S-Works Tarmac SL8 - Shimano Dura-Ace Di2S Works Tarmac SL8 Road Bike Nothing is faster than the Tarmac SL8. Combining cutting edge aerodynamics, ultra lightweight construction, and unmatched ride quality, this is more than just the fastest Tarmac everits one of the fastest race bikes ever created. At Mackay Cycles, we recommend the S Works Tarmac SL8 for serious riders chasing uncompromising performance, whether its racing, climbing, or all out speed on the road. Aero Meets Real World Speed