I have long been a Cervelo fan boy. I bought two P3 aluminum, two P3Cs, and an SLC-SL over the years and loved them all.
So coming back to the sport, I didn't hesitate to pick up a P5. You can set me straight, but there is a lot that is wrong with this bike:
1) The bottom bracket. This should be renamed "BDim" or "BBWrong"
I bought the P5 used and noticed immediately that the BB was grindy and awful. So I had it replaced in what my LBS described as an excruciating procedure. Here's what the seller (a very big Cervelo dealer) emailed me:
"Press fit bottom brackets (BBs) tend to wear out fairly quickly. Getting even a year out of a pressfit BB is considered a good lifespan...All pressfit bottom brackets need to be hammered out of the frame and can be quite challenging to remove."
So it lasts less than a year and has to be hammered out of the frame! Great design Cervelo! I've had square taper Shimano BBs that lasted for a decade and a Phil Wood one that might outlive me. Now I have a BB that lasts less than a year and costs $50 of labor each time it has to be replaced.
Oh, and I didn't even mention all the problems people have BBright bottom brackets chronic creaking. And I haven't measured the bearing drag, but I would be you're losing at least a watt there.
On its web site, Cervelo claims that "BBright" doesn't change the Q-Factor. That is a half-truth. if you use the Rotor cranks which are dead flat, you get a Q-factor of 153, which is pretty bad already. If you use any other cranks, you end up with a ridiculously wide stance. On the P5, my Cobb cranks yield a Q-factor of nearly 160. For comparison, my Campy cranks on a P3C were only 131. You don't have to be a wind-tunnel genius to know that having your legs 30mm further out is going to increase drag in a major way.
"BBright" has to be the worst bicycle "innovation" I've seen in decades. Even worse than disk brakes on a TT bike. All this BS about better stiffness merely insults our intelligence. The average person riding these bikes is generating maybe 150-250 watts at a cadence of 80-90. Do the math: that is a tiny amount of torque. For TT/triathlon bike design priorities, stiffness should rank about #124. Sacrificing anything for more stiffness is absurd.
2) Hydraulic brakes. It's a TT bike for Chrissakes. You're not going to ride crits with it, so the brakes don't need to be super modulating pieces of high-tech. They need to be easy-to-adjust and easy to swap pads on, so that you can switch from training wheels to carbon wheels easily. These brakes are none of that. Oh and I'd really like to try different aero-bars, but the thought of having to screw with hydraulics definitely nixes that. No Morf bars, no aero-or-die, no U.S.E. Tula. The brakes condemn you to inferior aero bars.
3) The inferior aero bars. I'm probably going to tunnel test these. But one look tells me they're dogs. What a rube-goldbergian design. You actually have to take the whole bar off just to adjust/tighten the extensions. Give me a break.
So, it looks like I'm probably going back to an older vintage P3C. It seems unlikely that the various aero improvements of the P5 would overcome the extra drag of the ridiculous q-factor and the poor aerobars.
My latest book: "Out of the Melting Pot, Into the Fire" is on sale on Amazon and at other online and local booksellers