| Well, I'll take a shot at this since I just had it done a few weeks
ago... hopefully, more knowledgeable folks will correct my errors! :^)
The RAD setup is a "pedal" that has freedom of lateral movement on the
pedal cage into which you slide the clipless cleat. A rod extends
outward from the pedal spindle (perpendicular to the bike frame), and
another from the cage. In my case, they mounted the pedals on their
FIT-KIT bike, set up the frame to the measurements on my real bike, and
had me climb on. They applied some wheel tension (standard mag trainer
type setup), and had me pedal for several minutes until I was
comfortable and somewhat warmed up. Apparently this is needed because
the alignment of ankles and knees changes as things warm up?
The cleat is lightly attached to the shoe - tight enough not to flop
around, but loose enough to move with a little effort.
As you rotate your heel in and out around the point where your foot is
connected to the pedal by the cleat, the rod extending from the pedal
cage pivots fore and aft, crossing back and forth over (but not
touching) the rod extending from the spindle. As you pedal, your feet
theoretically fall into their normal alignment since they can move as
they want.
The person doing the fitting periodically has you stop pedaling and
moves the cleats on your shoes to directly line up the two rods one
above the other. Eventually, depending on how good the fitter is, and
how much movement you have in your feet, you get lined up so that as
you pedal the rods stay in "perfect" vertical alignment. They tighten
the cleats, put you back on the test unit and have you ride again. If
everything is still aligned you are done. Otherwise, the process gets
repeated until things fit.
However, in some cases there is enough movement during the stroke that
it can be a problem being locked in. I was told by the people doing
the fitting that in some cases they have stopped in mid fitting and
recommended that the person buying the pedals should consider a pedal
with some built-in lateral movement to protect the rider's knees.
Least ways, thats how they did mine... So far, they've been SUPER. No
knee pain, no strain, and measurably faster!
good luck,
Dave
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