Click Here to reference Sportster VIN Information in the History section of the Sportsterpedia.

1973 frames have differences in construction but the frame itself is still generic. ^{1) 2)}

The part number changes for 1973 frames do not reflect the different construction changes and are a bit confusing. The early part number is the same for E73, 74, 75 and 76 models. Normally you'd think the frame is the same each year (except L73) because of that. Normally you'd think the L73 frame just got the rear bracing which spawned the L73 part# change. But the 74-76 part# reverted back to the 1973 number.

Part numbers:

• E1973, 1974-1976 XLH/XLCH (47014-73)
• L1973 XLH/XLCH (47006-73), Note: E1973 frame part# sold as a replacement for this frame.

Construction differences:

• The early 1973 frame is the same as the 1972 frame (cast rear and neck).
• Mid 1973 frame uses the 1972 and down neck casting and the rectangular bar replaces the old seat casting.
  These frames had no diagonal supports for the new rectangular bar seat area.
  This is the first frame that was not sweat brazed at the factory. It was welded. These frames are kinda rare.
• Late 1973 version 1 used the new neck casting and no diagonal supports.
• Late 1973 version 2 now has diagonal supports.
• Mid/late 1973 frames used the new tank and brackets.
• 1974-1976 frames are the same as the L1973 frame version 2.

In L1974, the diagonal rear bracings were added to 1973 frames without them.
Adding the diagonals was a factory safety recall for mid 73-E74 (there is a pn in the 76 and 78 parts catalogs for the kit).
Without the braces, the rectangular bar would bend. This allowed the tire to contact the fender. When that happened, the tail lite and tires got wrecked. That = recall.
See “l973 XL, XLCH Frame Reinforcement / Tail Lamp Mod” below for more information.

A bend in the frame backbone on the right above the motor mount bolt may be found on L1973-1976 Sportster frames and does appear to be factory induced.
It has been believed to be for easier access to the motor mount bolt but the threaded area around the right side petcock on the gas tank hangs down close to the bend in the frame.

Click on any pic to enlarge:
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The one frame fits both XLH and XLCH applications.
The left seat post has a “C” channel welded on the lower end for battery tray brackets (threaded holes on upper and lower end, 1 lower for XLH, both for XLCH).
There are 4 squared holes in the middle of the bracket for little plastic expansion nuts (70574-68) used to attach wiring terminals.
These terminals were used for 1970-1972 models for the tail and turn lights before going to plug connectors in 1973.
But with some future year frames sold as replacement for certain older frames, the terminal strip could be used on 70-72 replacement or left alone for newer frames not needing them.
L73-76 frame was suggested as replacement back to 1967 XLH and 1970 XLCH. Click Here to see the main Ironhead frame page for details on replacement frames).

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A service bulletin was issued for SAFETY DEFECT CODE 023, | Click Here to download TSB# 656

All El973 XL and XLCH frames:
Corrective modification was required to prevent possible breakage at the welded junction of the frame tubes and the rear fender and shock absorber support bracket.
Some cases of breakage reported was caused by heavy stress concentration in this location.

In conjunction with this recall program, a further improvement in tail lamp wiring was to be made to correct the short circuit problem originally communicated in TSB# 650.
The rear fender support attaching bolts were to be relocated to raise the fender rear end and provide more clearance between the tire and taillight wires.
(to prevent possible short circuit caused by the tire rubbing through wire insulation under abnormal rear end loading)

A Frame Brace and Fender Support Kit (47420-74) was issued to make these changes. Below are contents of the kit.

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