Bike Forums - View Single Post - Understanding Headset Specs
View Single Post
Old 03-11-18, 12:23 PM
Senior Member
Kontact's Avatar
Join Date: Apr 2011
Posts: 3,595
Mentioned: 32 Post(s)
Tagged: 0 Thread(s)
Quoted: 2146 Post(s)
Likes: 0
Liked 6 Times in 6 Posts
Originally Posted by Quiglesnbits View Post

I am on a quest to understand headset nomenclature and specs, and I ran into a frame with a Headset spec listing that has me confused.

It says "1-1/8", tapered, IS 47/33". From reading a few articles, it seems like the IS47/33 is a lower bearing spec for a 1-1/4" tapered fork, but I am unsure how to know what upper bearing would work on this frame. Is 1-1/8" a pretty standard upper bearing size? Do I not need to know any other bore sizes, angles or anything else? To my untrained eye, this doesn't seem like enough information. Can you help me understand what I am missing?
That is not a complete headset spec - though it probably is such a common spec that it is used on quite a few bikes. But you would likely need to measure some things on the frame before you bought a headset.

This is a good tool to understand headsets:

Do you need to know that spec? Usually framesets with integrated headset bearings come with all the parts.
Kontact is offline