2025 Specialized Tarmac SL8 Pro Shimano vs 2025 Trek Émonda ALR
The 47 is the Trek Émonda ALR size closest to your 44 Specialized Tarmac SL8 Pro Shimano. We match frame stack and reach. This is a geometry comparison, not a fit recommendation; stem, spacers, handlebars and saddle setup also affect your riding position.
What changes on the Trek Émonda ALR
Compared with the Specialized Tarmac SL8 Pro Shimano in 44, the Trek Émonda ALR in 47 places the top of the head tube 6 mm higher and 7 mm further forward, relative to the bottom bracket.
- Frame stack
- +6 mm
- Higher front end
- Frame reach
- +7 mm
- Longer frame reach
- Wheelbase
- +2 mm
- About the same
- Head angle
- +1.6°
- Steeper: sharper steering
- Chainstays
- ±0 mm
- About the same
The two frames
Only the Specialized Tarmac SL8 Pro Shimano is drawn. The Trek Émonda ALR numbers we have for size 47 are missing the seat angle.
Geometry side by side
| Measurement | Specialized Tarmac SL8 Pro Shimano 44 | Trek Émonda ALR 47 | Difference |
|---|---|---|---|
| Reach | 366mm | 373 | +7 mm |
| Stack | 501mm | 507 | +6 mm |
| Head tube angle | 70.5° | 72.1° | +1.6° |
| Seat tube angle | 75.5° | not listed | |
| Chainstay length | 410mm | 410 | ±0 mm |
| Wheelbase | 970mm | 972 | +2 mm |
| BB drop | 74mm | 72 | −2 mm |
| BB height | 266mm | not listed | |
| Standover | 723mm | 692 | −31 mm |
| Seat tube length | 433mm | 424 | −9 mm |
| Fork length | 370mm | not listed | |
| Head tube length | 99mm | 100 | +1 mm |
| Effective top tube | not listed | 512 |
Differences are the Trek Émonda ALR minus the Specialized Tarmac SL8 Pro Shimano. Full charts: 2025 Specialized Tarmac SL8 Pro Shimano, 2025 Trek Émonda ALR.
Where each sits in its class
Specialized Tarmac SL8 Pro ShimanoTrek Émonda ALR
Each bike is ranked against the other road bikes on Quiver, on frame geometry alone. Not your hand position or ride feel.
What each ships with
The stock build of each bike's first listed trim. Parts that match are dimmed.
| Part | Specialized Tarmac SL8 Pro ShimanoPro - Shimano Ultegra Di2 | Trek Émonda ALRALR 5 |
|---|---|---|
| Frame | Specialized Tarmac SL8 FACT | not listed |
| Shifter | Shimano Ultegra R8170 Di2 | not listed |
| Derailleur | Shimano Ultegra R8150 Di2 | not listed |
| Cassette | Shimano Ultegra | not listed |
| Chain | Shimano Ultegra | not listed |
| Crankset | Shimano Ultegra R8100 | not listed |
| Wheelset | Roval Rapide CL II | Bontrager Paradigm SL |
| Tire | Specialized S-Works Turbo | Bontrager R1 Hard-Case Lite |
| Brake | Shimano Ultegra R8170 Di2 | not listed |
| Handlebar | Roval Rapide Cockpit | not listed |
| Seatpost | Specialized S-Works Tarmac SL8 | not listed |
| Saddle | Specialized Power | not listed |
| Fork | not listed | Trek Émonda ALR |
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