From a cursory look, seems like most 21.1mm have bmx/mtn sized bar clamps (22.2mm handlebars) while 22.2mm are mostly for classic road bars (31.8mm). Not exclusively though, just seems more commonly done that way.
Nowadays you can get all kinds of bars in 31.8mm or just use some adapter shim if they are 22.2mm. So 21.1mm seems like a legacy standard at this point. 22.2mm bar clamps seem to be out of fashion lately unless it's BMX or some other 'non-competitive' bike design.
It's basically a legacy bmx standard that was entirely abandoned in favour of just using 22,2mm, decades ago.
Luckily apparently the bicycle cruiser people kept using it, so there's like a single factory in china still churning out 21,1mm quill stems that gets sold under 25 different brand names. Sooo...thanks to the most annoying cyclists on earth for that one.
From a cursory look, seems like most 21.1mm have bmx/mtn sized bar clamps (22.2mm handlebars) while 22.2mm are mostly for classic road bars (31.8mm). Not exclusively though, just seems more commonly done that way.
Nowadays you can get all kinds of bars in 31.8mm or just use some adapter shim if they are 22.2mm. So 21.1mm seems like a legacy standard at this point. 22.2mm bar clamps seem to be out of fashion lately unless it's BMX or some other 'non-competitive' bike design.
It's basically a legacy bmx standard that was entirely abandoned in favour of just using 22,2mm, decades ago.
Luckily apparently the bicycle cruiser people kept using it, so there's like a single factory in china still churning out 21,1mm quill stems that gets sold under 25 different brand names. Sooo...thanks to the most annoying cyclists on earth for that one.
:deng-smile:
I thank the chinese people for REDONJI QUILL STEM BICYCLE STEM STEERER STEM METAL ALUMINUM STEEL STEM HANDLEBAR 21,1MM