Bike Check: Turning an Orbea Orca Aero into a 10-mile TT weapon
This is no stock build. We break down the marginal gains, massive chainring, and clever component choices behind a road bike optimised for pure time trial speed.
An aero road bike is already a specialised tool, but what happens when you take that platform and sharpen it for a single purpose? That’s what we have here with this Orbea Orca Aero, a bike methodically tweaked and tuned with one goal in mind: laying down a fast 10-mile time trial.
This isn't just a case of slapping on some deep wheels; it's a deep dive into drivetrain efficiency, biomechanics, and sweating the small stuff.
The starting point is Orbea's latest Orca Aero frame, which the brand claims saves 5 watts at 50 km/h over its predecessor. But that’s just a baseline, as nearly every component choice is a deliberate step away from the stock configuration.
The Drivetrain Diet
The most striking modification is the move to a 1x drivetrain, ditching the front derailleur and inner ring entirely. In their place sits a single, enormous 58-tooth chainring from AeroCoach. "But I've gone for a 58, which sounds massive, because it is," the presenter admits.
This isn’t about chasing a bigger top gear, as his usual setup is a 54/40-tooth combination. The real reason is drivetrain efficiency: using such a large ring allows for a straighter chainline by spending more time in the middle of the cassette.
A straighter path from chainring to cog reduces friction. As he notes, lab tests have shown a combination like 58-16 saves "a considerable amount of watts" over a more cross-chained equivalent like 52-11. It's a classic marginal gain, trading 2x versatility for raw efficiency.
The pursuit of efficiency doesn't stop there. The rest of the drivetrain has been given the full low-friction treatment, with a CeramicSpeed oversized pulley wheel (OSPW) system, a CeramicSpeed BB Alpha bottom bracket, and a chain treated with Cyclowax Race Wax. It’s a holistic approach to minimising mechanical drag, right down to a chain so clean it passes the "clean finger test."
A Short-Crank Experiment
Bike fit trends have been leaning towards shorter cranks for years, and this build embraces that philosophy. The presenter has swapped his usual 170 mm cranks for a 165 mm Shimano Dura-Ace set. "I thought I should do an experiment on myself and actually try them," he says.
The logic is sound, particularly for aggressive aerodynamic positions. As he explains, "having those shorter cranks and bringing the saddle forward means that I can open up my hip angle a little bit."
In simple terms, this means less bunching up at the top of the pedal stroke, making it easier to breathe and produce power while bent low over the bars. It's a key enabler for a sustainable aero position, where the real time savings are found.
Cockpit and Contact Points
That aero position is supported by a few other deliberate choices. The brake levers are turned inwards slightly, a popular modification that creates a more comfortable and narrower hand position when riding on the 'aero hoods'. Even the computer is a nod to aerodynamics, with a Wahoo Bolt chosen for its smaller frontal area compared to larger units.
Perched atop the seatpost is a Selle Italia SLR Boost S3 saddle, specifically what he calls the "fancy-pants 3D printed one." While 3D-printed saddles offer comfort benefits, in this context it’s another piece of the puzzle that allows the rider to hold that aggressive, hip-rotated position.
Wheels, Tyres, and Final Touches
The bike rolls on a set of Elite Drive SL 58D wheels with a 58 mm rim depth, a sweet spot for aerodynamics without being a handful in crosswinds. They feature carbon spokes, which the manufacturer claims makes them lighter and torsionally stiffer, with a quoted weight of 1,400 g for the pair.
They’re shod with 28 mm tyres, reflecting the modern understanding that slightly wider tyres can offer a net benefit in rolling resistance and aerodynamics on wide rims.
Even the smallest details have been considered. The Orbea's stock integrated bottle cages have been removed entirely, as for a 10-mile effort they represent pure drag. The presenter’s reasoning is blunt: "Most bikes are faster without bottles and cages."
He's also fitted high-airflow Topeak Fast Flow tubeless valves and measures power via dual-sided Favero Assioma Pro SL pedals.
Ultimately, this build is a fascinating case study in specific optimisation. It’s a clear statement that for a short, flat-out effort, "aero trumps weight." While a 58-tooth chainring might be overkill for most of us, the principles at play—improving chainline, opening the hip angle with shorter cranks, and minimising frontal area—are lessons any rider can apply in their own quest for speed.
Build Sheet
- Frame: Orbea Orca Aero
- Wheels: Elite Drive SL 58D (58 mm deep)
- Tyres: 28 mm
- Groupset: Shimano Dura-Ace crankset (165 mm), AeroCoach 58t 1x chainring, CeramicSpeed Oversized Pulley Wheel system, CeramicSpeed BB Alpha bottom bracket
- Finishing Kit: Selle Italia SLR Boost S3 saddle, Favero Assioma Pro SL dual-sided power meter pedals, Wahoo Bolt computer, Topeak Fast Flow tubeless valves
It’s a clear statement that for a short, flat-out effort, "aero trumps weight."