I recently bought a new frame online but it hasn't shipped yet because I'm having a hard time deciding between two suggested sizes.
My current road bike is a 52 (c-c seat tube; c-t is 55cm approx.). With 55cm c-t and a horizontal top tube, I kind of "seat" on the top tube on the clearance test (very little clearance, 1cm tops, TT actually touches my soft parts if I'm not careful). I slammed the seatpost right down to make it easier for me to climb and start pedalling (I've been riding in the city mostly with frequent stops), but once I'm on the bike I feel the saddle's too low. I guess I've short legs but not THAT short.
I'm also quite lacking in flexibility (I can currently touch my legs about 2-3cm below the kneecaps).
Anyway here are my measurements, taken by someone at a Y's Road bike store in Japan (with a bit of a language barrier between me and the bike fit specialist), all in mm:
Arms: 625 (both)
Height: 1733 (173.3cm)
Inseam: 810 (I measured 800 myself, but I was more careful with said soft bits than the Y's Road gentleman)
They didn't take my "sternal notch" height. :-(
Anyway, here are the specs for two sizes I'm considering for this new frame, please advise which will fit better considering I have 90 and 100mm stems available here and could always get a different size at the LBS, from which, BTW, I won't buy a frame under any circumstances (that's final, I'm having this shipped :-).
"Size 52" Frame "Size 54" frame Seat tube length c-t 490 510 Effective top tube length 537 548 Reach 386 387.1 Stack 526.5 543.1 Head tube length 120 140 Seat tube angle 74º 73.5º Head angle 73 73 Wheelbase 970 976.1
I find these seat tube lengths strange (49cm on a "52" frame and 51cm on a "54"). Both apparently fit me, maybe top tube length is the real question. I don't know. Please help.