This is the "500EX Key Hub". It is a slightly different version of the 500 Key Hub. It is manufactured differently, as it is extruded. Also, there is a 1.124" diameter boss on each side of the hub flange, providing a location for 1.125" bore flat sprockets. Are you having a hard time keeping your sprocket concentric with your hub? This hub is the trick.
The bore is a 1/2" hole with two 1/8" keyways. Only one keyway is needed to drive most wheels, so the second one is extra.
This hub fits all AndyMark wheels.
Also, the keyways are consistently aligned with the mounting holes.
- Material: 6063 Aluminum
- Bore: 0.502-508" diameter bore, with 1/8" keyway (2)
- Bolt Pattern: 0.204" diameter holes, evenly spaced on a 1.875" diameter bolt circle
- Outside diameter: 2.25"
- Weight: 0.1 pound
This part is designed and made in Indiana, USA.