Cyclocross frame size vs. road bike frame size I'm in the market for a used cyclocross bike to use as a winter bike, and so I've been browsing craigslist.  I generally ride a 56-58 cm road bike frame, so I turned down an otherwise good deal because it was a 52 cm frame.  The seller told me that a 52 cm cyclocross frame was comparable to a 54 cm road frame.

Is that statement true?  And if it is true, how is that so?
Bicycle sizing may vary by bicycle type, region, manufacturer, and material. And measurements typically are of a length of the frame (usually bottom bracket to top tube: How do I measure the size of my bicycle frame?). So it would not be surprising if this statement was true.

Depending on the geometry of the frames, two bikes may have different "sizes" but actually fit the same size rider well. It is possible that cyclocross frames tend to have a smaller measured sized.

Here is a post that goes in depth... and is ultimately inconclusive: http://www.bikeforums.net/archive/index.php/t-138316.html