Cornering
Two wheels fitted with chasis and engine is not enough to make a motorcycle an overall performer. Beyond the power of engine, design and model there are lot of factors involved in the better handling and manoeuvring the bike. Here the engineering comes to play a vital role for the better stability and handling of the bike. These things are very essential to make a bike to perform its peak apart from factors like engine power, suspension, brakes etc..
Everyone knows what is meant by cornering, It is an activity which is involved while making a turns at corners. Imagine a motorcycle travelling in a straight road without any turns. Now the handling and performance can be judged based on the engine power output as BHP (Brake Horse Power), air resistance and some few factors. But it is not possible to have a straight road or a race track in practical situations. Here the cornering of bike takes place and the performance is judged based on the better cornering abilities of bike.
Now I hope everyone may have some basic idea about cornering. Now we shall see what makes this difference of cornering between these two bikes and what are the natural forces that act on a bike during cornering.
The cruiser bikes have higher centre of gravity this makes cornering little difficult when compared to sports bikes, but they are well suited for long rides. So a bike with higher centre of gravity has to lean less while making a turn.
Camber Thrust
A leaning tyre when rolled will describe an arc. But when attached to a cornering bike, is is not able to follow the natural arc and thus creates a force called the camber thrust. It is the direction which the tyre wants to travel.
Centrifugal force
Rational inertia acting outwards, away from the turn. In case of bikes when we go around a bend, a force is generated which tends to push you out of the turn. This force also helps to keep the bike from falling down into the turn.
Centripetal Force
It is an equal and opposite force to the centrifugal force. It is required to hold the bike in a circular motion. This force is created by the camber thrust of the tyres.
Feedback
The feedback can be anything that a rider feels from his bike when out riding it. This feedback is essential to know how the bike is behaving in turns, the state of road and levels of grip. Many bikers don't know how to interpret these feedbacks and what it represents. Based on the feedbacks the bike's performance can be judged and improved.
Geometry
Based on the better geometry behind the motorcycle the performance of the bike can be drastically improved. These are the factors essential for better handling, cornering and stability behind the motorcycles.
-Centre Of Gravity
The point around where the entire mass of the bike is centralised and balanced. This point plays a vital role in handling and braking.
-Rake
Rake is the angle between the steering axis and a vertical line. It is basically the steepness of the forks. Rake angle is also called as castor angle and plays an important role in the handling characteristics of the bike. A steep rake will give the bike a sharper handling but the stability becomes low (used in sports bikes) whereas a shallow rake (used in cruisers) will enable slow handling but provides better stability.
-Trail
Trail is the distance between the centre of the contact patch of the front tyre and the point where the steering axis hits the ground. When the steering is deflected, it's the trail which brings the front wheel back into line. In sports bikes, the trail will be less so it is less stable but it is easier to turn the bike as compared to cruisers. In cruisers the trail will be longer making it more stable but slower to turn.
-Wheelbase
Wheelbase is the horizontal distance between the front and rear wheel. Longer the wheelbase, more stable the bike will be. Whereas the shorter the wheelbase, more flickable the bike becomes. This suits also to cars.
-Offset
If you draw an imaginary line down the centre of the forks and second line along the centre of the steering axis, the perpendicular distance you get between the two lines is known as fork offset. This is used with rake angle to determine trail.
All these factors are considered while designing a bike which makes it ultimate one both in handling and performance.
Two wheels fitted with chasis and engine is not enough to make a motorcycle an overall performer. Beyond the power of engine, design and model there are lot of factors involved in the better handling and manoeuvring the bike. Here the engineering comes to play a vital role for the better stability and handling of the bike. These things are very essential to make a bike to perform its peak apart from factors like engine power, suspension, brakes etc..Everyone knows what is meant by cornering, It is an activity which is involved while making a turns at corners. Imagine a motorcycle travelling in a straight road without any turns. Now the handling and performance can be judged based on the engine power output as BHP (Brake Horse Power), air resistance and some few factors. But it is not possible to have a straight road or a race track in practical situations. Here the cornering of bike takes place and the performance is judged based on the better cornering abilities of bike.
In MotoGP races the cornering skills play a very important role, the racer have to take better turns for faster exit speeds which in turn improves his lap timing and position. Both the technology and skills of the racer are involved here - the man and machine together. In this we are going to see about the science involved behind better cornering of bikes.
Cornering happens while bending and taking a turn in a motorcycle. Usually every biker may have experienced it while taking a turn. Many factors contribute and decide better cornering abilities of the motorcycle.
To understand it even better ride a sports bike (for example take Yamaha R15, Bajaj Pulsar 220,150 etc) and take a turn at corners during high speeds. In the same way ride a cruiser bike (for example Royal Enfield classic 350, Thunderbird) and take the same kind of turn at the speed similar to the previous one. The difference can be felt now easily by the riders and they will definitely state that sports bikes were easy to handle and turns easily when compared to take a turn in cruisers.
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| Yamaha R15 |
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| Royal Enfield - Classic 350 |
Now I hope everyone may have some basic idea about cornering. Now we shall see what makes this difference of cornering between these two bikes and what are the natural forces that act on a bike during cornering.
Centre of Gravity
It is a point where the entire weight of the bike is concentrated and fall at a particular point. For better handling the centre of gravity should be low as possible. Low centre of gravity means that it should have few points where the entire bike's weight is centralised and balanced. High centre of gravity means that the weight of bike is distributed at differnt points and not centralised properly.
It is a point where the entire weight of the bike is concentrated and fall at a particular point. For better handling the centre of gravity should be low as possible. Low centre of gravity means that it should have few points where the entire bike's weight is centralised and balanced. High centre of gravity means that the weight of bike is distributed at differnt points and not centralised properly.
While designing a chassis it can be clearly seen that the engine placement, seating position and fuel tank placement is made in such a way that it focuses towards centre so the entire weight is concentrated over there. Sports bikes have a chassis like V pattern to minimise the centre of gravity.
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| The Delta Box Chassis Used In Yamaha R15 |
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| Royal Enfield Classic 350's Chassis |
The cruiser bikes have higher centre of gravity this makes cornering little difficult when compared to sports bikes, but they are well suited for long rides. So a bike with higher centre of gravity has to lean less while making a turn.
Camber Thrust
A leaning tyre when rolled will describe an arc. But when attached to a cornering bike, is is not able to follow the natural arc and thus creates a force called the camber thrust. It is the direction which the tyre wants to travel.
Centrifugal force
Rational inertia acting outwards, away from the turn. In case of bikes when we go around a bend, a force is generated which tends to push you out of the turn. This force also helps to keep the bike from falling down into the turn.
Centripetal Force
It is an equal and opposite force to the centrifugal force. It is required to hold the bike in a circular motion. This force is created by the camber thrust of the tyres.
Feedback
The feedback can be anything that a rider feels from his bike when out riding it. This feedback is essential to know how the bike is behaving in turns, the state of road and levels of grip. Many bikers don't know how to interpret these feedbacks and what it represents. Based on the feedbacks the bike's performance can be judged and improved.
Geometry
Based on the better geometry behind the motorcycle the performance of the bike can be drastically improved. These are the factors essential for better handling, cornering and stability behind the motorcycles.
-Centre Of Gravity
The point around where the entire mass of the bike is centralised and balanced. This point plays a vital role in handling and braking.
-Rake
Rake is the angle between the steering axis and a vertical line. It is basically the steepness of the forks. Rake angle is also called as castor angle and plays an important role in the handling characteristics of the bike. A steep rake will give the bike a sharper handling but the stability becomes low (used in sports bikes) whereas a shallow rake (used in cruisers) will enable slow handling but provides better stability.
-Trail
Trail is the distance between the centre of the contact patch of the front tyre and the point where the steering axis hits the ground. When the steering is deflected, it's the trail which brings the front wheel back into line. In sports bikes, the trail will be less so it is less stable but it is easier to turn the bike as compared to cruisers. In cruisers the trail will be longer making it more stable but slower to turn.
-Wheelbase
Wheelbase is the horizontal distance between the front and rear wheel. Longer the wheelbase, more stable the bike will be. Whereas the shorter the wheelbase, more flickable the bike becomes. This suits also to cars.
-Offset
If you draw an imaginary line down the centre of the forks and second line along the centre of the steering axis, the perpendicular distance you get between the two lines is known as fork offset. This is used with rake angle to determine trail.
All these factors are considered while designing a bike which makes it ultimate one both in handling and performance.
