• CM was "always" 27.2mm.
    Only exceptions were 70cm frame and ladies kruisframe => 26.4mm
    Maybe a very old, exceptional 753 had 27.0mm, but I'm not sure of that.

    All Formulas en Trophies had 26.4mm.
    At least all the ones with 531 pg tubing.
    Don't know about 501 and 525 tubes (1990's) ?

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