Cervelo P3C

The new standard - Just like the P3 took the time trial and triathlon world by storm, so has the P3C. Victorious in roughly half of the ProTour TTs in which it has been entered and equally successful in Ironman Triathlons, the P3C is the reference for the time trial bike market.

Aero headtube - no bulky nose cone, but an extremely thin, aerodynamically optimized shape

CCS - Constant Cross-section Seattube - The airflow over the seattube is predominantly horizontal. The new seattube shape has a cross section shape that is separately optimized everywhere between bottom bracket and the seatstay joint.

New Cervélo aero carbon IAA seatpost - With its Integrated Accessory Attachment, this new seatpost can secure behind-the-seat components such as water bottle holders much more securely. Expect new products for the IAA system soon.

Integrated Seattube collar - By integrating the seattube collar completely into the toptube, we are able to smoothen the aerodynamic profile even further. The airflow doesn't even see the collar, yet the seatpost can be removed with ease. By integrating the seatpost into the frame aerodynamically but not structurally, you can fit the P3C into any bike case and travel without a problem, something that is very difficult to do with other integrated seatpost solutions that have the seatpost molded into the frame in one piece and that do not allow for the seatpost to be removed.

And we certainly have first-hand experience with this, as the original Cervélo P2 was the first bike to sport an integrated seatpost that was permanently attached to the frame. While it was the best solution we could come up with back in 1996, the new system with the removable seatpost is superior not only for traveling but also aerodynamically, as it allows us to use a much narrower seatpost than if it was a structural part of the frame.

ICS Internal Cable Stops - The best internal cable stop system available. Easy to install, easy to service, easy to keep clean and improved aerodynamics.

UCI legal - As with all our frames, the P3C is UCI legal

Frameset - The P3C is also available as a frameset

More aero seattube - The curved seattube covers more of the rearwheel than any other cutout, resulting in even better aerodynamics.

When Cervélo first started using tube profiles as designed by the National Advisory Committee on Aeronautics (NACA), it caused quite a stir in the bike industry. These tubeshapes are the result of years and years of research and do a very good job of reducing the aerodynamic drag created by the tubes. We manufactured extrusion dies specifically for these NACA profiles, as it was the only way to get the tube shapes accurate.

But while NACA profiles are good, they are not ideal for bicycles. NACA profiles are generally designed for higher speeds, even those designed for "low-speeds" were made with speeds in mind that go beyond most cyclists' abilities. Therefore we have turned our attention to designing our own airfoils at Cervélo in the past few years, improving wherever possible on the foundation laid by NACA. The result is the latest family of airfoils, from the shapes used on the Soloist, Dual and P series TT/Tri bikes to the Wolf shapes optimized for frame and fork shapes adjacent to spinning wheels.

The tube shapes and aspect ratios on the P2C and P3C are a little different than on the Aluminum frames, which together with the other aerodynamic improvements (cutout, headtube, etc) accounts for the improved aerodynamic performance.

Effective toptube length - Traditionally the toptube length is pretty easily defined as the length of the toptube from headtube to seattube. But what if that seattube is curved? In the drawing you can see three frames that obviously fit the rider the exact same way, yet if the toptube was measured the traditional way they would seem very different. Dimension A, the effective toptube length, is the only useful and necessary toptube measurement for the P3C. The black frame in the first image is the "straight seattube equivalent" of the grey P3C. This dimension A is listed in the tables below, and you can compare it back and forth with any other frame's geometry without any problem. Dimension B has no relevance in fitting; it is merely the physical length of the toptube in this particular construction. By the same token, one could construct a 90 degree seattube angle and a super setback post to get a very short physical toptube (dimension C), but obviously the effective toptube length of such a frame is still dimension A, not dimension C.

Bottom line: use the toptube lengths from the tables below and the frame will fit you exactly as expected. Don't get confused by people trying to make this more difficult than it is.

Seattube lengths vs. frame size - The discrepancy between seattube lengths and frame size this is merely the result of evolution. Traditionally road bikes had seattubes the same length as the frame size (so a 54cm frame had a 54cm seattube.) There might be some inconsistency as to whether the seattube was to be measured from the center of the bottom bracket to the center of the toptube, or to the top of the toptube, or to the top of the seattube, but other than that this system was foolproof.

But with the advent of time trial-specific frames, things got complicated. To get low enough, people needed shorter headtubes. So the first sloping frames appeared, but they were sloping from high at the seattube to low at the headtube. This way the headtube was short while the seattube kept its traditional frame size measurement intact. Soon frame builders recognized that making a sloping toptube just to make it easy to measure a frame was silly, so they reverted back to horizontal toptubes with just a seattube extension to the original seattube length (as indicated by the frame size). While this is where things stayed for most manufacturers, Cervélo realized two things:

1. The extension served no structural purpose; it was just there so that people could measure the frame size. We figured a size decal would do the same.
2. Customers often would only insert the seatpost into the seattube extension, and not all the way past the seattube-toptube cluster. This would put undue stress on the welds and could potentially lead to cracks.

So Cervélo decided to eliminate the seattube extension, thereby eliminating this risk of frame failure. The frame size is still easily determined with the size decal (easier than finding a tape measure) or alternatively, one can measure the headtube and look it up in the geometry chart.

Hopefully this clears up any confusion that may have arisen, if you still have questions (or find a bike shop that does not quite understand the above), please contact us and we’d be glad to elaborate.

With regards to seattube angles, 77-78 degree seattube angles have become more and more common for time trial and triathlon bikes in the past few years. Whereas in the past time trialers often rode at more shallow angles in the 74-75 degree range, the situation is no longer as lopsided. Riders like Zabriskie, Basso and many of their Team CSC colleagues now ride at 77-78 degrees, and if it weren’t for the restrictive UCI rules on saddle position, some might even ride steeper. Other teams are starting to catch on to this trend as well, and no wonder if you look at the results Team CSC garners in time trials.

But even if you aren’t a professional cyclist, there are compelling reasons to ride steep on a time trial bike:

1. With lower back flexibility often a limiting factor, a steep seattube angle allows you to attain a flatter back without having to change your body’s “internal” angles (hip angle, knee angle, etc). Basically, a steeper seattube angle rotates the rider forward around the bottom bracket, thereby leaving the internal angles intact while positioning the back more horizontal.
2. A steeper seattube angle can allow you to even open up your hip angle, thereby reducing the strain on your lower back as well as making the pedal motion less restrictive.
3. For triathletes, several studies have shown that running times after riding a bike decrease if the bike was ridden with a steep seattube angle.

That said, a steep seattube angle is not for everybody and it remains a personal preference, so we offer our TT/tri bikes with adjustable geometry, allowing for an effective seattube angle anywhere in the 74-79 degree range.

Note that we say effective seattube angle, as the standard seattube angle is really a very inadequate dimension. It does not describe very well the position of the point that actually matters for fitting, the saddle. A 75 degree seattube angle with a large setback seatpost and the saddle pushed backwards is a lot less steep than the same seattube angle with a zero-offset post and the saddle forward. The variation between these two situations can be as much as 3 degrees, yet both are called 75 degree seattube angles. So to really be able to intelligently compare positions, it is better to use effective seattube angles, which is normalized for a standard seatpost setback and a saddle position in the middle of the range. In the example above, we would call the first situation an effective seattube angle of 74 degrees, and the second situation an effective seattube angle of 77 degrees. In other words, you can achieve the same position for the saddle (and therefore the rider) with different seattube angles, as long as the seatpost and saddle position are adjusted to create the same effective seattube angle.

You will see that changing the effective seattube angle actually does change the effective toptube length even though the physical toptube length obviously doesn't change. This is easily understood when you realize that when you change the seat post clamp from the rearward to the forward position, you steepen the seattube of the "straight seattube frame equivalent" from the original slack frame (the black frame in the second image above left) to the steeper grey frame in that image without moving the headtube, so the toptube length shortens from dimension A to dimension D. The Cervélo frame geometry is such that in both situations, the toptube length is correct for riding is that position, as time trialers with a shallow seattube angle generally need a longer toptube than if they ride in a forward position.

In the geometry tables below we list the dimensions for 75 and 78 degree effective seattube angles, roughly corresponding to the two positions of the adjustable seatposts if the saddle is clamped in the center of the rails.

During the development of the P2 and P3 models, Cervélo has ensured that these models comply with the new UCI regulations that came into effect on January 1, 2000. The main points of the new rules are:

1. Frames have to be of a double diamond lay-out
2. Both wheels have to be the same size
3. All tubes have to fit within a 80mm wide template, except near the joints where more room is allowed
4. A credit card has to fit between the seattube and the tire. Don't jam it through, as the official may not try that either. Just play it safe, and if there is any trouble sliding the credit card through, move the wheel a millimeter further back. A 3mm gap will enable a credit card to slip through without a problem (2.1mm should do it theoretically). The horizontal drop-outs of our TT bikes enable the rider to achieve the appropriate gap irrespective of the size of tire used.

Several national federations are working on a grace period so that people with old bikes can still compete in events. But this grace period will likely only apply to bikes purchased before January 1, 2000, so if you are looking to buy a new bike, please ensure that your bike is approved by the UCI. And for more information on a grace period, contact your own national federation.

The link below will show you the UCI approval of our models. To make sure things go smoothly at the pre-race technical inspection, you can print this out and present it to the commissaires. Be sure to print it in grayscale and high quality for proper reproduction of the drawings. Click here to view the UCI approval