Originally Posted by
roadwarrior
http://www.twothirds.org/caad4-geometry.pdf
The 4 and 5 had the same geometry. The biggest difference was that the 5 was the first integrated headset frame for Cannondale. No issues. It was a pro frame as your photo shows. The bike before it the CAAD4 was the first "hourglass seat stay" bike. Probably a 2003 if I recall. The chart I linked has a 2006 on it, but that was from the archive, not the frame date.
There was a short lived CAAD6 then the really lightened up the frame with the Optimo CAAD7.
Great. Thanks very much. However, unfortunately, that chart doesn't seem to have head tube sizes, which is one thing I'm particular about, coz of my dodgy back
I found what I think is a track chart, which says the 56 has a 168mm head tube; what does this mean?