The S-Works Tarmac SL4 is a pure & unbridled race machine. It climbs effortlessly descends confidently & sprints ferociously. Its the lightest stiffest frame we make & it shows as soon as you push on the pedals. Bottom line youll be faster on this bike. Theres a reason its the weapon of choice for the Saxo-Tinkoff Astana & Omega Pharma-Quick-Step Pro Tour teams.> S-Works SL4 FACT 11r carbon frame has our highest stiffness-to-weight ratio ever with tapered headtube OSBB & internal cable routing for race day performance> Full monocoque FACT carbon fork with a tapered carbon steerer is super light with great torsional rigidity for high-speed handling> Pro-quality long-lasting & lightweight Ceramic Speed bottom bracket with ceramic bearings for reduced friction> S-Works FACT carbon seatpost & cradle is super light & stiff for optimal power transfer fully adjustable & accommodates carbon rails Technical Specifications FRAME S-Works SL4 FACT 11r carbon FACT construction tapered/shaped headtube compact race design 1-3/8&34; lower headset bearing carbon OSBBFORK S-Works Tarmac FACT carbon full monocoque OS race for 1-3/8&34; bearing hollow carbon dropouts HEADSET 1-1/8&34; upper & 1-3/8&34; lower hybrid cartridge lightweight bearings 8mm carbon cone spacer w/ 20mm of carbon spacers BOTTOM BRACKET OS integrated Ceramic Speed sealed ceramic bearings SEATPOST S-Works SL FACT carbon 2-bolt 27.2mm SEAT BINDER Forged alloy 32.6mm Ti bolt