Wild Concept to Reality

The stunning Cannondale CERV bike is a radical chainless, forkless design that features a dynamically adjustable headset that moves both fore/aft & up/down, putting the rider in an optimal position based on terrain. The headset translates forward & down for a clean, low-drag position when descending. When climbing, it moves up & back, creating an upright position for maximum leverage on the crank. It’s all made possible by an ingenious single-sided swing arm in place of a traditional fork.

Designer: Priority Designs


  • honkey says:


  • Bo says:

    Direct Drive Gearing Issues: The friction in the high speed gear-up to the final gear to rear wheel are very likely to be many times higher in those losses than a chain drive and thus not practical for any serious rider. Hence the design will have to retreat back to chain and derailleurs, which could work.

    30mph = 44 ft/sec w/2ft dia gear/wheel ≈ 7 rev/sec = 420 rpm. If you have a 10/1 gearing ratio the small driving gear must be doing 2000-3000 rpm or more. Gearing up about 50-100 to 1 to do this is very inefficient.

  • Bo says:

    AND…if it is a direct shaft drive to a geared rear hub then there are miter gears at a minimum and then a full gearbox to change ratios. Friction will kill the efficiency. It is back to chain drive.

  • jesus says:

    i have my doubts about the eficiense, but looks good

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