What size frame is it?

yamahafx1 said:

Hi. I bought a used frame that was advertised as a 58cm but it appears to be incorrect. It is a 2002 Trek 5200 frame. I bought it to resell so I don't relly care what size it is but I need to find out what size it is so I can sell it. Can someone tell me how to determine what size it is? Thanks

By convention, Trek measures their frames center-to-top (center to bottom bracket to top of seat tube). Some manufacturers measure center-to-center. When you advertise the frame, it would be most helpful to report the top tube measurement or virtual top tube measurement in the case of sloping top tube frames (usually measured center to seat lug to center of head tube along a horizontal line parallel to the ground). This is probably the most critical dimension for fit and allows potential buyers to make comparisons across different brands, models, and geometries.

You can go the Trek website to see diagrams of how they measure their frames.

www.trekbikes.com

While I tend to agree with what John said about top tube length being critical to proper bicycle fit, I think it is bunk in the reality of selling a frame.

I think the vast majority of potential buyers will know what size seat tube they need to avoid damaging their tender parts, but have no idea what their ideal tob tube length should be to ensure proper fit. If they are concerned with top tube length, they probably know what range of seat tube length is likely to be in the right ballpark for them.

I would list the size in the way Trek would (in the title/heading etc), and within the text give both measurements (center-to-center and center-to-top) I would also provide the top tube length (center-to-center) but probably nothing else. I would link to the Trek site with the details (if available) in case the potential buyer is concerned with another measurement.

John M said:

By convention, Trek measures their frames center-to-top (center to bottom bracket to top of seat tube). Some manufacturers measure center-to-center. When you advertise the frame, it would be most helpful to report the top tube measurement or virtual top tube measurement in the case of sloping top tube frames (usually measured center to seat lug to center of head tube along a horizontal line parallel to the ground). This is probably the most critical dimension for fit and allows potential buyers to make comparisons across different brands, models, and geometries.

You can go the Trek website to see diagrams of how they measure their frames.

www.trekbikes.com

Thanks guys.