Yes, that's why I said "with such thin walls." The top of a 753 seat tube has thinner walls than say typical 531, plus the post is thinner, so the OD has to be smaller.
While this all follows logically, I also recall reading that different fittings (lugs BB etc) are required for "metric" tube sets. I aslo recall a friend's Ilkeston 531 bike that had at least one tube that was slightly smaller than normal. The OD of the seat tube was little smaller than normal.
Tom Dalton Bethlehem, PA
LouDeeter@aol.com wrote: In a message dated 7/1/2005 11:29:56 A.M. Eastern Daylight Time, tom_s_dalton@yahoo.com writes: With such thin walls, the 26.8 post sizes imples that the OD was significantly smaller than "normal". I have seen a whole lot more 531 tubes in the imperial size than the smaller, metric size. So, why did they initially offer 753 in the less common O.D.?
Tom, off-list. Not sure why you think the outside diameter is smaller. All 26.8 means is that there is a thicker wall to the normal 1 1/8" outside diameter tube. It is butted from .9 instead of the more common .7 for 27.2. Lou
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