See also, Catalog of Aftermarket Flywheels in the REF section of the Sportsterpedia.
Click on a pic to enlarge:

• Pre AMF 900 flywheel marks: ¹⁾
  • The single vertical line is the 45° advanced timing mark for the front cylinder.
  • The double vertical lines are the 15° advanced timing mark for the front cylinder that's used to set retarded kick start timing.
  • The dot is TDC front cylinder.
  • The AMF Sportsters used double dots for rear advanced timing.

65 OEM Flywheel 2)

• 1973 1000 flywheel marks: ³⁾
  • The vertical line is advance mark for the front cylinder.
  • The single dot is TDC for the front cylinder.
  • The double dot is advanced timing for the rear cylinder.