Before I was born my father bought a unicycle at a garage sale but no one in my family learned to ride it. When I was around fourteen years old I decided that I would learn how. After about 8 months of off and on hard work I could finally ride it forwards indefinitely. Here are the five basic steps I used to learn how to ride a unicycle (and I'm obviously still alive).
Believe it or not this is probably the most important step to learning how to ride a unicycle. There are a few things you will need to look for.
First thing you will want is a long wall or fence with a flat and smooth surface right next to it (schools and other large buildings tend to be good places to look). Grass can work, but if it is at all uneven then it will be harder to pedal smoothly and evenly without jerking. The longer the wall/fence the better and try to find something tall enough where you can remain in a comfortable upright position without leaning forward too far.
You'll also want a wide open (once again flat and smooth) surface with something solid to hold on to as well - something like a pole. What also works good is to have multiple objects to hold on to, anywhere from 5 to 30 feet apart depending on how far you can ride at the time. I've found that a basketball court with the baskets on poles in the ground is perfect. This is so you have something to practice riding naturally (balancing and not holding on to anything). One pole is all you need, but having multiple poles/objects spaced apart will allow you eliminate hours of dismounting and mounting and maximize your time actually riding.
Obviously it is important to first learn how to get on the unicycle safely. Don't expect to be able to do this without holding on to something. Chances are you'll actually learn how to ride it before you learn how to get on with no hands! Almost any type of riding surface will do at first and make sure what you're holding on to is solid. Something soft like grass will be easier than concrete at first because it will help keep the unicycle steady. Once you get better at mounting and begin riding try to find a hard and flat surface like concrete that is more suitable for riding.
Start by standing next to the object you will use to steady your balance and hold the unicycle upright and centered (as it would be when riding it) directly in front of you. Decide which foot feels most comfortable to get on with first - it will probably be the foot/side you normally mount a bicycle with (for righty's probably the left foot). Turn the wheel until the pedal on the side of your leading foot is at the bottom, as low as it goes (and the other pedal is at its highest). So if you are a righty your left pedal should be at its lowest. Without moving the wheel/pedals, bring the seat down and push it up in between your legs so you are nearly sitting on it yet still standing with complete balance on the ground. While holding on to your solid object for balance, place your leading foot on the pedal at its lowest point. Mostly all of your weight should still be on your leg standing on solid ground and you should be relatively comfortable in this position.
To complete the mount, take a small jump up and forwards using the leg still standing on the ground. Instantly after you jump, begin to shift weight onto your other lead foot that started on the pedal. Since this pedal is at its lowest point, your weight on it should keep the wheel very steady. Hold on to your solid object to help maintain your balance and bring the foot that you used to jump onto the other pedal. Only put weight on the pedal all the way down (your leading foot), on the seat, or on the solid object you are using for balance. Putting weight on the pedal that is at its highest could cause you to push the pedal forward/backwards and cause the unicycle to roll out from under you either to the front or the back.
As you practice more you will learn how to slide your bottom comfortable onto the seat in the process. In the meantime you will probably need to hold on to something as you move it more under your weight and in a comfortable position. Before trying to ride, make sure you have these steps and principles somewhat mastered.
To dismount basically do the mounting process in reverse.
Once you can mount the unicycle without much of a problem it is time to start riding it! Go to the place with the long wall/fence you found for step 1. Use the wall/fence to mount the unicycle and begin by slowly pedaling forward as you use your hands to maintain your balance and catch yourself if you start to fall.
The key is to practice good posture in a natural riding position while doing this (keeping your back straight and not leaning forward too far). Try to keep as much weight as you can on the seat and on the pedals instead of on the wall or fence you're holding on to. As you practice, try to pedal in a smooth and fluid motion instead of jerking between easy-to-balance positions. In other words, practice balancing for the entire cycle of pedaling and not just the positions that are the easiest (i.e. when one pedal is all the way down).
Practice this over and over going from one end of the wall/fence to the other, turning around, and doing it again.
After practicing for hours you might start to feel that it would be easier to ride without holding on to something. Once you get to this point it is definitely time to start free riding! If letting go sounds scary and you're worried about getting hurt, put on a helmet and maybe some knee/elbow pads and push yourself to take the leap. Even if you're not worried about getting hurt it would be smart to wear a helmet. If you're still scared even with protection then step 5 is for you.
Holding on to the edge of the wall/fence, get into your natural riding posture with all your weight on the seat and pedals. Start to pedal forward and simultaneously give yourself a little push off with your hand. Your instinct might be to pedal very slowly, but you'll find it tends to be easier to balance the faster you're moving. Aim for a comfortable speed that is not too scary but not too slow either - about walking speed is probably good. Keep on practicing this and keep trying to go farther and beat your record.
This is the perfect time to use the location with poles spaced apart. Try to ride from pole to pole so you can practice free riding while not having to fall and dismount all the time.
Obviously you will have to practice a fair amount in order to learn how to ride a unicycle. While there is a fair chance you might get some small cuts and bruises from falling, the chance of getting seriously injured while learning how to ride a unicycle is rather small. In fact, learning to ride a bike is more dangerous since you can go a lot faster. The worst of my injuries in all of my learning and riding has been banging my shin with a pedal when I fell once. Most of the time when you fall you simply just land on your feet. That said, as long as you wear a helmet along with maybe some elbow, wrist, and knee pads, you actually have nothing to worry about.
Few things grab peoples attention more than seeing someone riding a unicycle. If you enjoy being the center of attention than try learning how to ride a unicycle. For me, it was the reward of learning how to do something few people know how to do and most people think is too difficult. In the end, the real secret is that nearly everybody can learn how to ride a unicycle, it simply takes determination and practice!
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