Pro bike: Katie Compton’s Trek Boone 9 and Boone 9 Disc

Disc and rim brake options plus impeccable prep for the 10-time US champion

Katie Compton is without doubt the most successful American cyclocross racer ever with nearly two dozen World Cup wins, three World Championship medals, two overall World Cup titles, and a dominating 10 US national titles. Not surprisingly, Trek Factory Racing showers the affable Coloradan with an enviable level of equipment support so she can be prepared for any course conditions, anywhere, at any time.


While many racers are locked into using either rim brakes or disc brakes, Compton has Trek Boone 9s set up with both. Compton and her husband/mechanic Mark Legg-Compton don’t travel the globe with both simultaneously, though. Compton generally prefers the lighter and less powerful rim brake bikes for the rigors of European racing, while the disc bikes are usually reserved for racing on home soil.

Katie compton (trek factory racing) also has a stable of disc-equipped trek boone 9s, these with custom stars-and-stripes paint jobs:

Compton gets to choose from disc or rim brake bikes at will

Both bikes, however, incorporate Trek’s groundbreaking IsoSpeed design, which uses a mechanical pivot at the seat cluster that allows for much more flex (and thus, comfort and rear-wheel traction) at the saddle than a conventional frame. Write it off as a gimmick if you insist, but it does work – and remarkably well, in fact.

Compton should be familiar with the Trek Boone 9 chassis at this point, having ridden on it for at least part of last season, but she’ll have to get used to a few major changes this time around. For one, she’s moved away from SRAM Red 22 componentry in favor of Shimano Dura-Ace Di2 – and she’s even moved to Shimano for pedals instead of her longstanding Crankbrothers Eggbeater 11s.

The ‘k’ is for katie, of course, and the ‘c’ is for compton. as for the ‘f’é well, let’s just her middle name isn’t francesca:

The ‘K’ is for Katie, the ‘C’ is for Compton, and the ‘f’… isn’t for Francesca

Compton has used Shimano’s electronic transmission before, but she’ll have to get used to completely different gearing. Whereas she once preferred WickWërks’ rather small 42/34T chainrings paired with a SRAM 11-26T cassette, she’s now on a 12-28T cassette with more conventional 36/46T chainrings (including CNC-machined outer chainrings that Shimano currently only provides to sponsored racers).

Save for the obvious differences in brake hardware, both sets of bikes are otherwise identically outfitted with ultralight Bontrager integrated carbon fiber cockpits and a collection of tires from famed French tubular maker FMB. Naturally, Bontrager supplies the wheels as well, which include the company’s versatile Aeolus 3 D3 carbon tubulars on the rim brake bike. Bontrager doesn’t currently offer disc-compatible carbon tubular wheels, so Compton’s are custom built using Aeolus 3 D3 rims and Affinity Pro hubs.

As bontrager doesn’t currently make a disc-compatible carbon tubular wheelset, these are custom built using hubs borrowed from an affinity pro wheelset:

Custom wheels are built for her Trek Boone 9 Disc

As for pedals, Compton is now on Shimano’s prototype XTR model, which uses a specially milled-down body as compared to the standard XTR Race version for better mud clearance. While these may be appreciably heavier than the Crankbrothers pedals Compton used for years, Legg-Compton says the bigger platform – and more reliable starts that come along with it – were well worth the extra grams.

Compton’s bikes may be nice to look at (and they obviously can go very, very fast) but what’s always striking each time we profile one is how impeccably they’re prepared. Legg-Compton says he’ll spend up to three days building each one, thanks in no small part to the fanatical attention to detail. Legg-Compton has a strict ‘no zip-ties’ policy, for example, so the brake hoses on the Boone 9 Discs are secured with a mix of fishing line and Krazy Glue. Meanwhile, heat shrink tubing is used for the cable ends on the rim brake bikes and to pair the Di2 wires to the rear brake lines.

Details, details – the brake cables are finished with bits of heat shrink tubing and secured with a mix of fishing line and krazy glue:

Look closely and there’s an incredible attention paid to detail

We’ve often noticed that Legg-Compton is quite a fan of glue in general. More Krazy Glue – plus a bit of Colorado sand – is used to provide some much-needed texture on the Di2 shifter buttons while frame holes are sealed with clear silicone adhesive. Although it doesn’t look especially tidy (sorry, Mark!), it does feel fantastic – and not unlike the similar mod we proposed a couple of years ago.

Regardless of how it looks, it certainly works well. More importantly, Compton is putting the new bikes to good use with a very strong start to this season with perhaps a strong World Cup run to follow.

For better grip on the shimano dura-ace di2 shift buttons, husband/mechanic mark legg-compton has added some texture courtesy of a krazy glue and colorado sand:

A mix of Krazy Glue and “Colorado sand” adds some much-needed texture and grip to the Shimano Dura-Ace Di2 shifter buttons

Complete bike specifications

  • Frame: Trek Boone 9, 52cm
  • Fork: Trek IsoSpeed Cross
  • Headset: Cane Creek IS, 1 1/8-to-1 1/2in tapered, integrated
  • Handlebar/stem: Bontrager XXX Integrated, 400mm (c-c) x 120mm x -7°
  • Front brake: Shimano BR-CX70 w/ Bontrager carbon-specific pads
  • Rear brake: Shimano BR-CX70 w/ Bontrager carbon-specific pads
  • Brake levers: Shimano Dura-Ace Di2 STI Dual Control ST-9070
  • Rear derailleur: Shimano Dura-Ace Di2 RD-9070
  • Shift levers: Shimano Dura-Ace Di2 Dual Control ST-9070 w/ SW-R610 ‘sprint’ shifters
  • Cassette: Shimano Dura-Ace CS-9000, 12-28T
  • Chain: Shimano Dura-Ace CN-9000
  • Crankset: Shimano Dura-Ace FC-9000, 175mm, 46/36T
  • Bottom bracket: Enduro XD-15
  • Pedals: Shimano XTR prototype
  • Wheelset: Bontrager Aeolus 3 D3 tubular
  • Front tire: FMB Super Mud tubular, 33mm, 17-24psi
  • Rear tire: FMB Super Mud tubular, 33mm, 17-24psi
  • Saddle: Bontrager Affinity Pro
  • Seatpost: Bontrager Ride Tuned Carbon seatmast

Critical measurements

  • Rider’s height: 1.65m (5ft 5in)
  • Rider’s weight: 61kg (135lb)
  • Saddle height from BB, c-t: 695mm
  • Saddle setback: 15mm
  • Seat tube length (c-t): 470mm
  • Seat tube length (c-c): 450mm
  • Tip of saddle nose to center of bars (next to stem): 490mm
  • Saddle-to-bar drop: 45mm
  • Head tube length: 122mm
  • Top tube length (effective): 531mm
  • Weight: 7.31kg (16.12lb)