Step 3: Find a Matching Head Tube
You will also require a head tube that will match the length of the fork stem. A matching head tube will be about 2 inches shorter than the fork stem to allow all of the bearing hardware to install properly. If the head tube is too long, you can always cut off a section, and may also be able to cut a bit of the threaded fork stem if it is too long. I hacked an old mountain bike frame from the head tube shown in Figure 3, and it looked to be about the right length to match.