Cycle Visions Fork Tube Extension For Harley 1997-2017 The Cycle Visions Fork Tube Extensions are constructed from Stainless Steel. Features: Fork Tube Extensions are perfect when installing 23 and 26 front wheels, or to raise your bike up 1 Extends 41mm fork tubes 1 FL models require 2 longer fork slider covers (sold separately) Note: Will not work with air assist or cartridge-style fork tubes.