Copyright Velocomp LLP 2005-2013
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There are four sections to the PowerStroke Window. Each will be described
individually.
WASTED MOTION PLOT
The Wasted Motion Plot shows the motion of the bike, relative to the center
of mass of the rider, both side to side, and front to back, as the cyclist
pedals through a complete turn of the crank.
The amount of bike motion underneath the rider (in inches or cm,
depending on units selection) is shown on the vertical and horizontal axes.
Horizontal is side-to-side; vertical is front-to-back. To help with the
visualization of this movement, handlebars are shown in the view.
The cyclist’s actual motion for the pedal stroke is traced out by the
blue/pink curve. Where the curve is blue, the cyclist is pushing down with
his left leg; pink is right leg.
The more the cyclist pulsates left/right, or front/back, the larger the curve
expands, and the more the handlebars move around. Less wasted motion
will keep most of the curve within the green box (2 watts) of wasted
motion; larger amounts of wasted motion will push the curve into the
yellow, or even red boxes.
If the bike did not move AT ALL underneath the cyclist the curve would
shrink to a pinpoint at the center of the green box, and the handlebars
would be stationary. But zero motion IMPOSSIBLE, because the cyclist can
never be absolutely motionless with respect to the bike.
So, the training
goal is to reduce the size of the curve, getting it consistently within
the green box
.
