Geoff Kabush (Maxxis-Rocky Mountain) arrived at the weekend's UCI races in Boulder, Colorado with a new carbon fiber cyclo-cross chassis that's not listed in the Rocky Mountain catalog. According to team head mechanic Gary Wolff, Rocky Mountain supplied a few of these frames just for Kabush and might turn them into a production item but for now, they're team-issue only.
Kabush's frame features most of the features common to modern 'cross chassis: a tapered front end, internal cable routing and what look to be carbon rear dropouts. We don't have a frame or fork weight available – and Wolff didn't know it – but total weight on Kabush's complete bike is a very competitive 7.55kg (16.64lb).
Easton add even more carbon fiber to the mix with sub-1,200g EC90 SLX tubular wheels, their EC90 seatpost with molded carbon shaft and clamp, and their semi-anatomic EC90 SLX handlebar, and even TRP get into the composite mix with their CR950 cantilevers.
TRP have released a slightly wider-profile CR959 SL cantilever to better match the power of Avid's Shorty Ultimate lever but Geoff Kabush sticks with the original CR950
Shimano provide a complete Dura-Ace drivetrain and mechanical transmission, including the shift/brake levers, both derailleurs, the chain, 12-27T cassette, and forged aluminum crankset with 'cross-specific 39/46T chainrings. Despite Kabush's large-sized hands, the lever reach is brought in just a touch for easier braking and shifting while in the drops.
Kabush is sponsored by Maxxis but the company don't make 'cross tubulars and at this level of the sport, they're a virtual necessity to even think about being competitive. The team have gotten around the problem by sending stock Maxxis clincher tires over to tubular tire experts Dugast, where the treads are carefully removed and then hand-glued onto a supple 32mm-wide cotton casing.
Kabush races on custom Dugast tubulars covered in Maxxis treads. He uses the Raze for most days
The end result is the tread that Kabush wants but with the suppleness he needs. For most courses, Kabush says he runs the Maxxis Raze tread with its fast-rolling but reasonably openly spaced square knobs but he also has a set of custom Mud Wrestler tubulars for sloppier courses.
Rounding out the mix are a Fi'zi:k Antares K:ium saddle and padded tape, an FSA integrated headset, CrankBrothers' feathery Eggbeater 11 pedals, and Shimano cables, housing and sealed end caps.
Kabush uses an alloy stem but a carbon bar on his Rocky Mountain carbon fiber 'cross bike
Complete bike specifications
- Frame: Rocky Mountain Solo Carbon prototype
- Fork: Rocky Mountain Solo Carbon prototype
- Headset: FSA Orbit integrated
- Stem: Easton EA90, 120mm x 0°
- Handlebar: Easton EC90 SLX3, 44cm (c-c)
- Tape: Fi'zi:k dual:tape
- Front brake: TRP CR950 w/ Easton carbon-specific pads by SwissStop
- Rear brake: TRP CR950 w/ Easton carbon-specific pads by SwissStop
- Brake levers: Shimano Dura-Ace STI Dual Control ST-7900
- Front derailleur: Shimano Dura-Ace FD-7900
- Rear derailleur: Shimano Dura-Ace RD-7900-SS
- Shift levers: Shimano Dura-Ace STI Dual Control ST-7900
- Cassette: Shimano Dura-Ace CS-7900, 12-27T
- Chain: Shimano Dura-Ace CN-7900
- Crankset: Shimano Dura-Ace FC-7900, 175mm, 39/46T
- Bottom bracket: Shimano Dura-Ace BB-SM7900
- Pedals: CrankBrothers Eggbeater 11
- Wheelset: Easton EC90 SLX tubular
- Front tire: Custom Maxxis Raze tread on Dugast tubular casing, 32mm
- Rear tire: Custom Maxxis Raze tread on Dugast tubular casing, 32mm
- Saddle: Fi'zi:k Antares K:ium
- Seatpost: Easton EC90 Setback
- Other accessories: Shimano SP41 derailleur housing and sealed end caps
Critical measurements
- Rider's height: 1.90m (6ft 2in)
- Rider's weight: 75kg (165lb)
- Saddle height, from BB (c-t): 775mm
- Saddle setback: 75mm
- Seat tube length, c-t: 585mm
- Seat tube length, c-c: 540mm
- Tip of saddle nose to C of bars (next to stem): 570mm
- Saddle-to-bar drop (vertical): 50mm
- Head tube length: 180mm
- Top tube length: 570mm
- Total bicycle weight: 7.55kg (16.64lb)