Pro bike: Ian Boswell's Unbound Gravel 200 winning Specialized Diverge

Unbound gravel has had a rocky few years but, much to the relief to the gravel community, returned last weekend and featured a packed field for 2021. A new name and one significant new face made the headlines as Ian Boswell took the Unbound Gravel 200 victory on his first outing at the legendary gravel event.

The race covers 206.8 miles of mixed surfaces from well-graded gravel to more technical sections that really test bike handling skills. A breakaway featuring some of the biggest names in gravel, and past winners, pushed ahead but when the first riders came into sight of the finish it was just Boswell and Laurens ten Dam left. In a sprint finish, Boswell still had the power to put a turn on ten Dam to take the top spot.

Boswell retired from WorldTour racing at the start of 2020 to focus on gravel racing but due to world events wreaking havoc on race calendars, Unbound Gravel 2021 would only be Boswell's second gravel race and would be the American's longest ride. To tackle such a grueling course, Boswell rode his Specialized Diverge gravel bike with a pretty special 1989 Rock Combo custom-painted design.

Beyond the delightfully retro aesthetic of the frame, the Diverge is an extremely capable bike featuring Specialized's Future Shock 2 suspension system at the front. 

The cockpit area has some more interesting component choices, namely the 130mm stem, which is long, compared to most gravel bike setups, and the unusually shaped Coefficient RR carbon handlebar. The bars have a dramatic shape which Coefficient calls aero-ergonomic and gives the bars a deeper drop with 12 degrees of sweep, 15 degrees of slope and 7 degrees of flare. The integrated computer bridge mounts Boswell's Wahoo Roam and provides additional hand positions to give a more aero position when battling Kansas winds. Interestingly Boswell has added some textured material to the tops of the bars rather than fully wrapping them in the Supacaz bar tape.

The bike features a mullet gravel setup using SRAM's Force 1 crankset (46T chainring), with a Quarq power meter, and Force 1 levers and brakes which is paired with an XX1 derailleur and 10-50T Eagle cassette to offer a huge gear range. Boswell used the titanium-axle version of Look's X-Track Race Carbon cross-country pedals.

Much of the rest of the componentry comes from Specialized, on top of a Terra seatpost there is a Specialized S-Works Power saddle. Tires are Specialized Pathfinder Pros in 42mm, mounted to Roval Terra wheels and protected by Cush Core gravel tire inserts to keep flint-induced punctures at bay.

Any tools, food and other essentials were spread between an Apidura top tube bag, a seatpack and a small backpack. Boswell also had front and rear day running lights for added visibility, a spare ski strap attached to his saddle, course notes stuck to his stem and curiously opted for pipe cleaners - rather than the traditional zip tie - to hold his race number on.

Ian Boswell's custom Specialized Diverge

  • Frameset: Specialized Diverge Size 58cm
  • Handlebars: Coefficient RR
  • Stem: Specialized Future Stem Pro, 130mm
  • Seatpost: Specialized Terra
  • Brake/shift levers: SRAM Force AXS
  • Rear derailleur: SRAM XX1
  • Chain: SRAM XX1
  • Crankset: SRAM Force 1 w/ Quarq power meter, 46T
  • Bottom bracket: SRAM
  • Cassette: SRAM XX1 10-50T
  • Brakes: SRAM
  • Pedals: Look X-Track Race Carbon Ti
  • Wheelset: Roval Terra
  • Tires: Specialized Pathfinder Pro 42mm w/ Cushcore inserts
  • Saddle: Specialized S-Works Power saddle
  • Bar tape: Supacaz
  • GPS Computer: Wahoo ELEMNT BOLT
  • Bottle cages: Specialized Rib Cage II
  • Bottles: Wahoo
  • Accessories: Apidura top tube bag
Graham Cottingham
Senior reviews writer, Bike Perfect

Graham is all about riding bikes off-road, based in Edinburgh he has some of the best mountain biking and gravel riding in the UK on his doorstep. With almost 20 years of riding experience, he has dabbled in downhill, enduro, and gravel racing. Not afraid of a challenge, Graham has embraced bikepacking over the last few years and likes nothing more than strapping some bags to his bike and covering big miles to explore Scotland's wildernesses. When he isn’t shredding the gnar in the Tweed Valley, sleeping in bushes, or tinkering with bikes, he is writing tech reviews for Bike Perfect.


Rides: Cotic SolarisMax, Stooge MK4, 24 Bicycles Le Toy 3, Surly Steamroller

Height: 177cm

Weight: 71kg