Another way to describe the process: When idling, think of your unicycle as the pendulum of a grandfather clock. The pendulum moves back and forth while the face of the clock remains still. You hands shouldn't sweep around like the second hand of a clock, either (uh-oh, I've overextended my metaphor); use them to make small adjustments to your balance.
The secret to smooth idling is keeping most of your weight on the saddle. Be sure to relax. Remember that the unicycle moves *under* you, while your upper body stays more or less upright. Idling is definitely *not* merely riding back and forth. Also, make sure the saddle is at the proper height -- if it's too low you'll tire very quickly.
Regarding how much of the circle to move the pedals in, people usually start with with about 180 degree revolutions. The goal is to be able to make smaller revolution idles, and, eventually, to be able to sit completely still for short periods of time, make sharp turns and spins, etc.; there are several higher-level skills that are based on the skills developed while idling.
Please take time to learn with either pedal down. You won't want to be able to idle with only the right foot down, for example, as this will limit your future possibilities. If you know how to idle ambidextrously, one foot idling or juggling while idling may become easier to learn. Plus it can occasionally be a bit embarrassing when one's path is blocked and thus one needs to idle, but the "wrong" foot happens to be down at the moment. Also you will need to be able to idle with either foot to pass level 4 of the IUF skill levels.
First-person account by Andy Arhelger:
I have been working on idling for a month now and I thought I would report on my progress. I hope this may help some of you that are try to learn also.
I started 9/2/94 and have been working on this in my basement for 1/2 hour a day 6 days a week. I bought my first unicycle in January 1994 and have been learning since then.
I can now idle for almost as long as I want, at least until my leg muscles get tired. I started by holding onto a post and just tried to let go and go for it. I put my right foot all the way down and use my left foot on top to keep the rocking motion.
It started pretty slow. I didn't feel like it would work at all. As I practiced I learned what was really going on. As you fall to one side you rock forward or back and you must turn the unicycle so it comes back under you. As you then fall the other way you rock again and pull the uni back under you again. To idle you just keep making these constant corrections in either direction.
As you first start you tend to over correct, which causes you to over correct the other way and you loose it pretty quick. As you get better you learn to make smaller and smaller corrections.
I started timing how long I could stay up. At first 2 or 3 seconds was hard. When I got to 10 seconds it started to go faster. Soon it was 15, 20, 30 then 60 seconds. I now can go almost as long as I want.
Pretty soon I got bored and wondered if I could rotate either direction as I was idling. This came with some practice and made the 1/2 hour times more interesting.
I then tried to do a free mount, then 2 full revolutions, stop and idle. This didn't take more than 1 or 2 days to get down. Next I tried to start idling, go forward 1 revolution then stop and idle. The next step was to do a free mount and right into an idle. It only took a couple days for this also and this is how I start idling now, most of the time. This feels real smooth when done right.
I still don't feel like this is real natural and it takes constant concentration for me to stay up. I have tried to juggle while idling but can't get past a dozen throws at best. I found I tend to fall to the right as I do this and have been working more or staying more vertical rather than sort of leaning on the unicycle one way. As part of this I have been working on idling with my hands behind my back. This is pretty hard and I can't go more than 15 seconds or so this way.
This was all done in my basement which has a smooth painted floor. I took the unicycle outside recently and found I couldn't idle on concrete. On the smooth floor I could sort of twist in order to make the corrections, and on the concrete this didn't work at all. It took some more practice outside to compensate for this. Now it works pretty well but still not as good as indoors. More air in the tire would probably help outside.
I also find I tend to stand up on the pedals instead of sitting. Sitting helps because you can use your thighs to press on the seat and help steer. I still need to work on setting down more.
I hope this wasn't too boring for anybody to read and hope it helps somebody else make progress. I would say idling is a rather advanced skill and it sure is harder than people make it look. I have a long winter ahead and will keep working on juggling while idling.
An In-depth Description of Idling:
Background information given prior to an explanation of idling:
A unicyclist in perfect (static) balance has the center of gravity directly over the support point (place where the tire touches the riding surface). However, a unicyclist is rarely in any such perfect balance; his center of gravity is dynamicly shifting forward or backward and left or right of his support point. This sense of imperfect (dynamic) balance is quantified in the following definition.
Definition: Balance Envelope - How far a unicyclist can dynamicly deviate forward-backward and left-right from perfect balance without falling off the unicycle is called his Balance Envelope. So long as a unicyclist stays inside his Balance Envelope, he is in dynamic balance and will not fall off the unicycle. Conversely, the moment a unicyclist goes outside his Balance Envelope, he is (by definition) beyond his ability to remain (dynamicly) balanced and there is absolutely nothing he can do to avoid falling off the unicycle.
An explanation of idling:
One begins to idle by going close to the front or back edge of his balance envelope (establishing a front or back lean). This is done by pedaling backwards or forwards slightly to establish the forward or backward lean required to begin idling.
This description of idling is split into a forward pedal cycle and a backward pedal cycle.
The forward pedal cycle begins with the rider near the front edge of his balance envelope (he is now leaning forward); he pedals forward 90 degrees, moving to the center of his balance envelope (the pedals should now be vertical); he pedals an additional 90 degrees forward, moving his balance envelope near the back edge of his balance envelope (he is now leaning backward).
The backward pedal cycle begins with the rider near the back edge of his balance envelope (he is now leaning backward); he pedals backward 90 degrees, moving to the center of his balance envelope (the pedals should now be vertical); he pedals an additional 90 degrees backward, moving his balance envelope near the front edge of his balance envelope (he is now leaning forward).
Sources include:
The Complete Book of Unicycling by Jack Wiley
Anyone Can Ride a Unicycle by Jack Halpern
Beirne Konarski
Ken Fuchs