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  • Synapse carbon frame features optimized tube shaping to promote efficiency and comfort; frame geometry gives a more upright position than more race-oriented road frames
  • Rear part of the frame and the all-carbon fork feature the Cannondale Synapse Active Vibration Elimination (S.A.V.E.) technology for damping road vibration
  • FSA Cannondale Si compact crankset is paired with an 11-32T cassette for a capable gear range; BB30 bottom bracket enhances stiffness for efficient power transfer
  • Shimano 105 derailleurs supply precise, dependable shifts throughout the 22 gear combinations
  • Mavic Aksium wheelset is decked out with fast Schwalbe Lugano tires for excellent handling and speed
  • Pedals sold separately
  • Specs are subject to change


All bicycles sold at REI include a free warranty tune-up. New bikes go through a normal break-in period, after which readjustment is important for longevity and performance. Bring your new bike in to your local REI for its free tune-up within 20 hours of use or 6 months from purchase, whichever comes first. Contact your nearest REI bike shop to schedule this important service.

Free shipping & Assembly with REI Store Pickup

Cannondale bikes purchased on must be shipped to and picked up at REI stores which are authorized Cannondale dealers. The bikes are fully assembled and the shipping is free!

See the current list of REI stores which are authorized Cannondale dealers.

View all Cannondale Endurance Bikes

REI membership


Best Use Road Cycling
Frame BallisTec carbon
Fork BallisTec carbon
Bike Suspension No Suspension
Crankset Cannondale Si, 50/34
Bottom Bracket FSA BB30
Shifters Shimano 105
Front Derailleur Shimano 105
Rear Derailleur Shimano 105
Rear Cogs Shimano 105, 11-32, 11-speed
Number of Gears 22 gear(s)
Brake Type Rim Brake
Brakes Shimano 105 5800
Brake Levers Shimano 105
Rims Mavic Aksium
Front Hub Mavic Aksium
Rear Hub Mavic Aksium
Wheel Size 700c
Tires Schwalbe Lugano, 700 x 25
Tire Width 25 millimeters
Handlebar Shape Drop Bar
Handlebar Cannondale C3, 6061 alloy
Stem Cannondale C3
Seat Post Cannondale C3 alloy
Saddle Cannondale Stage Ergo
Pedals Sold separately
Headset CAADX Si
Chain Shimano HG600
Weight 18 lbs. 4.8 oz.
Bike Weight Bike weight is based on median size, as sold, or the average of two median sizes.
Gender Unisex

Size chart

Sizing notes

Measurements are stated in centimeters.

Graphic of a bike and its measurements

How we measure bikes

Understanding bike geometry helps you get a perfect fit.

1. Reach

2. Stack

3. Effective Top Tube

4. Seat Tube Center to Top

5. Standover Height

6. Head Tube Length

7. Head Tube Angle

8. Seat Tube Angle

9. Bottom Bracket Height

10. Wheelbase

11. Chainstay Length

12. Fork Offset

Rated 5 out of 5 by from Great ride, hard-to-beat value Sorry, Bob, but I have to counterbalance your review of this bike. First, it's not intended to be a racing bike. Cannondale has other models for that purpose, such as the Supersix Evo and the CAAD12. This is an endurance bike, meant to let riders cover a lot of territory quickly and comfortably. It suits this purpose tremendously well. While you spent a day on this bike, I -- along with 15 other people -- spent 7 straight days riding this model and its women's version equivalent on a tour through Vermont and Quebec. (The bikes were rentals provided by the bike touring company.) We all loved the bike. It absorbed the punishing rural roads well and provided all the climbing and descending power and control we could ask for. The 105 equipment functioned flawlessly. The frame has been heralded by bike review publications as the best in its class, and another rider who normally rides the Felt equivalent of this bike said regretfully that the Cannondale was noticeably better. At this price point, you're unlikely to find a better bike.
Date published: 2016-08-11
Rated 3 out of 5 by from Cannondale Synapse Carbon 105 5 Bike I rode this bike as a loaner while mine was out for repairs. This 56 cm bike has a shorter top tube/stem combo, a higher head tube/headset/handlebar set up than what I normally ride. So to be fair, the bike fit was not my ideal set up. Once rolling I found the the bike has a reasonably stiff rear triangle feel and lively pedal action, does reasonably well with road vibration/chatter, but lacks a powerful feel. Out of the saddle power was poor, due to front end flexibility. I attribute some of that to the taller head tube, but probably more so the tall stem. Overall the bike is a comfortable road cruiser suited to local Sunday club rides. If you are looking for a race bike, this model should be avoided.
Date published: 2016-03-14
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I am 5'8" tall what should be the right size for me?

Asked by: alexc
You're 5'8"... same height as me. The 54cm bikes will fit riders 5'6" - 5'9".
Answered by: Greg
Date published: 2017-06-10
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