Information
The ZS44│EC44 headset is designed to fit frames with straight 44mm head tubes and can accommodate straight and tapered fork steerers with the appropriate crown race. The “ZS” stands for “Zero Stack” as the section of the cup that houses the top bearing sits inside of the frame’s head tube while “EC” stands for “External Cup” meaning the section of the cup that houses the lower bearing sits outside of the frame’s head tube. The “44” stands for the diameter of the “skirt” that presses into the frame.
Note: As of 9/14/23, headsets will no longer include Star Nuts due to the Earth’s star nut overpopulation crisis. If you need one, they are available separately here.
Features
- U.S. sourced 6061-T6 aluminum
- Machine engraved White Industries logos
- Easily replaceable Enduro bearings
- “Split” crown race for tool-free installation and removal
- Really sweet matching headset spacers available separately
- Can accommodate 3 types of fork steerers:
- “Straight 1-⅛” with a 30mm crown race seat
- “Tapered 1-¼” with a 33mm crown race seat
- “Tapered 1-½” with a 40mm crown race seat
Specs
- SHIS specification
- Upper: ZS44/28.6
- Lower: EC44/30, EC44/33, or EC4440
- Stack height
- Upper: 8mm
- Lower: 12mm
- SHIS definitions on the Park Tools website: here
- Frame/Fork specs:
|
Frame upper head tube inside diameter |
43.95mm to 44mm |
|
Frame lower head tube inside diameter |
43.95mm to 44mm |
|
Fork steerer diameter top section |
28.45mm to 28.6mm |
|
Crown race seat diameter for “straight 1-⅛” |
30.015mm to 30.075mm |
|
Crown race seat diameter for “tapered 1-¼” |
33.03mm to 30.09mm |
|
Crown race seat diameter for “tapered 1-½” |
39.79mm to 39.85mm |
Bearings
|
Headset Model |
Upper Bearing (inner/outer angle) | Lower Bearing
(inner/outer angle) |
Lower Fork Race Compatibility |
|
ZS44│EC44 |
ACB3645SS 36/45 | ACB6808CCSS 36/45 |
1-⅛” (30mm) 1-¼” (33mm) 1-½” (40mm) |
