Pro bike: Lars Boom's Rabobank Giant TCX Advanced SL

Former cyclo-cross world champ sticks with his tried-and-true

The modified Giant TCR Advanced SL machines that Rabobank typically use at Paris-Roubaix can already accommodate big 27mm-wide tubular tires for extra cushioning on the pavé. But for former cyclo-cross world champion Lars Boom, bigger is better.

This year Boom instead decided to use his familiar Giant TCX Advanced SL carbon 'cross bike, which had more than enough room for the even more voluminous 30mm-wide tubulars he wanted to use to help him float across the cobbles.

Team officials wouldn't comment on the exact make and model of tire Boom was using – they clearly weren't sponsor-correct Vittorias – but the tread design and overall appearance suggested to us that they came from Dugast. Team mechanics did say, though, that Boom ran inflation pressures of just 72psi.

Armed with the bigger tires' extra cushioning, Boom also passed over the traditional box-section aluminum tubular wheels of his teammates in favor of Shimano's now discontinued 24mm-deep Dura-Ace carbon tubulars. As a result, his bike ended up being a full 500g lighter than other Rabobank bikes with an actual weight as pictured here of 7.39kg (16.29lb) – definitely more in keeping with some of the lighter Paris-Roubaix machines we've profiled this year.

Lars Boom's tires weren't marked nor would team officials disclose their maker but they look like Dugast's Paris-Roubaix tread glued onto 30mm-wide casings

Like a few other Shimano-sponsored riders who run Dura-Ace Di2 on their everyday race machines, Boom switched to the mechanical version for Paris-Roubaix despite the system's increased susceptibility to housing contamination and longer shift lever throws. According to team mechanics, Boom felt that Di2's super-short button throws were too sensitive when his fingers were bouncing around on the pavé and didn't want to run the risk of a mis-shift during the race.

Typical Paris-Roubaix tweaks to the otherwise standard Dura-Ace 7900 group include 53/44T gearing (which Shimano now offer in matched sets to retain the stock setup's superb shift performance) and a tight-ratio 11-23T cassette the better suit the flat parcours. Noteworthy is the fact that unlike many other racers that day, Boom went without a chain watcher.

Tight 11-23T spacing on Boom's Giant TCX Advanced SL for Paris-Roubaix

Shimano don't make Dura-Ace cantilever brakes, so Giant and Rabobank instead commissioned lightweight aluminum brakes – anodized in team orange and blue colors – from one of their prototype suppliers in Taiwan. "These are new prototypes [done by] the same guy who makes the time trial brakes for us (Giant and Rabobank), the "standard" cross brakes for the Rabo team, and some other parts and projects with us," said team technical director Andy Wollny. "It's a small Taiwanese company – no big name, but very flexible and always able to help me to make special parts in a short time."

Boom's brakes feature simple dual-aluminum plate construction with no frills like spring covers or fancy hardware to keep the weight low. Ball-joint cartridge holders and slotted arms allow for proper pad placement, though, and tidy set screws are on hand for easy and precise centering. The low-profile configuration produces more power than the wide-profile brakes Boom usually uses for 'cross.

There's easily a finger's width of room on all sides of the front tire on Boom's Giant TCX Advanced SL, even with a bulbous 30mm casing

Boom's bike is finished with PRO's Vibe carbon-wrapped stem and PLT Anatomic aluminum handlebar, Shimano Dura-Ace PD-7810 aluminum-bodied pedals, an FSA headset, a Fi'zi:k Arione CX saddle and a pair of Tacx Tao cages. Boom ultimately finished 12th on the day.

Complete bike specifications

  • Frame: Giant TCX Advanced SL, size L/56.5cm
  • Fork: Giant TCX Advanced SL, 1-1/8 to 1-1/4in tapered
  • Headset: FSA Orbit integrated, 1-1/8 to 1-1/4in tapered
  • Stem: PRO Vibe, 130 x -6°
  • Handlebar: PRO PLT Anatomic, 42cm (c-c)
  • Tape: PRO cork
  • Front brake: Rabobank custom aluminum cantilever by Giant w/ Shimano carbon-specific pads
  • Rear brake: Rabobank custom aluminum cantilever by Giant w/ Shimano carbon-specific pads
  • Brake levers: Shimano Dura-Ace STI Dual Control ST-7900
  • Front derailleur: Shimano Dura-Ace FD-7900-F
  • Rear derailleur: Shimano Dura-Ace RD-7900
  • Shift levers: Shimano Dura-Ace STI Dual Control ST-7900
  • Cassette: Shimano Dura-Ace CS-7900, 11-23T
  • Chain: Shimano Dura-Ace CN-7900
  • Crankset: Shimano Dura-Ace FC-7900, 175mm, 53/44T
  • Bottom bracket: Shimano Dura-Ace SM-7800-P
  • Pedals: Shimano Dura-Ace SPD-SL PD-7810
  • Wheelset: Shimano Dura-Ace WH-7850-C24-TU
  • Front tire: Custom Dugast Paris-Roubaix tubular, 30mm
  • Rear tire: Custom Dugast Paris-Roubaix tubular, 30mm
  • Saddle: Fi'zi:k Arione CX K:ium
  • Seatpost: Integrated
  • Bottle cages: Tacx Tao (x2)

Critical measurements

  • Rider's height: 1.91m (6ft 3in)
  • Rider's weight: 78kg (172lb)
  • Saddle height, from BB (c-t): 817mm
  • Saddle setback: 77mm
  • Seat tube length, c-t: 554mm
  • Seat tube length, c-c: 543mm
  • Tip of saddle nose to C of bars (next to stem): 604mm
  • Saddle-to-bar drop (vertical): 134mm
  • Head tube length: 175mm
  • Top tube length: 575mm
  • Total bicycle weight: 7.39kg (16.29lb)

Related Articles

Comments

Back to top