Thursday, January 25, 2001
Bethel, CT--Mountain bikes with microchips and mini-motors may seem
like overkill, but Cannondale's new automated shock lockout mechanism is hitting
the racing circuit. The electronic lockout feature engineers developed, called
the Lefty ELO(tm), offers all the advantage of manual systems, without any of
the drawbacks, and is now available at dealers.
Push-button operation at the rider's hand effectively eliminates all handling
control risk because the rider never needs to remove a hand from the handlebar!
One touch of a button activates the lockout; a second touch deactivates it. Such
ease-of-use means riders can lockout far more frequently, conveniently, and
precisely than with a manual system. And no matter what the rider's skill level,
it takes less than 1 sec to lock or unlock the shock.
But designing an automated damper lockout mechanism that fits within existing
space, size, and weight constraints proved somewhat daunting, according to James
Gardner, project engineer at Cannondale. That is until engineers discovered the
smoovy motor from RMB (Ringwood, NJ; www.smoovy.com). Ultimately, engineers were
able to fit an 8-mm motor, a 1:25 ratio gearbox, and a linear screw shaft inside
the shock as an integral part of the Cannondale valve system.
With the base mechanical design decided, engineers focused on system
performance. They had to balance valve actuation time with the system's voltage
and the current draw and motor capability. "We gave equal weight to system power
and the battery target life of 3 months," Gardner says. "Smoovy gives us so much
smoothness and efficiency, that we make out on all counts. Using a standard 9V
battery, we get the desired speed and torque, and the battery lasts 6 months
with average use."
Engineers arrived at the desired actuation time through design iteration,
varying lead screw pitch, motor starting ramp, system voltage, and oil
characteristics. Then they designed the electronics packaging such that the
battery and controller slide in the top of the fork, leaving the battery readily
Racers tested pre-production ELO prototypes at World Cup races last spring.
Then ELO made its Olympic debut in Sydney with all 7 of the Volvo/Cannondale
riders using totally new ELO-equipped super light forks. Christoph Sauser, a
Swiss, even won a bronze medal. For more information visit www.cannondale.com/bikes/elo.html.