I just look at geometry data. Sizes aren't even consistent in one brand. I have a Dengfu FM208 in size 54. I'm looking at an R06. Geometry indicates I should get a size 56 to keep similar stack/reach. It is what it is.

I have a Dengfu FM208 (round tubes + round seatpost) and I want to switch to an R05 (aero tubes + seatpost). I will have the same wheels/tires on both (28mm GP5Ks). I know back in the day aero bikes were way stiffer but is that the case today? My roads aren't terrible but there are definitely some choppy sections and occasional potholes. If they are still super stiff I'd love some suggestions on round seatpost frames with dropped seatstays.

That has some elements but is a little too angular. If that had a vertical seat tube, rounder internal corners in the front triangle and maybe a riser stem I could get on board.

OK to go full Chinese components as well and I'd like to keep the weight down. What's a reasonable weight expectation and what should I focus on? I think I need about 130mm of travel.

I didn't build my Chinese carbon frames/bikes with particularly lightweight components, but I think they turned out pretty light in comparison to my other road bikes.
2018 Chinese S5 replica 17.4 lb.

Man I have been looking for a decent S5 "inspired" frame for a while... what is the make and model?

Here is my build. FM208. I got it down to 6kg/13.2lb with a carbon saddle, 1x drivetrain, tubular wheelset + Tufo S3s. Was awful to ride and slow though, so I put my padded saddle back on, went back to 2x and got some aero wheels + GP5Ks. Glides like a dream now.

WW spec:


Current spec:

Looking for an "aero" rim brake frame and I like these two options. Looking more at them they seem to be the same frame. I've had a great experience with my Dengfu FM208 so I have no qualms getting another Dengfu, hopefully with a cool paint job this time.