above: highly adjustable, and with aero cable integration,
the P5D's front end is very neat
The main thing that attracted me to the new P5D was the front
end; the whole thing is based on a monoriser; and it simply
requires a 4mm Allen key to raise or lower it. To me this is
genius; and a huge competitive advantage over more fiddly
Above 30 mph, 90% of the energy the rider generates is used to
move air out the way (drag). And of this drag, 70% of it is created
by the rider... So an aero position is incredibly important
Lowering the front end of the bike can sometimes get you lower -
present a smaller frontal area and you become faster.
However sometimes if you get too low you close off your hip
angle, making it hard to put power down (an easy way to check this
is to see the difference in 10 min power you can produce on a road
bike versus a TT one. Anything more than 10% means your TT position
either needs a lot more adaptation or, more likely, needs to be
So playing around with the front end is so important; and in the
past it took ages to swap spacers around and re-cable the bike; so
you'd be much less inclined to tinker around with position.
The Cervélo monoriser is genius - it makes adjusting the front
end position as easy as adjusting as your seatpost and I hope more
big brands copy this idea. But in the meantime, it's a definite
plus point for Cervélo.
The only thing I don't like is the fact that the extensions are
a proprietary monostay design and that they don't tilt. I like my
extensions quite high (in the "praying mantis" position) and find
these are too low.
However, there is a work-around in that you can swap the
extensions designed for the Cervelo P3X with those intended for the
P5D, giving you the best of both worlds.