Headtube Guide

General Information

  • We manufacture straight and tapered headtubes in titanium and steel
  • Our decision to manufacture a given standard will be based on its anticipated applications and longevity in the market

Selecting the Right Headtube

1. Select the fork that you will be using, consider:

  • Headset type
  • Steerer tube diameter
  • Steerer tube length
  • Wheel size and brake type
  • Axle-to-crown length

2. Select a compatible headtube

3. Select a headset

4. Questions? Consult your frame builder!

Resources

44 mm Straight Headtube

44 mm Headtube

Reamer/Facer:  44 mm

 

Fits Steerers:

  • 1.125”
  • 1.125” - 1.250”
  • 1.125” - 1.500”

Available Materials:

  • 3/2.5 titanium
  • 4130 steel

EC34/EC44 mm Tapered Headtube

HeadtubeInformation:

  • “EC” stands for “External Cup”, meaning the section of the cup that houses the bearing sits outside of the frame’s head tube
  • ”37” (top/bottom) stands for the diameter of the “skirt” that presses into the frame

Reamer/Facer:  44 mm and 1.250"

Fits Steerers:

  • 1.125”
  • 1.125” - 1.250”
  • 1.125” - 1.500”

Compatibility:

  • 1.125" EC
  • 44 mm EC + ZS headset

Available Material: 4130 Steel

IS41/IS47 mm Tapered Headtube

IS41/IS47

Information:

  • Works with tapered and straight fork steerers

  • “IS” stands for “Integrated” as the bearing sits directly inside the frame’s head tube without a cup

  • “41/47” stands for the top/bottom inside diameter

Reamer/Facer:  41 mm IS and 47 mm IS

Fits Steerers:  1.125” - 1.250”

Compatibility:  IS41 and IS47 mm headset, such as 110.IS41 top and 110.IS41 bottom

Available Material:  Titanium

IS41/IS2 mm Tapered Headtube

IS41/IS52

Information:

  • Works with tapered and straight fork steerers
  • “IS” stands for “Integrated” as the bearing sits directly inside the frame’s head tube without a cup
  • “41/52” stands for the top/bottom inside diameter

Reamer:  41 mm IS and 52 mm IS

Facer:  41 mm IS and 52 mm IS

Fits Steerers:  1.125” - 1.500”

Compatibility:  IS41 and IS52 mm headset, such as 110.IS41 top and 110.IS52 bottom

Available Material:  Steel

EC37/EC37 mm Tapered Headtube

Headtube

Information:

  • “EC” stands for “External Cup”, meaning the section of the cup that houses the bearing sits outside of the frame’s head tube
  • ”37” (top/bottom) stands for the diameter of the “skirt” that presses into the frame

Reamer/Facer:  37 mm EC

Fits Steerers:  1.125” - 1.250”

Compatibility:  IS37 mm headset

Available Material:  Steel

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