Cervelo frames have a very "relaxed" geometry when it comes to the bigger frames. It's the headtube I'm talking about here. :) A size 56 has a 17,3 cm headtube. while most other bikes is around 15,5 or less. And the 58 goes up to a ridiculous 19,9 cm. while others are around 17 cm. Off course every company should do it the way they think is the best. Cervelo don't have to do like anybody else. But...
Why are most pro's I see on Cervelos, using a -17 deg stem on the bigger frames, if the bikes are made for them, and not the average cyclist, who needs a lot more stackheight?
What about shortening the headtube in the bigger sizes. A 56 with a 16 cm headtube, and a 58, with maybe 17,4 and off course continueing in the even bigger sizes?
I'm no framebuilding expert, but I think it's safe to say that a shorter headtuber (which would also lead to a shorter toptube), would shave off more weight. And when the tubes gets shorter, there would be a bit less stress, and therefor the frame would be stiffer (I think :wink: ) But who am I to know. Cervelo got some pretty smart people working on this, so they are most likely right. I just think that it is very weird. And also it looks very stupid. :wink: I think the smaller (cervelo's 54 and under) looks great. And I think the geometri there, is perfect.