Pro bike: Lars Boom’s Specialized S-Works Tarmac

2015 Astana team bike of former CX World Champion

Lars Boom is a former cyclocross and time trial world champion (under 23), and consistently proves himself to be a rider to watch. With the classics season approaching, Boom will no doubt be eager to take to the cobbles with the speed and skill that won him the fifth stage of the 2014 Tour de France.


For 2015, and the first time in his professional cycling career, Boom leaves the Dutch Radobank-come-Belkin squad to join the Astana Pro Team, alongside the likes of last year’s Tour de France winner Vicenzo Nibali.

Lars boom at the 2015 tour down under on his debut with astana :

Boom joins Astana for 2015

With a new team comes a new bike and with three WorldTour teams on Specialized for 2015, Boom’s S-Works Tarmac is undoubtedly the most common bike in the peloton.

Where the Specialized bikes of Etixx-Quickstep and Tinkoff-Saxo are quite similar, the Astana team bikes differentiate themselves with colourful paint, Campagnolo groupsets and Corima wheels. Astana is the only WorldTour team to use Corrima wheels.

As seen at the Tour Down Under in January, Boom’s Specialized S-Works Tarmac features a Campagnolo Super Record 11-speed groupset. While electronic groupsets are the most common choice in the WorldTour, the Dutch rider sticks with the mechanical version of the Italian brand’s luxurious group.

As a sponsored team, astana use the srm power meter spider with specialized s-works cranks. 135 bcd campagnolo chainrings finish the assembly :

SRM power meter meets Specialized S-Works cranks

The groupset is not entirely Campagnolo, however – the eagle-eyed among you will have spotted the equally desirable SRM Specialized S-Works crank – a carbon-arm BB30-compatabile crankset that uses a Hirth coupling joint similar to that of Campagnolo’s Ultra Torque.

The 53/39T Campagnolo chainrings meet a relatively enormous 12-29T cassette.

Astana is the only team in the worldtour to be rolling on corima wheels:

These Corima wheels are claimed to weigh 1230g for the pair

Wrapped in Specialized tubulars, the French-made Corima S+ wheels feature 47mm deep carbon rims and use thin and super light Sapim CX-Ray bladed spokes. Sponsored by CeramicSpeed, sealed ceramic bearings feature in the hubs and bottom bracket.  

Towering at 1.91m (6ft 3in) and weighing just 72 kg (158.4lb), Boom is certainly of a lanky build. Despite this and his time trial prowess, his cyclocross background still shows in his setup – spot the 44cm handlebar from FSA.

First seen on lars boom’s bike, the stub-nose specialized power saddle:

This prototype saddle from Specialized looks to be a new competitor to the nose-less ISM saddles

We reported on the near nose-less Specialized Power saddle earlier this week. The saddle is an usual shape compared to the traditionally shaped saddles on nearly every other rider’s bike. This shortened saddle means Boom’s setback measurement is an unusually massive 136mm, despite his actual position being rather standard.

Complete bike specifications

  • Frame: Specialized S-Works Tarmac – size 56cm
  • Fork: Specialized S-Works Tarmac carbon
  • Headset: Tapered sealed
  • Stem: FSA OS-98, 130mm x -6 degrees
  • Handlebar: FSA Omega Compact, 44cm (c-c)
  • Tape: Specialized S-Wrap Roubaix
  • Front brake: Campagnolo Super Record
  • Rear brake: Campagnolo Super Record
  • Brake levers: Campagnolo Super Record
  • Front derailleur: Campagnolo Super Record
  • Rear derailleur: Campagnolo Super Record
  • Shift levers: Campagnolo Super Record
  • Cassette: Campagnolo Super Record, 12-29T
  • Chain: Campagnolo Record
  • Crankset: SRM Specialized S-Works, 175mm, Campagnolo 53/39T chainrings
  • Bottom bracket: CeramicSpeed
  • Pedals: Look Keo Blade 2 CroMo
  • Wheelset: Corima 47mm S+ tubular
  • Front tyre: Specialized Turbo tubular, 24mm
  • Rear tyre: Specialized Turbo tubular, 24mm
  • Saddle: Specialized S-Works Power – prototype model
  • Seatpost: FSA K-Force SB25
  • Bottle cages: Tacx Tao (2)
  • Computer: SRM Power Control 7 (not pictured)
  • Accessories: Campagnolo chain catcher, ANT+ speed sensor on front wheel

Critical measurements

  • Rider’s height: 1.91m (6ft 3in)
  • Rider’s weight: 72 kg (158.4lb)
  • Saddle height from BB, c-t: 810mm
  • Saddle setback: 136mm
  • Seat tube length (c-t):  501mm
  • Tip of saddle to center of bar: 660mm
  • Saddle-to-bar drop: 130mm
  • Head tube length: 160mm
  • Top tube length (effective): 565mm
  • Total bicycle weight: 7.16kg (15.75lb) without SRM computer)