2017 Specialized Diverge Sport A1 vs 2018 Surly Midnight Special
The 64 is the Surly Midnight Special size closest to your 61 Specialized Diverge Sport A1. We match frame stack and reach. This is a geometry comparison, not a fit recommendation; stem, spacers, handlebars and saddle setup also affect your riding position.
What changes on the Surly Midnight Special
Compared with the Specialized Diverge Sport A1 in 61, the Surly Midnight Special in 64 places the top of the head tube 3 mm lower and 25 mm further forward, relative to the bottom bracket. Its wheelbase is 11 mm longer, which can contribute to stability at speed.
- Frame stack
- −3 mm
- Lower front end
- Frame reach
- +25 mm
- Longer frame reach
- Wheelbase
- +11 mm
- Longer: steadier at speed
- Head angle
- +1.0°
- Steeper: sharper steering
- Chainstays
- +5 mm
- Longer: more planted
The two frames
Specialized Diverge Sport A1, 61Surly Midnight Special, 64Drawn to scale and lined up at the bottom bracket.
Geometry side by side
| Measurement | Specialized Diverge Sport A1 61 | Surly Midnight Special 64 | Difference |
|---|---|---|---|
| Reach | 398mm | 423 | +25 mm |
| Stack | 644mm | 641 | −3 mm |
| Head tube angle | 73° | 74.0 | +1.0° |
| Seat tube angle | 72.5° | 72.5 | ±0.0° |
| Effective top tube | 601mm | 625 | +24 mm |
| Chainstay length | 420mm | 425 | +5 mm |
| Wheelbase | 1039mm | 1050 | +11 mm |
| BB drop | 70mm | 65 | −5 mm |
| BB height | 275.5mm | not listed | |
| Standover | 851mm | 895 | +44 mm |
| Seat tube length | 535mm | 640 | +105 mm |
| Fork length | 400mm | 400 | ±0 mm |
| Head tube length | 214mm | 200 | −14 mm |
Differences are the Surly Midnight Special minus the Specialized Diverge Sport A1. Full charts: 2017 Specialized Diverge Sport A1, 2018 Surly Midnight Special.
Where each sits in its class
Specialized Diverge Sport A1Surly Midnight Special
Each bike is ranked against the other gravel bikes on Quiver, on frame geometry alone. Not your hand position or ride feel.
What each ships with
The stock build of each bike's first listed trim. Parts that match are dimmed.
| Part | Specialized Diverge Sport A1Sport A1 | Surly Midnight SpecialMidnight Special |
|---|---|---|
| Shifter | Shimano Sora | SRAM Rival 22 |
| Derailleur | Shimano Sora | SRAM Rival 22 |
| Chain | KMC X9 | KMC X11 |
| Crankset | Praxis Alba | SRAM S390 |
| Wheelset | Specialized Axis Sport | Alex Rims Adventurer 2 |
| Tire | Specialized Espoir Sport | WTB Horizon Road Plus |
| Brake | Tektro Mira | TRP Spyre |
| Saddle | Specialized Toupé Sport | WTB Volt Sport |
| Frame | not listed | Surly Midnight Special |
| Cassette | not listed | SunRace CS-MS8 |
| Chainring | not listed | SRAM Rival 22 |
| Bottom bracket | not listed | SRAM S390 |
| Rotor | not listed | TRP Spyre |
| Handlebar | not listed | Salsa Cowbell 3 |
| Stem | not listed | Promax DA-296 |
| Headset | not listed | Cane Creek 40 |
| Seatpost | not listed | Promax SP-2019 |
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