TREK Speed Concept

Last July we saw the Astana Cycling team sporting very fancy new bikes at the first Time Trial that no one had seen before or even heard rumours of. Since then there have been a few leaks on news websites about it coming to the market and what some of the weird shapes of the bike were all about.

Words like "Kammtail" and "Virtual Aerofoil" are being tossed around wildy but what does it all really mean.

A "Kamm Tail" or "Kammback" is a term from the Automotive Industry which is derived from the research of the German aerodynamicist Wunibald Kamm from the 1930s. The design calls for a body with smooth contours that continues to a tail that is abruptly cut off. This shape reduces the air resistance of the vehicle.

Trek have used this design to stay within the UCI specifications for tube shape which states that any tube must not exceed a 3:1 ratio for its profile. The Kammtail or virtual aerofoil allows the tube shape to perform like an aerofoil shape with an 5:1 ratio even though physically its no where near that size. The other feature that has created a lot of hype is the way that this design performs in cross winds.

The Kammtail Virtual Foil (KVF) tube shape is unique in bicycles. We started with a super-slippery 5:1 airfoil, then cut off the tail at just the right length to trick the wind into thinking the full foil is still there, creating a super-aero virtual tail	Less drag at all crosswind angles and a lighter frame mean greater speed from the power you put to the pedals. The Speed Concept 9 Series conquers the wind—and the competition.	Unlike a conventional airfoil, the KVF tube shape retains full aero benefit at yaw. The virtual tail bends to maintain its aero shape in the presence of the most prevalent crosswinds.

The Kammtails Virtual Foil means that as the air passes over the aerofoil it performs as if the complete aerofoil shape is still present. It becomes interesting when you look at how this design performs in situations where the wind is at an angle rather than coming from directly in front or behind. The air that approaches The virtual tail which is the area that is non existent behind the aerofoil shape as shown in the first image, appears to bend or curve giving the "Kammtail" far superior cross wind performance when compared to traditional aero tube shapes.

If you want to read more about the new design, read on at Cycling News or Trek Bikes Website

Along with the update to the frame tubing the new Speed concept bikes also feature hidden brakes front and rear to enhance the aero effect, full internall cable routing to ensure that the aerofoils are not disturbed, integrated speed and cadence sensors and quick release skewers which makes for one of the cleanest finished bikes available. Trek have also manufactured storage accessories specifically designed for the Speed Concept bikes that actually add to the aero effect making the bike more efficient with them fitted than without.

The Speed Concept is available in three specifications for the 9 series OCLV2 carbon frame and three specifications in the 7 series TCT carbon frame. You also have the option with the 9 series bikes of choosing your own custom paint scheme and specification to make a completely one off bike.

For full specs check the Trek Bikes website.

Trek are claiming this to be the fastest bike ever, I guess only time will tell although Astana's Time Trial performance last year was pretty good. Is it the bike?

Cheers
Raenier