V-Twin Mfg Neck Cup Conversion Kit 7/8 Inch to 1 Inch Ironhead for Harley-Davidson Sportster
Early Ironhead Sportster and 45 cubic inch frames running a 7/8 inch neck stem can accept a 1 inch fork assembly once these conversion cups are pressed in. It’s a clean path to running a Big Twin or late Sportster fork on a period frame.
Key Features
- Converts 7/8 inch neck stem frames to accept 1 inch neck stem fork assemblies
- Includes cups and tapered bearings for 1 inch fork stems
- Fits early Sportsters and 45 cubic inch frames originally equipped with 7/8 inch stems
Technical Specifications
- Converts: 7/8 inch neck cup to 1 inch neck stem
- Includes: Conversion cups and tapered bearings
- Note: Order related spacers and nuts separately
Fitment Notes
- For early Ironhead Sportster models and 45 cubic inch frames originally using 7/8 inch fork stems
- Remove existing cups and install these into the frame neck before fitting any 1 inch stem fork assembly
- Spacers can be installed on the underside of the neck for added height – order related spacers and nuts separately







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