1957 Sportster

• The serial number is stamped on the left side of the engine case. The first 5 or 6 digits represent the year and model ¹⁾

The Sportster XL was introduced as “a modern, up-to-date power plant.”

In 1952, the W models were replaced with the revered 45-cubic inch side-valve K series. The new K-models included an integrated four-cam engine and four-speed transmission design, along with foot shift, swingarm rear suspension, and telescopic front forks to compete with smaller, sportier motorcycles coming mainly from Great Britain. Essentially, the new XL motor was an updated K-model engine with larger displacement, overhead valves and higher compression. - Harley-Davidson Archives Copyright H-D ²⁾

Number produced: 1983³⁾

Original Price: $1103

• Model Designation: XL

• Engine type: 4 cycle Overhead Valves, 45 degree V2 ⁴⁾
• Displacement: 55 ci / 900 cc
• Compression: 7.5:1
• Hemi-spherical style heads
• Bore: 3 in⁵⁾
• Stroke: 3 13/16 in⁶⁾
• 90 Degree Valve Angle
• Horsepower: 42 @ 5,500rpm ⁷⁾
• Torque: 48 ft-lb @ 3600 RPM
• Fuel System: Linkert DC carburetor ⁸⁾

• Fuel capacity: 4 gal / 15.14 l⁹⁾
• Oil Capacity: 3 qts. / 2.83 l ¹⁰⁾
• Transmission Capacity: 1.5 pints / .71 l ¹¹⁾
• MPG: 50mpg (est.)¹²⁾

• Weight: 495 lb / 225 kg¹³⁾
• Wheelbase: 56.5 in / 143.51 cm ¹⁴⁾
• Overall Length: 87 in / 221 cm ¹⁵⁾
• Overall Width: 34 in / 86.36 cm ¹⁶⁾
• Overall Height: 40.5“ ¹⁷⁾
• Road Clearance: 2.5 in minimum / 6.35 c minimum

• Constant Mesh - Foot shift
• Speeds - 4 Forward
• Number of Sprocket Teeth
  • Engine: 34
  • Clutch: 59
  • Transmission: 21
  • Rear Wheel: 51
• Gear Ratios
  • 1st: 10.63 to 1
  • 2nd: 7.69 to 1
  • 3rd: 5.82 to 1
  • 4th: 4.21 to 1

• Front and rear: 3.50 x 18
• Tire pressure
  • Front: 14 psi / .96 bar
  • Rear: 18 psi / 1.24 bar

• XL

• Pepper Red / Black Tank Panels¹⁸⁾
• Skyline Blue / Birch White Tank Panels¹⁹⁾
• Birch White / Black Tank Panels²⁰⁾
• Black / Pepper Red Tank Panels²¹⁾

1957 Parts Manual²²⁾

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