Re: Stem tightening, was Re: [CR]The Zen of 7 mm Hex Key stems

Example: History

Date: Tue, 3 Jan 2006 21:23:04 -0800 (PST)
From: Fred Rafael Rednor <>
Subject: Re: Stem tightening, was Re: [CR]The Zen of 7 mm Hex Key stems
In-Reply-To: <>

> Does the 7mm correlate to an SAE size? Actually... no! Amazingly, there isn't really _that_ great a size difference between 1/4 inch and 7mm, yet we see this diversity. This should amuse you:
     I just went down to the dungeon and examined a bunch of old stems (but new enough to use hex keys for the binder bolt) and here are some examples of what I found:
     My oldest Cinelli stem - 7mm
     TTT Gran Prix - 7mm
     TTT Record - 7mm
     Pivo - 7mm for both quill and handlebar binder
     Balleri, "sample #1" - 7mm for quill and 5mm (!)
         for the handlebar binder
     Balleri, "sample #2" - 6mm Everything else, be they French, Italian or Japanese, uses 6mm.
   That includes stems from CTA, Cinelli, TTT, Nitto, SR and a few unmarked pieces.
     So what does this prove? I don't know... but it might answer Peter Kohler's question regarding why MAFAC did not include a 7mm key in their little tool kit. That is, even the bicycle manufacturers might not have known what size key was appropriate on any particular day of the week. But isn't that one of the things what makes these bikes so interesting?
      Fred Rednor - Arlington, Virginia (USA)