Pro bike: Brent Bookwalter’s BMC TimeMachine TM01

Wider tyres invade the final front

American rider Brent Bookwalter (BMC) will serve as a key lieutenant to team captain Cadel Evans as he seeks another overall win at the Giro d’Italia. That three-week campaign starts with a team time trial around downtown Belfast in Northern Ireland, where every rider will use BMC’s sleek TimeMachine TM01.


We’ve inspected the TM01 several times since its introduction in 2011 and, three years later, it’s still a visually striking and utterly contemporary-looking machine with aggressive and angular lines, cleverly hidden front and rear brakes, sleek (and extremely narrow) external fork steerer, and highly integrated cockpit setup.

Brakes are neatly hidden away on the bmc timemachine tm01:
James Huang/Future Publishing

The brakes are neatly hidden away on the BMC TimeMachine TM01

Despite its overuse, the term ‘looks fast standing still’ certainly applies here.

The trend we’ve seen with pro riders resorting to smaller-than-typical frame sizes carries over to the time trial side too, at least in this case. Despite standing 1.80m (5ft 11in) tall, Bookwalter has opted for BMC’s smallest available TM01 chassis.

This keeps the base bar height very low and shortens the front centre but also requires a generous stack of spacers beneath the armrests. 36mm of extra stem extension helps push the grips further out too.

Brent bookwalter (bmc) stands 1.8m (5ft 11in) tall but rides a small bmc timemachine tm01. as a result, there’s a healthy stack of spacers to bring his armrests up:

There’s a healthy stack of spacers to bring Brent’s armrests up

More interesting, however, are Bookwalter’s 25mm-wide Continental tubular tyres – a size that until very recently would never have been considered for time trials where rolling resistance and aerodynamics are of paramount importance.

Rolling weight isn’t nearly as critical for most time trials though, and as the pros are increasingly realising, the wider tyres are actually yielding lower times along with other ancillary benefits, such as increased cornering grip, which could prove critical depending on road conditions for the opening team time trial.

25mm-wide continental competition proltd alx tubular tires are fitted front and rear – a size once unheard of for a time trial bike:

25mm wide Continental Competition ProLtd ALX tubular tyres are fitted front and rear – a size once unheard of for a time trial bike

“The riders thought it would be much slower but it’s the exact opposite,” team mechanic Jürgen Landrie told BikeRadar. “It’s faster, more comfortable, and we get fewer flats.”

Landrie did stress, however, that the aerodynamic benefits are only realised when those wider tyres are paired with correspondingly wider rims. In this case, both the PRO Textreme Carbon rear disc and Shimano Dura-Ace WH-9000-C75-TU deep-section front wheel boast compatible 24mm-wide cross-sections.

Claimed weight on pro’s textreme carbon disc wheel is 975g. the wider profile works well with 25mm-wide tires but it’s clearly a tight fit with the rear derailleur:

Claimed weight on PRO’s Textreme carbon disc wheel is 975g. The wider profile works well with 25mm-wide tyres but it’s clearly a tight fit with the rear derailleur

All of this component integration may look impressive when all is said and done but – as is often typical for most top-end TT rigs – it takes quite a bit of work to get to that point. According to Landrie, each of the team’s TM01s can take even a seasoned team mechanic a full day to build and tune to race readiness.

When you consider that there are 28 riders on the WorldTour squad plus the fact that many of the riders have more than one time trial machine at their disposal, those days add up quickly.

The bmc timemachine tm01’s sleek form features hidden brakes front and rear plus a stealth fighter-like aesthetic:

The BMC TimeMachine TM01’s sleek form features hidden brakes front and rear plus a stealth fighter-like aesthetic

If all goes well for Bookwalter and the rest of his BMC team though, all of that time will be very well spent and will feel like a distant memory once the champagne starts to flow.

American rider brent bookwalter (bmc) is using this bmc timemachine tm01 for this year’s giro d’italia time trials:

Complete bike specifications

  • Frame: BMC TimeMachine TM01, size small
  • Fork: BMC Aero Hinge
  • Headset: BMC integrated
  • Stem: BMC integrated w/ 36mm spacers
  • Handlebar: 3T Brezza II Team, 40cm (c-c)
  • Tape: fi’zi:k
  • Front brake: BMC integrated with Shimano carbon-specific pads
  • Rear brake: BMC integrated with Shimano carbon-specific pads
  • Brake levers: Shimano Dura-Ace Di2 ST-9071
  • Front derailleur: Shimano Dura-Ace Di2 FD-9070
  • Rear derailleur: Shimano Dura-Ace Di2 RD-9070
  • Shift levers: Shimano Dura-Ace Di2 ST-9071 and SW-R671
  • Cassette: Shimano Dura-Ace CS-9000, 11-25T
  • Chain: Shimano Dura-Ace CN-9000
  • Crankset: SRM PowerMeter Shimano DA7900, 175mm, 54/42T
  • Bottom bracket: FSA BB-ALM3
  • Pedals: Shimano Dura-Ace SPD-SL PD-9000
  • Front wheel: Shimano Dura-Ace WH-9000-C75-TU
  • Rear wheel: PRO Textreme Carbon Disc tubular
  • Front tyre: Continental Competition ProLtd ALX tubular, 25mm
  • Rear tyre: Continental Competition ProLtd ALX tubular, 25mm
  • Saddle: fi’zi:k Ares, carbon shell, k:ium rails
  • Seatpost: BMC Aero Post
  • Bottle cages: Elite Sior Mio (1)
  • Other accessories: SRM PowerControl 7 computer, RaceWare Direct Raised SRM TT computer mount

Critical measurements

  • Rider’s height: 1.80m (5ft 11in)
  • Rider’s weight: 70kg (154lb)
  • Saddle height from BB, c-t: 754mm
  • Saddle setback: 52mm
  • Seat tube length (c-t): 503mm
  • Tip of saddle nose to centre of bars (next to stem): 560mm
  • Saddle-to-elbow pad drop: 125mm
  • Frame stack: 480mm
  • Frame reach: 393mm
  • Weight: 8.67kg (19.11lb, with computer, without bottle)