Which is better, the Cervelo R5 or the Specialized Tarmac SL8?

Both are excellent road bikes. The Cervelo R5 and Specialized Tarmac SL8 excel in different areas — sizing, geometry, and riding style all factor in. Use our side-by-side comparison above to see which fits your body measurements and riding goals.

How do Cervelo and Specialized sizing compare?

Cervelo and Specialized use different sizing systems. A medium in one brand may not match a medium in the other. Always check the specific size chart for each model and compare stack, reach, and standover height for the best fit.

Is the Cervelo R5 good for beginners?

The Cervelo R5 can work for beginners depending on the specific build and geometry. Consider factors like stack height (upright vs aggressive), standover clearance, and tire clearance. Our bike size calculator can help determine if it's the right fit for your measurements.

What size Specialized Tarmac SL8 should I get?

The right size depends on your height and inseam measurement. Use our bike size calculator with your measurements, then cross-reference with the Specialized size chart to find your ideal frame size for the Tarmac SL8.

Can I use the same size in both Cervelo and Specialized?

Not necessarily. Even within the same size label (e.g., "Medium"), Cervelo and Specialized frames may have different effective top tube lengths, reach, and stack measurements. Always compare the geometry tables rather than relying on size labels alone.

Road Bike

Cervélo R5 vs Specialized Tarmac

Lightweight race bike showdown between two of the most celebrated road racing platforms. Both are Grand Tour-proven machines built for climbers and all-rounders who demand the lightest, stiffest frames available.

Side-by-Side Overview

Cervelo R5

$5,500 - $13,000

Best for: Pure climbing and all-around road racing

Strengths

•Ultra-light carbon frame under 800g
•Exceptional stiffness-to-weight ratio
•Proven Grand Tour pedigree with Jumbo-Visma
•Clean internal cable routing
•Balanced aero integration without sacrificing weight

Considerations

•Premium pricing across all builds
•Less aero optimization than the S5
•Limited tire clearance at 30mm

Specialized Tarmac SL8

$4,500 - $14,500

Best for: All-around racing from crits to Grand Tours

Strengths

•Rider-First Engineered frame sizing
•Sub-700g frame weight on top tier
•Excellent power transfer and stiffness
•Wide range of build options and price points
•Aero tube shaping with lightweight focus

Considerations

•Slightly harsh ride on rough roads
•S-Works pricing is very high
•Proprietary seatpost limits adjustability

Head-to-Head Comparison

Aspect	Cervelo R5	Specialized Tarmac SL8
Frame Weight (56cm)	790g	685g (S-Works) ✓
Tire Clearance	30mm	32mm ✓
Stack (56cm)	556mm	548mm
Reach (56cm)	389mm	385mm
Stiffness (BB)	Excellent	Excellent+ ✓
Ride Compliance	Good ✓	Moderate
Value (mid-range build)	Good	Good

Sizing Comparison

Cervélo uses traditional 48-61cm sizing with precise stack and reach values. Specialized uses Rider-First Engineered sizing from 44-61cm, meaning each frame size gets unique tube proportions rather than scaled geometry. The Tarmac generally runs slightly more compact in reach per size. Riders between sizes on Cervélo should consider the smaller frame with a longer stem, while Specialized's wider size range typically provides a closer fit. Both bikes have relatively aggressive race geometry with low stack heights.

Verdict

Choose the Cervélo R5 for its proven climbing pedigree and balanced ride quality at the top end. Choose the Specialized Tarmac SL8 for wider build options, Rider-First sizing precision, and slightly better aero performance at race speeds.