Greg Parker wrote:
>>>2) Seat post diameter - 753 tubing came in Metric diameters only,
AFAIK, so the seat posts required were generally 26.8 mm (sometimes
27.0) vs. 27.2 mm for 531. (Athough very heavy-gauge 531 frames
sometimes used 26.8 posts, but the weight difference would be even
greater for one of those vs. 753)<<<
I have three frames built with 753 tubing; '89 Merckx Grand Prix, '85 Raleigh Team USA, and '84 custom Trek track frame. Only the Raleigh sports a 753R sticker. Both the Raleigh and the Trek are currently built up with Campy components, the Merckx is not built up, but was my primary ride for many years (and many miles), and I used a Cd'A post. All are currently in storage due to my shop construction project, so I can't go do an in-depth analysis, but I'm pretty confident that all use 27.2 seat posts.
How does that fit into the 753 puzzle?
Wayne Bingham
Lovettsville VA