Extended Kammtail
Achieving a balance between optimised aerodynamics and cycling performance is a complex challenge, with the stiffness and weight requirements of a bike creating additional constraints.
Traditional high aspect ratio aerofoils are significantly less efficient when designing an aerodynamic road bike frameset, as lateral and torsional stiffness requirements, and the ride and handling performance are more critical than in TT or triathlon bike designs.
Firstly, incorporating a progressive Kamm back aerofoil profile in the lower 1/3 of the down tube, with the extended trailing edge becoming truncated and morphing into a squared-off surface, enabled a significantly more efficient transition from the down tube to seat tube.
But we didn't stop there. Through computational fluid dynamic modeling and extensive wind tunnel testing (which is much more fun that sitting in front of a computer) our aerodynamicists developed a revolutionary design that "tricks" the traditional Kammtail behind the lower down tube to extend further.
The specific proportions of the down tube and seat tube profiles force the airflow to remain laminar around the down tube and seat tube, and rear wheel. The static air above the bottom bracket results in little turbulent energy dissipation in this area.
OTP Aerodynamics
As a frame cuts through the wind, the airflow varies dramatically along every tube, joint and transition, e.g. the airflow upstream of the upper 1/3 of down tube is already turbulent due to the front wheel, however in the lower 1/3 of the down tube upstream airflow is near laminar. The complex interaction of frame and forks, with wheels and components, at a variety of wind yaw angles, and most importantly incorporating the rider, necessitates the airflow to be managed specific to the aerodynamic characteristics of each element.
The design of the Alize achieves this through the complex morphing of every tube profile and joint. We couldn't just settle for the cookie-cutter approach of using a standard aerofoil profile along the length of every tube. If only bike aerodynamics were that simple.
But where do you start? With some guys who know a thing or two about the wind… and Computational Fluid Dynamics… or a virtual wind tunnel to you and me.
C6.7 Carbon Fibre
20 years experience utilising carbon fibre in high performance products. NeilPryde C6.7 high-modulus unidirectional carbon fibre developed exclusively for our cutting edge racing bikes.
QFIT/Aero Seat Clamp System
All NeilPryde bikes come fitted with QFIT and integrated seat clamp. In normal use, the QFIT indicator sits right on top of the jacketed seat clamp. Both systems are a proprietary patent protected design by NeilPryde.
All NeilPryde bikes come fitted with QFIT and integrated seat clamp. In normal use, the QFIT indicator sits right on top of the jacketed seat clamp. Both systems are a proprietary patent protected design by NeilPryde.
QFIT:
The QFIT system is a tight-fitting grey rubber seal, which marks the rider's saddle height whenever he needs to remove the seat post from the frame, for example when shipping.Main Benefits:
- The rider always has a point of reference to work with for saddle height, this means no more inaccurate measuring.
- The QFIT also prevents water, grit and dirt from getting inside the seat tube.
Aero Seat Clamp:
The aero cover for the seat clamp is a simple to use design that helps to reduce the drag by creating an aerodynamically clean shape around the seat clamp. Combined with the QFIT, it creates an intelligently designed solution for an area of the bike often overlooked.Please refer to the owner's manual how to set up the QFIT system.