Aero road meets all-rounder: Ridley's WorldTour-proven Noah Fast Disc against the Specialized Tarmac SL8, Rider-First Engineered race bike used by Soudal Quick-Step. Both flagships chase sub-700g frame weights with aero tube shaping - this guide breaks down geometry, fit, and which one wins for your size.
$6,500 - $12,500
Best for: Aero road racing, criteriums, and breakaway efforts
$5,000 - $14,000
Best for: All-around road racing from crits to Grand Tours
| Aspect | Ridley Noah Fast Disc | Specialized Tarmac SL8 |
|---|---|---|
| Reach (M / 54) | 388mm | 386mm |
| Stack (M / 54) | 547mm | 538mm |
| Frame Weight (top build) | 920g | 685g (S-Works) ✓ |
| Tire Clearance | 32mm | 32mm |
| Aero Integration | Full integrated F-Bar ✓ | Aero shaping, optional integrated bar |
| Cockpit Adjustability | Limited (integrated bar) | Flexible (standard option) ✓ |
| Warranty | Lifetime frame (registered) | Lifetime frame |
| Measurement | Ridley Noah Fast Disc | Specialized Tarmac SL8 | ||||||
|---|---|---|---|---|---|---|---|---|
| Size | XS | S | M | L | 49 | 52 | 54 | 56 |
| Stack (mm) | 505 | 525 | 547 | 569 | 502 | 520 | 538 | 558 |
| Reach (mm) | 377 | 382 | 388 | 394 | 370 | 378 | 386 | 391 |
A Ridley M Noah Fast Disc (stack 547 mm, reach 388 mm) is the closest fit to a Specialized 54 Tarmac SL8 (stack 538 mm, reach 386 mm) - reach is within 2 mm and the Noah Fast sits ~9 mm taller in stack. Riders moving from a 54 Tarmac SL8 to an M Noah Fast keep the same effective reach and gain a touch of bar-height comfort.
Choose the Ridley Noah Fast Disc for true aero road performance, an integrated F-Bar cockpit, and a lifetime frame warranty. Choose the Specialized Tarmac SL8 for Rider-First sizing precision, a lighter top-tier frame, and broader service support.
Ridley Noah Fast Disc - taller stack at the equivalent reach
Specialized Tarmac SL8 - lighter frame and Rider-First per-size tuning