Specialized Roubaix SL8 geometryRoad · 2026 · 8 sizes, from 44 to 64

The Specialized Roubaix SL8 is a road bike available in 8 sizes, from 44 to 64. Stack ranges from 543 to 685 mm and reach from 353 to 409 mm. Its geometry is tall and short, built for comfort.

Stack543–685mm

Reach353–409mm

Head angle69.3–73.5°

Chainstay length418–423mm

Low BBRelaxedStable rearPlanted

What size Roubaix SL8 do I need?

Enter the stack and reach of a bike that fits you well and we will tell you which size is closest and how to set it up.

Stack in mm Reach in mm Compare on Fitbikefy →

44S 543 · R 353

49S 549 · R 363

52S 566 · R 370

54S 585 · R 381

56S 605 · R 389

58S 630 · R 397

61S 665 · R 403

64S 685 · R 409

Enter your stack and reach to see which size fits you best.

Geometry chart by size

Measurements in mm and degrees, as published by Specialized. The ones that matter most for choosing a size are in bold.

Size	44	49	52	54	56	58	61	64
Stack	543	549	566	585	605	630	665	685
Reach	353	363	370	381	389	397	403	409
Effective top tube	503	523	534	550	569	584	600	618
Head tube length	90	90	105	122	140	168	202	222
Head angle	69.3°	70.8°	71.5°	72.3°	73.0°	73.0°	73.5°	73.5°
Chainstay length	418	418	418	420	420	423	423	423
Wheelbase	994	992	998	1,005	1,012	1,031	1,042	1,054
Front centre	589	587	593	598	604	620	631	634
BB drop	80	80	80	78	78	78	78	78
BB height	269	269	269	270	270	271	271	271
Fork length	375	375	375	375	375	375	375	375
Fork offset	52	52	52	47	47	47	47	47
Trail	76	66	62	61	57	57	54	54
Standover	686	719	747	766	787	809	847	865
Seat tube (method not stated)	365	410	446	465	485	505	545	581
Seat angle (method not stated)	75.0°	74.0°	74.0°	74.0°	73.5°	73.5°	73.5°	73.0°

Source: Specialized official website · data from 11 Nov 2026.

Stack and reach of every size

Higher means a taller front end; further right means a longer reach. The blue dot is your search.

Character of each size

Compared with other road bikes. Further right means more of that quality.

Positionracing → relaxed

Steeringcalm → quick

Pedallingrearward → forward

Bottom brackethigh → low

Wheelbaselively → planted

Rear endstable → agile

Bikes with similar geometry (size 54)

The closest size of other road models, by stack and reach.

ModelΔ stackΔ reach

Specialized S-Works Roubaix SL8 · 542026±0 mm±0 mmCompare →

Wilier Triestina Granturismo SLR · L2026+1 mm+3 mmCompare →

Wilier Triestina Granturismo SL · L2027+1 mm+3 mmCompare →

Bianchi Infinito · 5502026−1 mm−4 mmCompare →

Pinarello Dogma X · 5252026+3 mm+4 mmCompare →

Pinarello NEW Dogma X · 5252026+3 mm+4 mmCompare →

Roubaix SL8 or S-Works Roubaix SL8? In size 54 they have exactly the same stack and reach (585 / 381 mm): the difference is in the frame and build, not the position.

Frequently asked questions

What size Roubaix SL8 do I need?

It depends on your position, not just your height. The most reliable way is to compare the stack and reach of a bike that fits you with those of each size (from 543/353 mm in size 44 to 685/409 mm in size 64). The size finder on this page shows the closest size and the stem and spacers you would need.

What are the stack and reach of the Roubaix SL8 in size 54?

Stack of 585 mm and reach of 381 mm, with an effective top tube of 550 mm and a head angle of 72.3°.

Is the Roubaix SL8 a racing or an endurance bike?

Endurance. In size 54 its stack-to-reach ratio is at percentile 86 of road bikes: a tall, short position.

Does it have the same geometry as the S-Works Roubaix SL8?

In size 54, yes: same stack and reach. If one already fits you, the same size of the other will put you in the same position.