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Decisions, decisions… made easy. With a bike that gives you flat-out advantage on the climbs, the sprints and the straightaways, the only decision you’ll need to make is how nice you want to be to the other guys.
A rider-oriented design approach ensures a frame that is both rooted and responsive, with a ride experience most aero frames can’t match. With a layup engineered to maximise aerodynamics while keeping weight low, the design process for the Sum allowed us to strip away all unnecessary weight within the new aero profile tube shapes - all while maintaining maximum power transfer.
| Component | Specification |
|---|---|
| Frame | SUM |
| Fork | SUM specific |
| Headset | FSA Headset NO.55R 1.5” + 3D |
| Integrated Cables | Yes |
| Component | Specification |
|---|---|
| Wheels | Vision Team 30 |
| Tyres | Continental Ultra Sport 700x25 |
| Maximum Tyre Clearance | 30C (32 mm) |
| Component | Specification |
|---|---|
| Bottom Bracket | Shimano Ultegra SM-BB72 |
| Front Derailleur | Shimano 105 R7100 |
| Rear Derailleur | Shimano 105 R7100 |
| Crankset | Shimano 105 FC-R7100 (50/34) |
| Chain | Shimano 105 CS-R7100 |
| Cassette | Shimano 105 CS-R7100 (11-34) |
| Component | Specification |
|---|---|
| Brakes | Shimano 105 R7120 |
| Brake Levers | Shimano 105 R7120 |
| Rotors | Avid DB16SEP21 |
| Rotor Size | Front: 160 mm / Rear: 140 mm |
| Component | Specification |
|---|---|
| Handlebar | Control Tech |
| Stem | FSA SMR-II |
| Bar Tape | Prologo |
| Saddle | Prologo Kappa RS |
| Seatpost | SUM specific |

| Size | XXS (44–46) | XS (47–50) | S (51–53) | M (54–56) | L (57–59) | XL (60–62) |
|---|---|---|---|---|---|---|
| A. Seat Tube Height (cm) | 39.5 | 42.5 | 46.0 | 50.5 | 55.0 | 59.5 |
| B. Seat Tube Angle (°) | 75.0 | 74.5 | 74.0 | 73.5 | 73.0 | 72.5 |
| C. Head Tube Angle (°) | 71.2 | 72.1 | 72.7 | 72.7 | 72.7 | 73.0 |
| D. Top Tube Length (cm) | 50.3 | 52.0 | 53.8 | 55.7 | 57.8 | 60.0 |
| E. Chainstay Length (cm) | 41.0 | 41.0 | 41.0 | 41.0 | 41.0 | 41.0 |
| F. Wheelbase (cm) | 96.7 | 97.2 | 97.5 | 99.0 | 100.6 | 102.0 |
| G. BB Drop (cm) | 6.9 | 7.3 | 7.7 | 7.7 | 7.7 | 7.7 |
| H1. Head Tube Length 3D (0 mm) (cm) | 6.9 | 8.5 | 10.1 | 12.6 | 15.2 | 18.0 |
| H2. Head Tube Length 3D (15 mm) (cm) | 8.4 | 10.0 | 11.6 | 14.1 | 16.7 | 19.5 |
| H3. Head Tube Length 3D (25 mm) (cm) | 9.4 | 11.0 | 12.6 | 15.1 | 17.7 | 20.5 |
| I. Standover Height (cm) | 67.6 | 70.0 | 72.7 | 76.6 | 80.4 | 84.1 |
| Size | XXS (44–46) | XS (47–50) | S (51–53) | M (54–56) | L (57–59) | XL (60–62) |
|---|---|---|---|---|---|---|
| J. Stack 3D (0 mm) | 47.1 | 49.3 | 51.6 | 54.0 | 56.5 | 59.2 |
| J. Stack 3D (15 mm) | 48.5 | 50.7 | 53.0 | 55.4 | 57.9 | 60.6 |
| J. Stack 3D (25 mm) | 49.5 | 51.7 | 54.0 | 56.4 | 58.9 | 61.6 |
| K. Reach 3D (0 mm) | 37.5 | 38.2 | 38.9 | 39.7 | 40.5 | 41.4 |
| K. Reach 3D (15 mm) | 37.0 | 37.7 | 38.5 | 39.3 | 40.1 | 41.0 |
| K. Reach 3D (25 mm) | 36.7 | 37.4 | 38.2 | 39.0 | 39.8 | 40.7 |
| Saddle Height – Min | 56.5 | 59.5 | 63.0 | 67.5 | 72.0 | 76.5 |
| Saddle Height – Max | 71.5 | 74.5 | 78.0 | 82.5 | 87.0 | 91.5 |
Hello! Need help? Don’t worry, I’ve got you. Tell me what’s up, and I’ll be happy to assist 💁
