Description
Specialized Tarmac SL8 Expert Ultegra Di2 Road Bike 2025
The Tarmac SL8 is the fastest race bike ever created, combining unprecedented aerodynamics, lightweight construction, and exceptional ride quality. After eight generations and more than two decades of innovation, it's not just the fastest Tarmac, it's the world's fastest race bike. Ready to push your limits?
AERO IN EVERYTHING: Aerodynamics are key, and the Tarmac SL8 is optimised for it in every detail. The new nose cone, called the Speed Sniffer, sharpens the leading edge by moving the steer tube back, resulting in the most aerodynamic road bike Specialized has ever made. Utilising new UCI rules, the Tarmac SL8 also features the narrowest, most aero seat post ever designed by Specialized, ensuring smoother airflow around the legs for maximum speed.
MINIMUM WEIGHT, MAXIMUM AERO: By incorporating lessons from the Aethos, the Tarmac SL8 is built to hit the UCI weight minimum with a full aero setup, boasting a frame that weighs just 685 grams, 15% lighter than the SL7. This lighter weight doesn't compromise aerodynamics, making the SL8 lighter than any bike on the World Tour. The frame design efficiently carries loads, eliminating the need for additional carbon stiffness layers.
GOES LIKE HELL, RIDES LIKE HEAVEN: With a 33% improvement in stiffness-to-weight over the SL7, the Tarmac SL8 offers next-level handling, responsiveness, and comfort. It’s stiffer at the pedals, more precise at the bars, and provides a compliant ride in the saddle, setting a new benchmark for race bike comfort. The SL8 delivers 6% more compliance, gliding over rough roads with a unique suppleness. The proven geometry and 32mm tyre clearance ensure versatility and ease of adaptation.
BEYOND GENDER: Specialized believes that gender doesn't dictate the best bike for a rider. The Tarmac SL8 is designed for all cyclists, offering the same unparalleled ride quality and performance to everyone.
The Tarmac SL8 Expert Di2 features a full Ultegra Di2 groupset, C38 carbon tubeless-ready wheelset, and an SL7 stem with Specialized Expert Shallow Drop alloy handlebars, making it an accessible, performance-packed option for serious cyclists.
Technical Specification
| Frame/Fork | FACT 10r Carbon, 12x100mm thru-axle, flat-mount disc |
| Handlebars | Specialized Expert Shallow Drop, alloy, 125mm drop x 75mm reach |
| Stem | Tarmac integrated stem, 6-degree |
| Tape | Supacaz Super Sticky Kush |
| Saddle | Body Geometry Power Expert |
| Seatpost | S-Works Tarmac SL8 Carbon seat post, FACT Carbon, 15mm offset |
| Seat Binder | Tarmac integrated wedge |
| Front Brake | Shimano Ultegra Di2 R8170, hydraulic disc |
| Rear Brake | Shimano Ultegra Di2 R8170, hydraulic disc |
| Chain | Shimano Ultegra, 12-speed |
| Crankset | Shimano Ultegra R8100 |
| Chainrings | 52/36T |
| Bottom Bracket | Shimano Threaded BSA BB |
| Front Derailleur | Shimano Ultegra R8150, braze-on |
| Rear Derailleur | Shimano Ultegra Di2 R8150, 12-speed |
| Shift Levers | Shimano Ultegra R8170, hydraulic disc |
| Cassette | Shimano Ultegra, 12-speed, 11-30t |
| Front Wheel | Roval C38, 21mm internal width carbon rim |
| Rear Wheel | Roval C38, 21mm internal width carbon rim |
| Front Tyre | S-Works Turbo, folding bead, 700x26mm |
| Rear Tyre | S-Works Turbo, folding bead, 700x26mm |
| Inner Tubes | Turbo Ultralight, 48mm Presta valve |
Built, Checked, Tuned and Tested
All our bikes are fully built, checked, tuned and tested by our Cytech qualified mechanics and then securely packaged, ready for delivery. All you have to do is add the pedals (if included), attach the handlebars to the stem and tighten them following the included detailed instructions or by watching our video and using the provided FREE tools. Visit our Bike Assembly page to see how you assemble your new bike once you receive it.
All bikes collected from our shop, are built, tested and ready to ride. For hassle-free home delivery and bike set-up from a qualified mechanic use our Premier Delivery Service.
Please note, occasionally, manufacturers may change the specification without notice. Bicycles do not come with pedals unless otherwise specified. Bikes ordered for delivery will not arrive with the pedals installed, please refer to the owners manual and pedal installation guides provided for guidance. We do not install accessories to bikes, including mudguards. Bikes ordered for delivery that have tubeless compatible tyres and rims will arrive with inner tubes installed or with tubeless valves installed, this will be brand dependent. Sealant is available to be purchased separately.
If you require any assistance please contact our Customer Care team.
Size Guide
Specialized Tarmac SL8 Expert Ultegra Di2 Road Bike 2025 Sizing
Delivery & Returns
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Why buy your bike from Sigma Sports?
Don't hesitate to reach out to us. It's our goal to answer all of your questions and offer the best advice from our experts. We’ll be happy to answer any questions you may have. Contact us now or visit us in-store.
Save up to 42% with any one of our 11 Cycle to Work partners, and get the health benefits of a new bike in exchange for tax free salary sacrifice. To find out more about our various partners and how to apply click here.
Choose between Free Bike Delivery - to your home or place of work - or our new Premier Bike Delivery Service £99.99 and have your bike delivered "ready to ride" and set up to your measurements with seatpost and pedals adjusted on arrival by a qualified bike mechanic. Either way, our Customer Care team will be in touch to arrange a delivery date to suit you.
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