2023 Cannondale Synapse Size Charts and Guide

In this article, our road bike specialist Bernard Lu guides you on how to find your ideal Cannondale Synapse size.

Experienced cyclist turned writer with 7+ years working in bike shops, overseeing retail and workshop operations.

This guide provides insights to help you determine the right Cannondale Synapse size.

The Cannondale Synapse is an endurance road bike with a more relaxed geometry compared to the Cannondale Supersix EVO and System Six

There are seven frame sizes tailored for riders between 5’3″ to 6’6″ (160 to 198cm).

Cannondale Synapse sizeRider height (in)Rider height (cm)
445’0″ to 5’4”152 to 162
485’2″ to 5’6″157 to 167
515’5″ to 5’9″165 to 175
545’7″ to 5’11”170 to 180
565’9″ to 6’1″175 to 185
586’0″ to 6’4″182 to 193
616’3″ to 6’8″190 to 203
Cannondale Synapse bike size chart vs. height. Source: Cannondale

Factors to consider beyond your height

From my experience owning multiple bikes, while height is a starting point, achieving the perfect bike fit involves more nuanced considerations.

  • Brand-specific sizing. Bike sizes can differ between brands. A size 51 Cannondale Synapse may not align with a size 51 Cervelo Caledonia. Always consult specific brand measurements over generic size labels.
  • Stack and Reach are two critical measurements to consider. You can find these measurements in the frame geometry chart below.
    • Reach is measured as the horizontal distance from the bottom bracket to the center of the head tube, influencing your riding posture. A longer reach provides an aggressive stance, while a shorter one ensures a relaxed position.
    • Stack is the vertical distance from the bottom bracket to the top of the head tube. It determines the handlebars’ height relative height to the saddle. A higher stack ensures a more upright position, ideal for long rides or riders with back flexibility concerns.
  • Falling in-between sizes. If you’re between two sizes, it’s generally advisable to opt for the smaller size from my experience and observation. A smaller size would allow for more room to make corrective measures if needed.
  • Go for a test ride. Nothing beats a hands-on experience. Visit a local Cannondale dealer, try different sizes, and choose the one that feels just right. Most dealers offer test rides, especially for demo sizes.

Cannondale System Synapse frame geometry (2022-2023)

Diagram of a road bicycle illustrating bike geometry. Two main measurements are highlighted: 'Reach', represented by a horizontal dashed line from the center of the bottom bracket to the top center of the handlebar, and 'Stack', shown as a vertical dashed line from the center of the bottom bracket to the same handlebar point.
Cannondale Synapse frame and reach

The geometry chart below applies to all Cannondale Synapse Carbon frames from the following:

  • Years: 2022, 2023
  • Models: Ltd, 1, 2, 3, 4
  • Frame material: Carbon

The frame geometry measurements are explained in this article.

Frame Size485154565861
Rider Height (cm)157 to 167165 to 175170 to 180175 to 185182 to 194190 to 203
Rider Height (ft)5’2″ to 5’6″5’5″ to 5’9″5’7″ to 5’11”5’9″ to 6’1”6’0″ to 6’4”6’3″ to 6’8”
Stack (mm)530550570590620640
Reach (mm)371376381387393402
Top Tube, Actual (mm)510521533547560579
Top Tube, Horizontal (mm)533544555567579598
Seat Tube (mm)407443480520550590
Seat Tube Angle73.0°73.0°73.0°73.0°73.0°73.0°
Head Tube (mm)109130143164187218
Head Tube Angle71.3°71.4°73.1°73.2°73.3°73.4°
Standover Height (mm)712742773787833868
Wheelbase (mm)991100298799810111028
Front Center (mm)588598583594606623
Chainstay (mm)415415415415415415
BB Drop (mm)757573747070
BB Height (mm)270270272272275275
Fork Offset (mm)555545454545
Fork Trail (mm)595858575656
Cannondale Synapse Carbon (2022-2023) frame geometry chart. Source: Cannondale
Bernard Lu at Mr.Mamil

Bernard Lu has 7+ years of experience working in a bicycle shop, overseeing the retail and workshop operations. He’s a qualified bicycle mechanic who understands a cyclist’s needs and speaks the same cycling lingo.

If you meet him at the cafe, he will happily talk to you for hours about all the intricacies of bikes and cycling tech. Just buy him a coffee next time you see him.