Scientists develop program for perfect gear changing

System gives riders ideal balance of power and comfort… they say

by Tony Farrelly   January 13, 2009  

Merida CC5 chainset

A team of Taiwanese scientists have developed a computer algorythm that tells you when to change gear to maintain optimum performance and comfort. The program is intended for novice and utility cyclists and is designed to work with a standard derailleur gear. Shimano developed an automatic gearset and shifting system designed for the same market at the turn of the centry, but that was a very much more complex – simplicity seems to be the key here.

Speaking to the scientists point out that a good derailleur system allows experienced cyclists to move efficiently and feel comfortable, but that's not necessarily the case for untrained riders. The Taiwanese teamed have based their work on the assumption that a fit non-athlete should be able to ride for several hours generating 75Watts without suffering fatigue and at a comfortable cadence of between 60 and 100rpm.

The gear changing algorythm was tested by simulating a 12-speed bicycle and gives a gear shifting sequence which minimises power loss and gear shifts. "By following the sequence, riders can operate the derailleur system more easily," says the team, "Riders will also feel comfortable because all gear-ratios can be used, and gear-shifting actions will be smoother." The computer will automatically adjust to riding conditions, satisfying the human element.

ScienceDaily concludes that: “It would not be hard to imagine extending the concept to entirely automatic mechanical gear-changing system.” It certainly wouldn't because Shimano have already done it – it's called the Shimano Cyber Nexus.