Cannondale Synapse Carbon geometryRoad · 2025 · 7 sizes, from 44 to 61

The Cannondale Synapse Carbon is a road bike available in 7 sizes, from 44 to 61. Stack ranges from 510 to 640 mm and reach from 366 to 402 mm. Its geometry is tall and short, built for comfort. Data from 2025; geometry from 2021 is also available.

Stack510–640mm

Reach366–402mm

Head angle69.8–71.3°

Chainstay length425–430mm

PlantedStable rearCalm steeringSlack seat angle

What size Synapse Carbon 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 510 · R 366

48S 530 · R 371

51S 550 · R 376

54S 570 · R 381

56S 590 · R 387

58S 610 · R 393

61S 640 · R 402

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

Geometry chart by size

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

Size	44	48	51	54	56	58	61
Stack	510	530	550	570	590	610	640
Reach	366	371	376	381	387	393	402
Effective top tube	522	533	544	555	567	580	598
Actual top tube	478	486	497	509	523	537	556
Head tube length	91	108	127	150	171	196	227
Head angle	69.8°	70.9°	71.3°	71.3°	71.3°	71.3°	71.3°
Chainstay length	425	425	425	425	430	430	430
Wheelbase	1,003	1,005	1,013	1,026	1,044	1,058	1,077
Front centre	589	592	600	612	624	638	657
BB drop	75	75	75	73	73	70	70
BB height	278	278	278	280	280	283	283
Fork length	393	393	393	393	393	393	393
Fork offset	55	55	55	55	55	55	55
Trail	71	64	61	61	61	61	61
Standover	714	722	752	785	815	843	878
Seat tube (method not stated)	407	407	443	480	520	550	590
Seat angle (method not stated)	73.0°	73.0°	73.0°	73.0°	73.0°	73.0°	73.0°

Source: Cannondale 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

Pinarello Dogma X · 5102026−2 mm+0 mmCompare →

Pinarello NEW Dogma X · 5102026−2 mm+0 mmCompare →

BMC Roadmachine · 542027±0 mm+2 mmCompare →

KTM Revelator Syro Prestige · M2027+3 mm−1 mmCompare →

KTM Revelator Syro Prime · M2027+3 mm−1 mmCompare →

KTM Revelator Syro Master · M2027+3 mm−1 mmCompare →

Frequently asked questions

What size Synapse Carbon 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 510/366 mm in size 44 to 640/402 mm in size 61). 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 Synapse Carbon in size 54?

Stack of 570 mm and reach of 381 mm, with an effective top tube of 555 mm and a head angle of 71.3°.

Is the Synapse Carbon a racing or an endurance bike?

Endurance. In size 54 its stack-to-reach ratio is at percentile 73 of road bikes: a tall, short position.