My Bike
Is it a robot? Is it a motorbike? Nope – it’s James Cunnama’s super-fast, super-aero, Ironman-ready Cervélo P5X. Feast your eyes on it.
At the time of writing, professional triathlete James Cunnama was in the final phase of his preparation for the annual Ironman World Champs in Kona on the Big Island of Hawaii, which takes place on 14 October. The 34- year- old South African will tackle the 180km bike leg aboard this spaceship: Cervelo’s freakishly aerodynamic P5X.
Frame and Fork Rocket Ship Radness Cunnama was one of the first triathletes to race Cervélo’s flagship TT frame, the P5X. After a year, Cunnama says he’s become ‘embedded in the bike’.
With a PB of 7 hours, 51 minutes, 2 seconds at the Frankfurt Ironman in July, and a winning performance a few weeks later at Hamburg’s inaugural Ironman, there’s no denying he and his carbon-fibre rocket ship share a fabulously fast partnership.
With its top-tube curving around the front wheel to create a single aerodynamic shape, the P5X is as slippery as they come.
The ‘X’ signifies that the P5X is not UCI-legal (no double triangle, for a start). However, it has received the green light from the WTC and ITU triathlon organisations.
Riding a 56cm frame, Cunnama opts for a slightly higher front end, with the position favouring comfort over absolute aerodynamic performance. The ‘higher’ position also helps to open the hip angle, allowing his glutes and hamstrings to retain some energy and flexibility for the run leg. Wheels and Tyres Enve-ously Fast Cunnama achieved his impressive Hamburg win aboard a pair of Enve SES7.8 disc rims laced to DT Swiss 240 hubs. 12mm thru-axles (with tool-free quick- releases) beef up stiffness, while the disc-specific rims are lighter and wider than their rim- brake cousins.
Cunnama hasn’t suffered a single flat (touch wood) while running Schwalbe Pro One tubeless tyres – that’s 13 months and counting! Each filled with 30ml of Schwalbe’s Doc Blue sealant, the 25mm Pro Ones are pumped to 6.7bar up front and 7bar at the rear. These relatively low pressures, Cunnama says, add a ton of comfort for the bike leg, helping him to save energy. Groupset Mixed Bag The P5X’s drivetrain is a mix of Shimano Dura Ace Di2 (front and rear derailleurs, 11-25T cassette, shifters and brakes); CeramicSpeed (oversized pulleywheel system, bottom bracket and UFO chain); and Rotor (170mm 2INPower crankset with power meter, and 54-39T Q-rings).
Cunnama has discovered that a 170mm crank generates an ideal hip angle at the top of his pedal stroke, translating into more energy for the run. The P5X gets a new chain before each major race, so that’s four or five every year.
Cunnama is a huge fan of disc brakes on TT bikes – something of a rarity at present – as they offer more power, safety and control. The P5X is fitted with flat- mount TRP Hy- Road disc brakes that are cable- actuated, but offer hydraulic modulation thanks to an additional reservoir on each calliper – this hybrid design is necessary, as hydraulic TT brake levers are not yet available. Parts Old and New A significant feature of the P5X – which Cunnama describes as ‘ life- changing’ – is its cockpit adjustability. Brilliantly engineered, it allows easy setup tweaks, and is effortlessly disassembled for travel and storage.
An XLab Torpedo front bottle, XLab Sidekick carbon cage and XLab Gorilla carbon cage provide Cunnama’s hydration solution, while the P5X frame’s ‘stealthbox’ takes care of tool/ tube storage.
Following the ‘ if it ain’t broke, don’t fix it’ philosophy, Cunnama still uses a Cobb Plus saddle bolted to a P5X seatpost. Pedals are Shimano Dura Ace; bar tape is Cervélo black cork. A Garmin 510 is attached to a universal stem mount, stretched out between the handlebar extensions.