I believe the following is correct but I am getting old.
Front Wheel 1997 has different/smaller wheel bearings distance spacer. Has 1J on wheel hub
1998-2003 share a common bearing/distance spacer. Has 2J on wheel hub
http://www.valkyrieforum.com/bbs/index.php/topic,79713.0.htmlFront Brake Rotor– All years, 97-03, are interchangeable.
Rear Brake Rotor 1997-1999 STD/Tourer use the early brake rotor.
1999 - 2001 Interstate and 2000-2003 STD/Tourer use the later rear rotor
Rear Wheel 1997-1999 STD/Tourer use the early wheel . Has 1J near wheel hub.
2000-2003 STD/Tourers and all Interstates use the later wheel. Has 2J near wheel hub.
Front Brake Caliper All years are the interchangeable.
Rear Brake Caliper All STD/Tourer are interchangeable.
Interstates are different, they have smaller pistons/pucks in the caliper.
Timing Wheel All years are interchangeable, the same.
ICU All STD/Tourers are the same.
Intrstate ICUs have two degrees more advance.
Carbs 1997 carbs supposedly use a different vacumm pistion, item #18 on fiche.
All STD/Tourers use the same vacuum piston spring, item #11.
Coolant Light 1997-1999 STDS/Tourers use the early wiring for the coolant light.
2000–2003 STD/Tourers and all Interstates use the later wiring.
http://www.valkyrieforum.com/bbs/index.php/topic,102407.0.htmlTurn Signals 1997-1999 use two screws per lense to retain the lense.
2000-2003 use one screw per lense.
Rear Fender_Rear Section 1998 and later have a reinforced rear fender to avoid fatigue cracking/drooping turn signals.
Speedometer/Tachometer Numeral Color All 1997-1999 Std_Tourer are green.
All 2000-2003 STD/Tourer are red.