spins

Dirk wrote:

>> I got the Skill Levels Demonstrated tape and could not tell what a
spin
>> was. (from level 6 - backspin frontspin and spin) What is a spin?
It
>> looks like they’re just turning. I’m not sure what should be
happening.

Beirne wrote:

>Yea, the tape is not very good on this one. I’m not sure if this is
it, but
>The Complete Book of Unicycling describes the spin from an earlier
form of >the levels as doing five circles within a meter’s space.

Here’s my (hundred and) two cent’s worth:

I have done spins on my 24". You will know when it happens. To try to illustrate
what I mean, think about those old wooden rulers with the holes in them for
clipping into a 3- or 5-ring ring binder. I’m sure most people remember sticking
a pencil through the holes and spinning the ruler around. When the pencil was in
a hole close to the center, it was easier to spin it fast because the pivot
point was closer to the center of mass of the ruler. As a spinning object, it
became more evenly balanced.

The same thing is happening in a spin. Imagine riding around in a circle, and a
vertical line drawn up through the center of that circle. As you start riding
smaller circles, shortening the radius and leaning further into the turn, soon
you get a point where that vertical line starts traveling through your torso. At
some point that vertical line is going up through your body quite close to your
own center of gravity. Then part of your body (your head and at least one of
your shoulders) is on one side of the vertical line and starts to balance out
the part on the other side. While your wheel is doing a circle on the ground,
your head is doing another circle in the air, the same direction but 180 degrees
out of phase.

Suddenly you are turning quite fast, the tire is really scraping and it feels
like you are pedaling twice as fast as you should be. I think the wheel actually
does one complete revolution for each 360 degrees turned. Almost before you can
stop you have made two or three revolutions. If you look down at the ground in a
spin you get very dizzy.

I start a spin by holding my arms straight out in line with my shoulders, then
twist at the waist in the direction I want to spin (to the left works best for
me–is this Coriolis force or just personal preference?) and tilt my arms so the
hand on the inside of the turn points at the ground and the one on the outside
points up in the air. I lean my body forward slightly and sideways slightly. I
keep my back and head in line with the unicycle and it just happens. At first I
chickened out but if you just hang in there and go for it, spins happen. To stop
the spin, untwist the torso, level the arms and lean outward until you are
sitting straight up.

Here’s the funny thing though: when my original uni tire (with a semi-flat
cross-section casing) wore out, I got a Panaracer Uni HP tire with a round cross
section and suddenly I couldn’t do spins. The tire seemed to slide out from
under me if I turned too tight. In fact it kind of goofed up all my riding
because the contact patch was so narrow; the wheel turned (twisted sideways) way
easier than the old one.

I have learned to ride it underinflated to compensate somewhat. Once I got used
to the mushy feel I found I could do all my old tricks plus ones I have learned
since, except for spins. It cushions the bumps and curb drops too. I have an
identical Kenda tire waiting when the Panaracer wears out–I should be able to
spin again.

The backspin and frontspin are doing a half spin to change from forwards to
backwards riding and vice versa. Kind of like a three-point turn in a car,
except you end up going in reverse the same direction. Do it smoothly and it
looks like one move.

When I do this it happens in 4 discrete steps:

  1. riding forward.
  2. a sharp 90 degree turn within 1/2 a revolution, stopping with the pedal on
    the outside of the turn slightly past bottom.
  3. reverse pedal direction, immediately do a sharp 90 degree turn the opposite
    direction of the first turn.
  4. riding backward.