Flipping the script

Based in Dublin, Ireland, FiftyOne Bikes is a manufacturer of hand-built custom road bikes and factory-built gravel bikes. Every bike is made to their exacting standards and designed to the needs of each individual rider.

The Assassin is a progressive gravel bike with dual (front and rear) flip chips. Its adjustable geometry creates capability in place of compromise, allowing you to tailor the handling to how you ride. Thanks to the multiple geometry options, the Assassin is a solid choice for explorers, shredders, racers, bikepackers and anyone else who loves getting away on the road less traveled.

Flip chips explained

The Assassin’s flip chips are the keys. Rider preferences on bike handling vary and gravel roads vary even more, so one size does not fit all. The solution is usage-tailored handling, giving you confidence whether you want to race, explore, tour or shred.

Check out Nicolas Roche’s custom FiftyOne

At the rear, two chips offer three axle positions, adjusting the effective chainstay length and overall wheelbase in 5 mm increments. Go shorter for more agility, go longer for extra stability, or take the middle option (like below) if you want a balance of each.

At the front, the chips offer two positions, high and low. The ‘low’ position gives a longer trail and slacker head tube angle, suited to more aggressive riding on more challenging terrain; the ‘high’ position creates a shorter trail and a steeper head angle, ideal for gravel races or rides on back roads and less rough terrain.

• Long and Low = rugged terrain, more MTB feel, likely on 45mm+ tires
• Short and High = milder gravel, more road bike feel, likely on 38mm tires
• Experiment to find the combination that suits you and your riding best

The Assassin’s flip chips allow you to tailor the handling to suit your riding. They are not designed to offset a switch between 700c and 650b tires because that can only be done for specific tires as outer diameters vary with tire size.

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