The steering neck is an important but simple part of frame construction. For the typical HD style custom frame, the neck needs to be 5-5/8” tall with a .800” deep counter bore 1.313” in diameter for press in chrome bearing cups. This makes a three-piece assembly (not including races, bearings and dust covers) measuring slightly over 7” tall. The steering axle is typically 1” diameter so the neck needs a 1-1/8 or 1-1/4 through bore.
The neck can be made in one piece at 7.063” tall with counter bores to suit races, bearings and dust covers. It is recommended that wall thickness of .188” is maintained in any cross section of the steering neck and seamless or billet material is used for construction. A cold rolled 1018 steel or 1026 DOM tube works well with typical DOM and CREW mild steel tubing used in custom frame construction.
The drawings
provided below are for reference only.
Skill in metal fabrication, welding and motor vehicle engineering are required
for the construction and installation of these parts. (sorry but for some weird
reason, the “in” got moved into the dimension by the conversion
software…but what do you expect for
free?)
The drawing
below shows a tapered steering neck for press in bearing cups. The outside
tapers can be eliminated and straight walls used in the design.

The drawing
below is for a one piece steering neck where bearing races press directly in
counter bores in the neck itself. It is important that the race used is
measured and it’s bore in the neck is about .0015” smaller to create an
interference fit to keep the race in position. The chrome bearing cups are not
used in this design.
