Frame sizing

the_urban_spaceman

Hi.

It's my understanding to size down slightly with a cross bike, however I have been told that some manufacturers take this into account and therefore will make (say) a 54cm that's actually a 52.

Is that really correct? It seems like a good way to over-complicate things

drlodge

A "54cm" frame means nothing. Best to look at the frame geometry chart and see exactly what lengths and angles the various bits of the frame are.

the_urban_spaceman

drlodge wrote:

A "54cm" frame means nothing. Best to look at the frame geometry chart and see exactly what lengths and angles the various bits of the frame are.

But is a frame listed as 54cm (bb to top seat tube) actually 54? Or is it shorter to take account of it being a cross bike.

Appreciate it's a stupid question but it's based on what I've been told by a professional bike fitter!

drlodge

the_urban_spaceman wrote:

drlodge wrote:

A "54cm" frame means nothing. Best to look at the frame geometry chart and see exactly what lengths and angles the various bits of the frame are.

But is a frame listed as 54cm (bb to top seat tube) actually 54? Or is it shorter to take account of it being a cross bike.

Appreciate it's a stupid question but it's based on what I've been told by a professional bike fitter!

As I said, "54" means nothing. You have to look at the geometry chart for the frame.

A frame that's listed as a 54 almost certainly won't be 54cm bb to top seat tube, it'll be somewhat less than that. Hence the 54 means nothing. Its likely to have something around a 54cm effective top tube length, give or take.

the_urban_spaceman

OK thanks.