It is easy to balance on a bicycle when it is moving,but not when it is not moving. Why?

Answer 1

When you sit on a bike, the front/back balance is taken care of by the position of the wheels and your body forming a stable triangle. This is not true of sideways balance.

In order to be able to balance sideways it is neccessary to move the bike sideways under you in order to compensate for gravity wanting to pull you over. Sideways movement of the bike can only be accomplished when the front wheel is turned. If the bike is not moving, the turning of the front wheel does nothing useful. When the bike is moving, the angle of rotation of the front wheel causes some of the forward momentum to be translated into a new vector which is partially sideways.

If you are finding yourself falling over to the left, turning the front wheel to the left will cause the bike to move left under you, restoring you to near equilibrium.

Actually it is not impossible to balance on a bike when it is not moving. Turning the front wheel with the rear brake on does give a very small amount of sideways motion which can be used to correct balance.

Correction: The gyroscopic argument is inappropriate here because it applies to wheels in motion. It is not impossible to balance on a stationary bike, therefore the answer cannot be based on the gyroscopic effect. Note that the questioner also refers to it not being easy to balance on a non-moving bike, and does not say it is impossible.

For very similar reasons, the argument about inertia also does not apply.

I have seen people at traffic lights on bicycles who rock the bike backwards and forwards with the wheel turned in order to maintain balance and not put their feet down. In this situation the wheels are not turning fast enough for there to be any appreciable gyroscopic effect, and the net inertia is zero, yet their balance is maintained.

Answer 2

Your avatar reminds me of somebody who just sent me an ecard...

To answer your question, it's not gyroscopic force. The answer is the constant small steering corrections you make when moving. You can prove this when riding slowly, you'll notice that you have to make larger steering inputs to move the tire's contact patch under you.

Think of it like balancing a pole vertically on your fingertips - you have to more around underneath the pole to keep it balanced, its' never completely still. Same idea with the contact point where your tires touch the ground.


Scott

Answer 3

you have momentum plus the spinning wheels have a gyroscopic effect as mentioned above. this has more to to with physics, but basically, when the wheel moves, its stable. if you've ever spun a wheel in your hand (if you hold each end of the axle and spun it around) it does'nt flop all over the place.

if you can master the trackstand (staying balanced while not moving), then you got skill.

Answer 4

I would relate this answer with physics as newton's third law says "to every action there is equal and opposite reaction so when the cycle is not moving there no action produced that is why there is no reaction and due to actin and reaction force there is no balance between us and the cycle n hance we tend to fall off.

Answer 5

The spinning wheels create a gyroscopic effect.

Answer 6

The wheels act like gyroscopes. They want to move in a straight line. ("A body in motion tends to remain in motion").

Answer 7

there's a gyroscope that demonstrates the idea of centrifugal stress. even as the wheels are turning, the stress is thrown vertically, preserving the motorbike upright. even as the wheels are stopped, gravity takes over, ensuing in skinned knees.

Answer 8

the acceleration of your wheels creates a force that is perpendicular to your wheels, in equal and opposite directions, stabilizing you

Answer 9

becoz. at that time cycle is in motion and acc. to first law of motion it tends to remain in that state .......
but when we stop it it take time to stop by friction.......

i hope u want this answer only.

Answer 10

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