Note: As the White Industries catalogue is diverse, we don't stock every variant or colour. However, we place regular airfreight orders. If an item is in stock at White Industries, we can usually have it here within a week. Even if it's not in stock, they can often assemble it for us, and we can have it within three weeks at most. Feel free to get in touch if you're after something specific!

The IS41│IS52 headset is designed to fit frames with integrated 41mm/52mm head tubes and works with tapered and straight fork steerers. The “IS” stands for “Integrated” as the bearing sits directly inside the frame’s head tube without a cup. The “41/52” stands for the top/bottom inside diameter of the frame’s head tube. 

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.

Features

• U.S. sourced 6061-T6 aluminum

• Machine engraved White Industries logos 

• Easily replaceable 440C Stainless Steel Enduro bearings which feature a limited lifetime warranty

• “Split” crown race for tool-free installation and removal

• Really sweet matching headset spacers available separately

• Can accommodate 3 types of fork steerers:
  
  
  • “Straight” 1-1/8″ with a 30mm crown race
  
  
  • “Tapered 1-¼” with a 33mm crown race seat
  
  
  • “Tapered 1-1/2” with a 40mm crown race seat

Specs 

• SHIS specification
  
  
  • Upper: IS41/28.6
  
  
  • Lower: IS52/33 or IS5240
  
  

• Stack height
  
  
  • Upper: 8mm
  
  
  • Lower: 1mm
  
  45 degree outer contact angle

• SHIS definitions on the Park Tools website: here

• Frame/Fork specs:

Frame upper head tube inside diameter	41.10mm to 41.2mm with a 45 degree contact angle
Frame lower head tube inside diameter	52.05mm to 52.15mm with a 45 degree contact angle
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 1-1/4”	33.03mm to 33.09mm
Crown race seat diameter for “tapered 1-1/2”	39.79mm to 39.85mm

Bearings

Headset Model	Upper Bearing (inner/outer angle)	Lower Bearing (inner/outer angle)	Lower Fork Race Compatibility
IS41│IS52	ACB3645SS 36/45	ACB6808CCSS 36/45	1-⅛” (30mm)  1-¼” (33mm)  1-½” (40mm)