Starting in 1970, the only numbers used for the purpose of identification are on the right neck and frame downtube.

• The frame is stamped with a Vehicle Identification Number (VIN)identification.
• There are still other stampings on the different parts of the frame combined with certain features that can be used to date the frame.
  But the only numbers used to identify the entire bike for ownership purposes is the VIN number stamped in the right side neck.
• In addition to the neck VIN, an identification label is located on the frame giving the VIN and date of manufacture.
  This label was required by law for identification.¹⁾
• The serial number is the 3rd through the 7th digit. All serial numbers run consecutively regardless of model year. ²⁾

Click Here to view Ironhead Frame Identification in the Sportsterpedia for more information.
Click Here for more information on serial numbers and VINs in the Sportsterpedia.

VIN for 1973 Sportsters
Sportster Model Code (first 2 digits)	Serial Number (next 5 digits)	Manufacturer (second to last digit)	Model Year (last digit)
3A = XLH 4A = XLCH	10,000 and up	H = Harley Davidson	3 = 1973
Example: (4A13675H3) indicates a 1973 XLCH and is stamped on the right side engine case and on the frame with the addition of a label on the steering head showing the VIN and date of manufacture. 3)
Example VIN Reads: 4A13675H3
4A	13675	H	3

The engine serial numbers were still stamped in the case but longer used for identification purpose of ownership on 1970-up model Sportsters.

• The engine VIN is stamped on the right side of the engine crankcase between the cylinders.

• Engine type: 4 cycle Overhead Valves, 45 degree V2 ⁴⁾
• Displacement: 60.9 ci / 997.5 cc (1,000 cc advertised)
• Compression Ratio: 9:1
• Bore: 3.188 in / 81 mm
• Stroke: 3.8125 in / 96.8 mm
• Horsepower: 61 @ 6,200 RPM ⁵⁾
• Taxable Horsepower: 7.2
• Torque: 52 ft-lb @ 3800 RPM
• 4 Cams
• Oil pump pressure:
  • Idle, with spark retarded (Min: 3-7 psi)
  • Normal riding conditions: 10-14 psi (6 psi at 20 mph)
• Fuel System: Bendix/ Zenith I6P12 carburetor. Click Here to reference the main Ironhead carb page in the Sportsterpedia
• Spark Plugs
  • #4 for break.
  • #5 for everyday use and hard service.

What is the Current KBB Value? ⁶⁾

What is the Current KBB Value? ⁷⁾

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