The Cervelo P5 Unveiled: Simply Faster!

The Union Cycliste Internationale, ruling party of all things bike racing, has been busy "clarifying" rules pertaining to bike design for most of its history. Frames and bike parts deemed legal for years are often found, quite suddenly, to be illegal. Recent victims have included the Specialized Transition, P4 water bottle, Cervelo seatposts, and the much-loved Vision time trial bars.

Growing weary of the changes and restrictions, which strike many as arbitrary and superficial, triathletes have campaigned for bikes that do not adhere to UCI rules, since most triathlons allow for much more design freedom. Bike makers have begun to answer the call. Spy pictures of a UCI-illegal "Illicito" from Quintana Roo have surfaced. Specialized had a brilliant release of the Shiv Tri, with Craig Alexander's Kona win as a fitting introduction. Now Cervelo has released their offering, the P5, which features a UCI-illegal fork, seatpost, and front end. But don't fear, roadies – there's a UCI-legal configuration as well.

Full details on the aerodynamic advancements have not been released yet (a whitepaper is coming) but the Cervelo website hints at the P5 being "30 seconds faster over 40k." It's not known if they are comparing the P5 Tri with the P4, but if so that would represent a significant leap forward, given that the P4 was already among the fastest, if not the fastest, bike on the market. The time savings implies that Cervelo may have trimmed another 75 grams of drag from the P4 to the P5, which would make it a complete outlier among bikes today.



Two Versions - UCI-Legal and Triathlon Specific

The Cervelo P5 frame is a completely UCI-legal and optimized shape. Several design features will appear similar to other recent super bikes such as the Scott Plasma 3 and Cannondale's prototype (currently being referred to as "the new Slice"). This is no accident, as the distinctive seat tube and head tube shapes are a logical consequence of the UCI's tube shape rules. Cervelo claims to have gone the farthest in maximizing these rules, resulting in deeper tube shapes in these regions than any other frame. The UCI-legal frame allows Cervelo to offer the bike in two configurations, one for triathletes and one for roadies. Those with the coin could even switch between configurations depending on the race. The UCI-illegal frameset comes with the following UCI-illegal bits to reduce drag even further:

• A deeper, UCI-illegal fork that integrates with the Magura hydraulic aero brakes
  (~4 seconds per 40k time savings)
• An aerodynamic, UCI-illegal front end cover for the front brakes
  (~3 seconds per 40k time savings)
• A seat post allowing a more forward seat position adjustment
• A custom, UCI-legal integrated aerobar, the 3T Aduro

Given that forks, head tubes, and aerobars sit up front hitting clean air, these changes should make for fairly large drag reductions compared to the UCI-legal frameset. The 3T Aduro offers the most potential advantage with its integrated design, adjustability, and water bottle mounting features. Fortunately, it's UCI legal, so roadies can use it too, though it doesn't come standard on the UCI-legal bike. Below you can see the P5 in three configurations, the standard UCI-legal bike with Magura aero brakes, the UCI-legal bike with a standard brake caliper, and the all-out triathlon setup (click to zoom):

Fit

The P5 frame features a bit more stack than the P3 in order to better accommodate the typical triathlete position. Those who prefer super low positions are not out of luck, however, as Cervelo assures the aero-minded that their 3T Aduro bar in X-Lo configuration allows lower positions than could be achieved on a P3 or P4. They claim the P5 allows more than enough adjustment to accommodate the entire Garmin team's positions, including Aero God Dave Zabriske. Cervelo has provided a stack and reach chart to aid in sorting out their new integrated aerobar system (below). When using the 3T Aduro bar, large stack adjustments are made with the 3 different configurations (X-Lo, Low, High-V). Fine tuning of the stack is done with under-stem spacers shaped to match the integrated stem. These under-stem spacers, once finalized, can not be adjusted much once the fork is cut to size. You can however make adjustments later with armpad riders. Any 3T, or Vision aero arm pad spacers will work.

P5 Features

• BBright - Stiffness and weight +Click For Details
  • Standard on Cervelo's S5 and R series bikes, the P5 is now the first TT bike to be offered with BBright. The BBright bottom bracket takes advantage of otherwise unused space on the non drive side by using an asymmetric shape to increase stiffness and reduce the weight of the frame. Additionally it allows cranksets to improve stiffness and/or weight as the non drive side crank arm can be straighter. In the end, the BB+Crankset system as a whole can be designed stiffer and/or lighter. The P5 will ship with Rotor 3D cranksets, and BBright cranks are currently available from SRAM, FSA, and Tune as well. Many other cranks can be made to work with adapters if desired.
    
• Dropped Down Tube - Integrates with fork and front wheel +Click For Details
  • A feature carried over from the P4 is the dropped down tube. Cervelo combines an integrated fork that fits neatly into the frame and a dropped down tube that hugs closely to the front wheel. The design maintains an airfoil leading edge along this curve around the front wheel, rather than a cutout, which would add drag whenever the wheel is not pointed exactly straight ahead. On the Tri version of the P5, the UCI-illegal fork integrates seamlessly with the aero brakes for a beautifully integrated front end.
    
• Storage and Hydration - Carry water, food, and tools +Click For Details
  • -The P4's integrated water bottle solution proved to not be very popular. The P5 has thus moved to the solution found on the S5, a truncated airfoil shape on the downtube that directs air around your water bottles, reducing the aero penalty of carrying a standard or aero water bottle.
    
    
    
    -The P5 features mounting bolts on the top tube behind the stem, allowing for seamless and secure attachment of accessories of your choice, such as the P5 specific bento box from Dark Speed Works and a very slick, upcoming product from TorHans as well, to be released soon.
    
    
    
    -The P5 offers a "HiddenPocket™" compartment behind the BB to store a Di2 Battery, and could perhaps be used to store a multitool or other small items as well with some modification (though rear wheel removal would be necessary to access it).
    
    
    
    -The 3T Aduro aerobar includes mounts to place a water bottle between your aerobar pads, a hydration solution shown to often reduce drag significantly.
    
    
    
    -A interesting bolt is visible on top of the BB area that may be present to allow integrated flat kit solutions to be mounted. TorHans is working on a product to fit seamlessly into this area, details to come soon.
    
• Magura Hydraulic Brakes - Optimum aero and stopping power +Click For Details
  • This offering is a first for tri bikes. While the P5 will happily accept normal cable actuated brakes, the tri frameset and both complete bike offerings come with the new Magura hydraulic TT brakes. Magura has been building some of the best mountain bike brakes for years. Cervelo worked with Magura to design a road bike brake and brake lever that was as aerodynamic as possible. The hydraulic setup allows for an extremely aerodynamic brake, with all cables hidden from the air, without sacrificing stopping power or modulation. The brakes easily allow new wider rims to fit, offer easy adjustment and quick release, and have a 5 year warranty on fluid loss. Total weight is only 495 grams for the RT8 version, which includes the Cervelo-designed aero brake levers, and fluids. Those who don't wish to use the hydraulic brakes can still use any brake they like, as all mounting points are completely standard.
    
• Easy Maintenance - Easy traveling, wheels fit, standard parts +Click For Details
  • While the front end of the P5 appears very proprietary, the entire bike can use normal parts at all locations. The front brake mount can accept any standard brake, the rear brake can accept standard calipers, and standard stems and aerobars can still be used. Assembly of the bike for travel is perfectly normal and requires no special tools or extra time. The Magura brakes allow for great aerodynamics without the usual difficulty of adjustment and wheel changes associated with center pull brakes. Cervelo also says that all current wheels on the market, including the extra wide wheels from Zipp and HED, fit in the P5 frame.
• The 3T Aduro - Integrated, adjustable, fast +Click For Details
  • Included in the UCI-illegal frameset is the 3T Aduro aerobar. This is available in three configurations (X-Lo, Lo, and High-V), offering a wide range of stack to suit any rider. Cervelo claims that all three configurations are essentially identical aerodynamically, so there is no penalty for those who need more stack. Stack can be fine-tuned with integrated fork spacers, and reach is adjustable in a 5cm range. See the stack and reach chart above in the fit section for details. Cables are routed through the bar completely internally, never seeing the light of day as they enter the frame under the cover of the integrated stem. The Aduro also features a clever bottle mount system, so zip ties are no longer required to "torpedo mount" a bottle between your arms. The Aduro is not included in the UCI-legal bikes, but it is UCI legal, so roadies looking for the fastest setup may want to pick this up too. The X-Lo configuration of the Aduro features a very low stack, which allows for aggressive positions even though the P5 frame stack is higher than the P3 and P4. Cervelo also claims this is the fastest aerobar they have ever tested, and they have tested the much lauded Ventus and USE Tula.
    
    

Specs, Pricing, Availability - ATC expects stock to begin arriving in March

Four configurations of P5 are currently offered, framesets and complete bikes in "TT" and "Tri" configurations. Details and pricing follow:

Trim	Includes	Gruppo	Price
TT Frameset	UCI-legal fork and seatpost, mechanical rear aero brake	N/A	$4,500
TT Complete Bike	3D Rotor BBRight Cranks, 3T Aura Pro Aerobar, Magura Hydraulic Brakes +above	Dura-Ace/Ultegra	$6,000
Tri Frameset	UCI-illegal fork and seatpost, hydraulic brakes, 3T Aduro Aerobar	N/A	$6,500
Tri Complete Bike	Rotor 3D BBRight Crankset +above	Dura Ace Di2	$10,000

More Info

• Cervelo's P5 Official Page
• Cervelo P5 Simply Faster Page
• Slowtwitch P5 Review