If you though bottom brackets were complicated, then you
will love headsets!
Rather than use a third party naming system, I believe the
simplest way to identify what headset you need it just to use the actual
measurements. And the route to finding the correct headset can be reduced to a
few simple questions.
1/ Is the bearing part of the headset internal or external
to the head tube?
2/ Do you have to press cups in to the frame or do the
bearings fit directly in to the headtube?
3/ Is the headtube straight or tapered?
4/ Is the fork steerer tube straight or tapered?
That’s basically it, you have narrowed down the type you
need and if it doesn't give you the answer check the ID of the
headtube and compare it to the poster. Sometimes there will be a new strange headset when a cycle manufacture decided to invent yet another new standard as the ones we already have are obviously not good enough...
Headtube standards measurements
Conventional head tube: Straight traditional headtube with external bearings.
ID = 30mm for 1” steerer tube
ID = 34mm for 1”1/8 steerer tube
ID = 49.57mm for 1.5” steerer tube
 |
| Conventional headset |
Internal
head tube: Often called Zero Stack or Semi-integrated, this head tube takes
press in cups for 1”1/8 steerer tubes or external lower cup for 1”1/8-1.5”
tapered steerer tube.
ID = 41.4mm, economy type for OEM manufacturers.
ID = 44mm, the most common MTB type.
 |
| Internal, zero stack style |
Differential head tubes: Tapered head tubes for press in
cups (internal or external), mostly used on MTB’s.
ID = 44mm upper, 49.57mm lower
ID = 44mm upper, 55mm lower
ID = 44mm upper, 55.96mm lower
 |
| Internal for tapered head tube |
Intellasett head tubes: Press in cups with external cups the same
diameter as the headtube for the integrated look.
ID = 34mm
 |
| Intellaset |
Integrated head tubes: Direct bearing fit in to the frame, the
two most popular types being Cane Creek (36 x 45) and Campagnolo (45 x 45).
ID = 41mm, 1”1/8 with 45 degree bearing seat (CC 36x45). *Upper seat can be 2.7mm
or 3.2mm deep
ID = 41.7mm, 1”1/8 with 36 degree bearing seat (TH 36x36)
ID = 42mm, 1”1/8 with 45 degree bearing seat(Campy 45x45)
ID = 47mm, with 45 degree bearing seat 1”1/4 straight
 |
| Integrated headset |
Differential Integrated head tubes: Direct
bearing fit in to the frame for tapered head tubes.
ID = 42mm upper with 45 degree bearing seat, 52.10mm lower with 45 degree
bearing seat. For 1”1/8-1.5” tapered steerer tube.
ID = 41.2mm upper with 45 degree bearing seat, 49.1mm lower with 45 degree
bearing seat. For 1”1/8-1”3/8 tapered steerer tube
ID = 42mm upper with 45 degree bearing seat, 47mm lower with 45 degree bearing
seat. For 1”1/8-1”1/4 tapered steerer tube
ID = 42mm upper x 6.5mm deep with 45 degree bearing seat, 47.1mm lower x 6.5mm deep with 45 degree bearing seat for 1"1/8 - 1" 1/4 steerer. NEW Overdrive system.
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| Integrated headset for tapered head tube |
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| all you need to know! |
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| 1"1/8 to 1"3/8 tapered headtube |
