The Tarmac is now in its sixth generation, and the full-carbon SL4 was recently revealed to the world at the Tour de France where select riders are riding prototypes to gather data and provide feedback. The original Tarmac was launched in 2004, after three years of development, and from the start has been a bike for climbers and general classification contenders. Levi Leipheimer, Paolo Bettini and Mario Cipollini have all won a Grand Tour on the Tarmac.
The original Tarmac was recognized by its curved top tube and set the groundwork for carbon bikes of the future. To stay ahead of the curve each year feedback was gathered for changes in the bike’s structure and capabilities; and in 2006 when the SL model was introduced, pro-rider Tom Boonen made a number of suggestions regarding the stiffness-to-weight ratio, size, and efficiency, all leading the Tarmac to it’s most recent changes.
When developing the SL4 prototypes, Specialized made changes to the head tube, front and rear dropouts, and fork to develop one of the lightest framesets in the industry. To increase stiffness, and therefore, acceleration and handling, the King Cobra Head Tube as well as the one-piece bottom bracket and chainstays and seatstay are all newly designed for the SL4 version. Finally, internal cable routing is added for internal protection from the elements and carbon dropouts with steel inserts increase efficiency while adding durability for taking wheels on and off.
In the end, Specialized has listened to their riders and created the Tarmac SL4 to be 19% more stiff and 50 grams lighter than the SL3, resulting in a 1995 gram ride that can handle better than ever before. Keep a look out for the SL4 launch on Specialized’s website and to start arriving in shops this August.