In article ,
Artoi wrote:

With Paris-Roubaix, everyone's talking about the value of "relaxed"
frame geometry again, specifically the long head tube and the
benefits they bring.

My question is, what ride differences are there b/n a frame with a
longer head tube and a regular road frame that has more spacers
inserted below the stem, thereby achieving a longer virtual head
tube?

I've asked this question a number of times elsewhere and no one
seemed to be able to answer it directly. --

It's hard to answer because it doesn't entirely make sense, especially
since I haven't seen any of these discussions about "relaxed" frame
geometry, long head tubes, etc. IMHO the benefit is making the bike fit
your particular dimensions for your particular purpose. At 6'4" and 215
pounds, I ride bikes ranging from 60 cm to 64 cm center-to-top. One has
"laid back" geometry (72/72), one has "neutral" geometry (73/73.5) and
one has a mix (74/72.5) (all parenthetical angles are head/seat tube).

Do I notice a huge difference switching from bike to bike. No, and what
difference I notice is only for about a minute when I start riding.

In terms of fit, it's easiest to get the tallest of the bikes adjusted
to fit me comfortably. The smaller frames make it hard to get the bars
up high enough to be comfortable on long rides (about 2 cm below the
saddle). I have stems with long quills as a result and they look a
little odd. Back when I raced I had the bars 6-8 cm below the saddle
for aerodynamics and the smaller frames made that easier to achieve.

Paris-Roubaix is an unrealistic yardstick. Few of us spend our days
hurtling as fast as we can across ancient cobblestones covered in
manure. Most of us might ride on a gravel road or have to contend with
the failing American infrastructure bequeathed to us by nearly three
decades of anti-government anti-tax arrant nonsense. Fatter tires would
be a better investment than relaxed geometry and long head tubes...