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Actually they don't. Today you can get belt driven bikes, or shaft driven bikes. And back in the days there used to be direct-drive bikes with the pedals solidly bolted to the wheel axle. There's also been a treadle-driven bicycle.

But direct-drive makes it awkward to find a comfortable riding position, and to get any speed you end up with really big drive wheels. Treadle-drive needs more moving parts interacting. Transmission shaft bikes tend to experience"wind-up" when being pedalled hard, and quite a bit of power is lost in the type of gearing that is needed in the power transfer train. Belt drive can be quite good, but as the belts can't be opened or cut to size, these bikes usually need special frame designs.

A chain is easier to work with than a belt, has simpler mechanics than a treadle, less mechanical losses than a shaft, and better speed/fit options than a direct drive, so it became the most common design.

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12y ago
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9y ago

To move the pedalling position from the hub of the wheel to a place where it'd work better. Also to provide a gear ratio allowing the rear wheel to turn faster than the pedals.

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14y ago

to reduce wear and unwanted friction.

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Q: Why the chain of bicycle is to be greased?
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What maintenance should you do on a bicycle?

Answer: LUbricate the Chain (Not using WD40) Keep Tyres Inflated Keep All Bearings adjusted and greased.

What happens when you dont keep the chain or gears on your bike greased and why does that happen?

if you don't keep your chain and gears on your bike greased it will rust and come off.

What does a bicycle have to make it move?

a chain

Is a bicycle chain a inclined plane?

no it is a lever

What are not examples of inclined planes?

Bicycle chain

Velocipede the 1885 addition of a chain drive created what two-wheeled vehicle?


What does a bicycle chain cover do?

It protects the chain from rain and road grime and it protects your trouser legs from chain gunk.

A bicycle chain is an example of what simple machine?


A bicycle chain is an example of what type of simple machine?

The chain is wrapped around a cogwheel, which could be described as a pulley.

Would you find a derailleur on a bicycle train or a car?

A deraileur is the device that shifts the chain to different cogs on a bicycle.

What part of a bicycle makes the bicycle go?

The pedals, crank, chain, sprockets, and wheels. Along with the rider, they all work together to make the bicycle go.

What is a bicycle chain?

It's a type of chain known as a roller chain that is used to transfer power from the cranks to the rear wheel of the bike.