| Features | BBStop
BBstop’s design incorporates a stop in our Single-Bend bottom bracket guide, permitting use of cable housing through the down tube.
With the increasing prevalence of electronic controls, the permanently bonded-in ICS3 guide tubes are no longer required for proper shifting performance. Leaving them out simplifies electronic installation and saves weight.
However, since many riders still prefer mechanical shifting, we've simply engineered BBstop to accommodate all options in a single design. BBstop’s design incorporates a stop in our Single-Bend bottom bracket guide, permitting use of cable housing through the down tube. This stop prevents housing shift (fore-and-aft), fixing the axial position of the housing where it enters and exits the frame for consistent bend radii. Both ICS3 and BBstop models are simultaneously compatible with mechanical, electronic and hydraulic controls.
Extended Seat Tube Cutout
Maximized extended cutout that smoothes airflow from frame to wheel, yeilding one of the largest single reductions in aerodynamic drag.
By shielding the spinning wheel from the wind, the cutout yields one of the largest single reductions in aerodynamic drag. The concept is inherently intuitive, however, executing the design requires true aerodynamic expertise.
In order to most effectively reduce drag, the cut out must have the right curvature and width to take full advantage of contemporary aerodynamic wheel technology. The result is that the wheel is completely shielded while maintaining its own aerodynamic advantages. We incorporate this knowledge on every Cervélo model with a rear wheel cutout.
On some Cervélos, the cutout is extended upward to be even more effective; covering the top of the wheel is particularly important, as it moves forward at twice the riding speed. Yet even on Cervélos that don’t have this extended rear wheel coverage, the seat tube width and shape is engineered to be an aerodynamic match with the tire and wheel along the cutout’s entire height, even changing the seat tube’s cross section where necessary.
Dropped Downtube
Positioning the down tube perfectly saves drag on the system by taking into account the interaction between the front wheel and the frame.
We’ve always engineered our aero bikes using the lowest drag tube shapes we know of. But the lowest drag bike is more than low drag tube shapes. During the years we spent developing the P4, we also considered the aero interaction of the various tubes with other parts of the bike. The result is Cervélo’s AeroZone engineering principle.
The downtube AeroZone includes nearby components, such as the front brake, fork and wheel. Dropping the down tube “hides” the down tube in dirty air, reducing the high pressure normally found on the down tube’s leading edge, and eliminates the low pressure air that normally pulls rearward on the fork crown. |
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