Cyclocross frame Sizing Help?

Triathlon Forum
1

Hello all,

I was hoping someone with some cyclocross experience could give some input re: frame sizing. The frame i was considering comes in either a 49cm or 52cm size with a 52.5 & 54.2 top tube, respectively. I typically ride a 51-52cm roadframe with anywhere from a 52-53cm TT. Should I strictly look at top tube length in sizing a cross frame? Based on the geometry/specs, the 49 seems to be the right choice but wanted to make sure since it is quite a bit smaller than my “road size”. Also, the 54.2 TT on 52cm seems a bit big for me. For reference, I am about 5’8" tall with a 30.5 inseam. I ride a 52cm KM40 tribike that fits perfect. Any input would be much appreciated- thanks!

2

Generally, a cross frame is sized a little shorter thru the toptube, a little taller at the handlebar, with a little extra stand over clearance than a road frame. From the few numbers you provided, the 49 would seem to be a better choice than the 52.

3

Ditto.

Go smaller…and you’ll probably have to raise the stem slightly for CX races.