School me on stem quill sizes
02-06-11 | 06:32 PM
#1
Thread Starter
Senior Member
Joined: Aug 2008
Posts: 4,134
Likes: 192
From: Somerville, MA and Catskill Mtns
School me on stem quill sizes
Okay, 22.2mm is the Japanese/international standard. 22.0mm was the French standard. What else was out there? I have a vintage GB stem that my caliper is measuring at 21.0mm. Was there such a standard? Clamp diameter is 25.4mm.
It also looks like someone used it at some point in a standard 22/22.2 steerer because the split is flared out to ~22mm by the expansion bolt.
It also looks like someone used it at some point in a standard 22/22.2 steerer because the split is flared out to ~22mm by the expansion bolt.
02-06-11 | 06:43 PM
#2
Okay, 22.2mm is the Japanese/international standard. 22.0mm was the French standard. What else was out there? I have a vintage GB stem that my caliper is measuring at 21.0mm. Was there such a standard? Clamp diameter is 25.4mm.
It also looks like someone used it at some point in a standard 22/22.2 steerer because the split is flared out to ~22mm by the expansion bolt.
It also looks like someone used it at some point in a standard 22/22.2 steerer because the split is flared out to ~22mm by the expansion bolt.
Last edited by unworthy1; 02-06-11 at 06:50 PM.
02-06-11 | 08:07 PM
#4
Bike Junkie
Joined: Jun 2005
Posts: 9,625
Likes: 40
From: South of Raleigh, North of New Hill, East of Harris Lake, NC
Bikes: Specialized Tarmac, Specialized Roubaix, Giant OCR-C, Specialized Stumpjumper FSR, Stumpjumper Comp, 88 & 92Nishiki Ariel, 87 Centurion Ironman, 92 Paramount, 84 Nishiki Medalist
In addition to the 21.1 I believe there is a 21.0 on some 70's Peugeots.
__________________
Roccobike BF Official Thread Terminator
Roccobike BF Official Thread Terminator
02-07-11 | 06:03 AM
#6
Old Skeptic
Joined: Jan 2006
Posts: 1,044
Likes: 9
From: New Mexico, USA
Bikes: 19 road bikes & 1 Track bike
The GB brand was commonly used by Schwinn during the 1970s for many road bikes, but usually their logo "GB" (in a circle along the extension) was substituted for the letter "S" for the Schwinn commissioned stems. And Schwinn had adopted that odd steering tube diameter for a while.
I also have a chrome plated Tange 27" replacement fork which was reamed to that diameter, and a French made "AVA" alloy stem in the same diameter which I'd found with that fork. That French stem was NOT later milled down, it was factory cast with that diameter below the top 2 1/2 inches (and the top portion of the quill is 23.0 mm - not the standard 22.0 French size). Much like Taiwanese parts today, French stems were once VERY inexpensive in the US, so they too were bought up by many big US manufacturers for lots of lower level domestic bikes.
I also have a chrome plated Tange 27" replacement fork which was reamed to that diameter, and a French made "AVA" alloy stem in the same diameter which I'd found with that fork. That French stem was NOT later milled down, it was factory cast with that diameter below the top 2 1/2 inches (and the top portion of the quill is 23.0 mm - not the standard 22.0 French size). Much like Taiwanese parts today, French stems were once VERY inexpensive in the US, so they too were bought up by many big US manufacturers for lots of lower level domestic bikes.
03-20-16 | 05:31 AM
#7
Senior Member
Joined: Feb 2004
Posts: 7,176
Likes: 56
From: Clev Oh
Bikes: Specialized, Schwinn
I've always heard .833 referred to as 21.1 older Schwinns, BMX and some early MTBs used that size. I have a nice MTB fork with U-brake mounts that takes a 21.1 stem. Ebay is a good source of stems if you need one.
03-20-16 | 03:16 PM
#8
Senior Member
Joined: Jan 2006
Posts: 6,567
Likes: 1,065
From: Berwyn PA
Bikes: I hate bikes!
03-20-16 | 05:40 PM
#10
Bikes are okay, I guess.
Joined: Jan 2015
Posts: 8,063
Likes: 3,828
From: Richmond, Virginia
Bikes: Waterford Paramount Touring, Raleigh Sports 3-speeds in M23 & L23, Schwinn Cimarron oddball build, Marin Palisades Trail dropbar conversion, Nishiki Cresta GT, Jeunet mixte
Since it's back I'll chime in. Just found some old stems in my hoard of stuff, including one of those nice "S" branded GB stems. The standard non-metric measurement for those is .833 inch diameter and this one is stamped as such; it is only the equivalent of 21.1 metric.
Rather like those modern guys who refer to seatpost diameters at 27 dot 2 when it is actually a decimal point, not a dot.
Rather like those modern guys who refer to seatpost diameters at 27 dot 2 when it is actually a decimal point, not a dot.
Thread
Thread Starter
Forum
Replies
Last Post
Cheseldine
Bicycle Mechanics
22
09-12-24 08:30 AM
