles, believed to be original 

• A two-owner example, owned by the consignor since 1981 

• Exceptionally original 

• Finished in era-evocative Candy Green paint 

• Engine number (96553) close in sequence with the frame number and likely the original unit 

• The frame number (H1F26525) decodes as: 

  • H1F – Model Mach III H1 

  • 26525 – Sequential production number indication 1974 model year 

• Recent 2024 battery replacement with an original Yuasa 

• New set of plugs 

• New injection oil and new transmission oil 

• New airbox installed in late 1998 

Features 

• Performance (when new) 

  • Maximum horsepower: 59 hp/8,000 rpm 

  • Maximum torque: 41.2 ft-lb at 7,000 rpm 

  • Acceleration: 1/4 mile: 12.4 seconds 

  • Fuel consumption: 79 mpg @30 mph 

  • Braking distance: 35 feet @31 mph 

• Engine 

  • Type: two-stroke, three-cylinder, piston valve 

  • Displacement: 498 cc 

  • Bore and stroke: 60 x 58.8 mm 

  • Compression ratio: 6.8:1 

  • Ignition system: Electronic CDI 

  • Starting system: Kick 

  • Lubrication: “Injectolube” (oil injection) 

  • Engine oil: 2-stroke oil 

• Transmission 

  • Type: five-speed, constant mesh, return shift 

  • Shift pattern: N-1-2-3-4-5 

  • Clutch: Wet, multi-disc 

• Frame 

  • Type: Tubular, double cradle 

  • Suspension: Front: Telescopic fork, Rear: Swing arm 

  • Tire size: Front: 3.25 – 19 4PR, Rear: 4.00 – 18 4PR 

• Dimensions 

  • Length, overall: 2,125 mm 

  • Width, overall: 825 mm 

  • Height, overall: 1,100 mm 

  • Wheelbase: 1,410 mm 

  • Ground clearance: 145 mm 

  • Dry weight: 407 pounds 

  • Fuel tank capacity: 16 liters (4.22 gallons) 

  • Oil tank capacity: 2.3 liters (2.43 quarts) 

Known Imperfections 

• Carburetors will likely need cleaning after sitting for years 

• Tank has been emptied and flushed, small amount of rust along the bottom sides; no rust found in the tank filter 

Included 

• Tool pouch with Kawasaki tools 

• Kawasaki Shop Manual H Series 

• 1998 service receipt 

Ownership History 

The consignor’s brother-in-law purchased this 1974 Kawasaki 500 Mach III H1 new on 11 August 1973. It was later acquired by the consignor on 30 July 1981. In the past 43 years, the consignor notes that the bike has been ridden approximately 1,000 miles.