the perfect geometry for Disc

[jerome]

I am looking to have build a new disc bike.
I would like it very versitile a bit like a Specialized Roubaix and a CX.

what would be the perfect geometry for you ?

last cal

[Louis]

Salut Jerome !

For me this raises the following question:

Should one start with the fact that one wants to use disk brakes and design the frame geometry around that, or should one design the frame geometry around the rider and the intended bike use, then modify that design to accommodate disk brakes?

I would think that the second approach would be better. Are local stay and fork modifications enough to handle disk brakes, or would the required changes be significant enough to modify the rest of the frame design?

(I ask these questions from ignorance, not from a position of knowledge.)

Best of luck with your project.

[tigoat]

Not sure what you are asking about but a Specialized Roubaix is not a CX bike. A Roubaix has a long head tube but with a normal road fork while a CX bike has a much taller and wider fork so the head tube must be shorter in most cases. A CX bike usually feels tall when you ride it on the road. A Roubaix as well as others like the Volagi is consider to be an endurance bike, a new class of comfort road bikes. Unless you want to use big tires above 28 mm, a Roubaix or a Volagi is a very nice road bike to have with disc brakes.