FiftyOne Bikes founder Aiden Duff says they’ve built enough custom road bikes for different riders that they average 10 unique bike designs every month, more than many brands do in a few years.
Now, he’s distilled all of that data into the new FiftyOne Sika, a top-level road bike designed for real riders, not professional racers. It’s still high performance, but with clearance for 40mm tires, confident handling, and a less extreme riding position.
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But, Duff says that doesn’t make it an “endurance” bike, that it’s very much a performance road bike. It gets aero touches, high bottom bracket stiffness, and is very light. Claimed weight is just 690g!
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That makes sub-7kg complete bike builds, with pedals, entirely possible. Duff said being ultra lightweight wasn’t the goal, but a careful selection of high-level Toray fibers let them hit their stiffness goals, use aero-optimized tube shapes, and still make it really light.
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Ride quality is enhanced by the larger tires (if you want them, it works great with 28-32mm tires, too), plus a standard round 27.2 seatpost and added fork compliance. Their “real rider” geometry gives it a bit shorter reach and chainstays that are a few millimeters longer than what you’d find on a race bike.
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The one-piece bar/stem is their first in-house cockpit design. It has NACA airfoil shaping with a slightly 3º backsweep to make it and you a little more aerodynamic. All cables and hoses run internally for a full stealth look.
Lastly, it uses a T47 threaded BB and a UDH hanger for solid future component compatibility and easy service.
Framesets retail for priced €4,500 / $4,500 / £3,950. They come with a lifetime warranty and are UCI-approved.