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1845649 / 54294451880282

Product Details

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.

Features
  • 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
Highlights
  • Ultimate Speed: The Tarmac SL8 is a masterclass in speed, revolutionising aerodynamics and lightweight design to set new standards in ride quality.
  • Minimum Weight, Maximum Aero: Compliant with UCI minimum weight regulations, the Tarmac SL8 weighs just 685 grams, making it 15% lighter than its predecessor.
  • Legendary Performance: With a remarkable 33% improvement in stiffness-to-weight ratio, the Tarmac SL8 delivers unmatched precision and increased pedal stiffness.
  • Inclusivity and Progress: Breaking gender boundaries, this bike is engineered for all cyclists, embodying a commitment to inclusivity and forward-thinking design.
Specifications
Model
Tarmac SL8 Expert
Bottom Bracket [Maker]
Shimano
Bottom Bracket Standard
BSA
Brakes [Kind]
Hydraulic Disc
Brakes [Maker]
Shimano
Brakes [Model]
Ultegra Di2 R8170
Cassette [Gearing]
11-30
Cassette [Maker]
Shimano
Cassette [Model]
Ultegra
Chain [Maker]
Shimano
Chain [Model]
Ultegra
Chainring [Gearing]
52–36
Crank [Maker]
Shimano
Crank [Model]
Ultegra R8100
E-Bike
No
Family
Tarmac
FD [Maker]
Shimano
FD [Model]
Ultegra R8150
Fenders Mounts
No
Fork [Axle Type]
12x100mm
Fork [Brake Type]
Disc
Fork [Maker]
Specialized
Fork [Material]
Carbon
Fork [Model]
FACT 10r Carbon
Fork [Wheel Size]
700c
Frame [Material]
Carbon
Frameset
No
Gearing [Configuration]
2x
Gearing [Kind]
Conventional
Gender
Unisex
Handlebar [Kind]
Drop
Handlebar [Maker]
Specialized
Handlebar [Material]
Aluminium
Handlebar [Shape]
Drop bar
Rack Mounts
No
RD [Maker]
Shimano
RD [Model]
Ultegra Di2 R8150
Saddle [Maker]
Specialized
Seatpost [Kind]
Rigid
Seatpost [Maker]
Specialized
Seatpost [Material]
Carbon
Shifters [Maker]
Shimano
Shifters [Model]
Ultegra R8170
Shifting
Electronic
Stem [Maker]
Specialized
Stem [Material]
Aluminium
Suspension Configuration
Rigid
Tires [Maker]
Specialized
Wheels [Configuration]
Front+Rear
Wheels [Kinds]
700c
Wheelset [Maker]
Roval
Wheelset [Material]
Carbon
Wheelset [Model]
C38
Product code
1845649 / 54294451880282
Size Guide
Specialized Aethos Size Guide 2022

All sizes are shown in millimetres unless otherwise stated.

Reviews
Rating 5 out of 5
5
Value of Product
4.5
Quality of Product
5
Rating 5 out of 5
Daniele,
Verified purchaser

Specialized SL8 Tarmac bike has been set up to perfection. Thanks to Milo at Sigma Sports for the absolutely spot on advice and professionalism. I am enjoying the bike after a few training sessions and a couple of charity events I participated.

Rating 5 out of 5
will123,
Verified purchaser

I bought this to replace a previous bike and so glad I did. It is so responsive and stiff, as well as being still fast on the flat. Really pleased, and looks lovely and clean in the white swell.

Shipping & Returns

Free UK delivery on orders over £50. Orders are dispatched within 1-2 working days and typically arrive 1-2 working days later.

Return unused items in their original packaging within 30 days of delivery. Return postage is £3.50.

Q & A

1 question answered

  1. Hi very interested in the Tarmac SL8 Expert size 54, can the Chainrings be changed to a 50/34 rather than the stock 52/36 and can the rear cassette be changed from the 11-30 stock to an 11-34? I look forward to your response

    Asked by Will (Belfast)

    1. Hi there, Please contact the sales team for help with this, Many thanks Joe W

      Joe W

About Specialized

Innovate or die.

Founded in California in 1974, Specialized began with a simple promise: serious riders deserve serious gear. Half a century later, the brand still funds its own wind tunnel, builds its own carbon, and tests every bike with the world's best so that you ride your own best.

The first production mountain bike. The first cycling-specific shoes. FACT carbon, the Win Tunnel, S-Works. Specialized has a habit of building the things the rest of cycling ends up copying.