The document discusses wheel alignment and balancing. It defines wheel alignment as ensuring the wheels are perpendicular to the road surface and parallel to each other for straight and safe driving. Key alignment measurements like camber, caster, and toe are explained. Wheel balancing ensures the wheel and tire assembly spins smoothly at high speeds by equalizing weight distribution to minimize vibration. The benefits of proper alignment and balancing are outlined as reduced tire wear, improved safety and handling, and less stress on vehicle components. Dangers of unbalanced or misaligned wheels such as premature tire wear and vehicle pull are also noted.

1. WHEEL ALIGNMENT
AND BALANCING…..
Prepared by : Engr. Md. Imam Hossain Rubel
E-mail: rubelduet04@gmail.com
Cell Phone: +8801818261989
12/13/2015

2. Yes
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

3. 12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

4. The alignment is concerned with the wheels being perpendicular
to the surface of the road and that the wheels are parallel to
each other. This means that the car will drive evenly. It allows the
vehicle to go down the road as straight as an arrow with no one
side being overly stressed. Proper alignment can also allow for
quicker stops and a shorter distance to cause that stop.
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

5. 12/13/2015

6. Camber
Caster
Toe
Steering Axis Inclination
Turning Radius
Thrust Line
Scrub Radius
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Mohammad Imam Hossain Rubel,
Skype:mdimam

7. Camber: Camber is the angle of the wheel, measured in degrees, when viewed from
the front of the vehicle. If the top of the wheel is leaning out from the center of the car, then the
camber is positive, if it's leaning in, then the camber is negative. If the camber is out of
adjustment, it will cause tire wear on one side of the tire's tread. If the camber is too far
negative, for instance, then the tire will wear on the inside of the tread.
.
.
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

8. Caster: When you turn the steering wheel, the front wheels respond by turning on a
pivot attached to the suspension system. Caster is the angle of this steering pivot, measured in
degrees, when viewed from the side of the vehicle. If the top of the pivot is leaning toward the
rear of the car, then the caster is positive, if it is leaning toward the front, it is negative. If the
caster is out of adjustment, it can cause problems in straight line tracking. If the caster is
different from side to side, the vehicle will pull to the side with the less positive caster. If the
caster is equal but too negative, the steering will be light and the vehicle will wander and be
difficult to keep in a straight line. If the caster is equal but too positive, the steering will be heavy
and the steering wheel may kick when you hit a bump. Caster has little affected on tire wear.
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

9. Toes :The toe measurement is the difference in the distance between the front of the tires
and the back of the tires. It is measured in fractions of an inch in the US and is usually set close
to zero which means that the wheels are parallel with each other. Toe-in means that the fronts
of the tires are closer to each other than the rears. Toe-out is just the opposite. An incorrect toe-
in will cause rapid tire wear to both tires equally. This type of tire wear is called a saw-tooth
wear pattern as shown in this illustration.
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

10. Steering axis inclination or kingpin (KPI) : The
steering axis inclination is the tangential deviation of the pivot
axis with respect to a vertical line to the roadway (seen from the
vehicle steering axis).Steering axis inclination and camber
together form an angle that remains the same upon deflecting in
and out.
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

11. Toe out on Turn or Turning Radius : When you steer a
car through a turn, the outside front wheel has to navigate a wider arc then
the inside wheel. For this reason, the inside front wheel must steer at a
sharper angle than the outside wheel.
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

12. Thrust Angle : The angle between the vehicle’s centerline and the
vehicle thrust line. When driving, the front wheels and the rear wheels should
pull to the same side if the thrust angle is not zero. When thrust line is at the
left side of the vehicle’s centerline, the thrust angle is positive, otherwise is
negative
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

13. Scrub Radius: Scrub radius is the distance between where the SAI
intersects the ground and the center of the tire. This distance must be exactly
the same from side to side or the vehicle will pull strongly at all speeds. While
included angle problems will affect the scrub radius, it is not the only thing
that will affect it.
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

14. Included Angle: Included angle is the angle formed between the SAI and the
camber. Included angle is not directly measurable. To determine the included angle, you add the
SAI to the camber. If the camber is negative, then the included angle will be less than the SAI, if
the camber is positive, it will be greater. The included angle must be the same from side to side
even if the camber is different. If it is not the same, then something is bent, most likely the
steering knuckle.
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

15. Reduce wear on tires
Better gas mileage, due to less work on the engine
Smoother driving, lack of vibration at high speeds
Straighter driving with no pulling to one side or the other
Improved safety
Shorter stopping distance
Safer Driving
Save Money & Environment
Improve fuel consumption, brake & Steering condition
 Maximum tire life and a vehicle that tracks straight and true
when driving along a straight and level road.
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

16. The symptoms and dangers of a car that is out of alignment are:
Wheels that are not aligned will compromise your safety and the ability to steer the
vehicle.
Out-of-alignment of a car will result in the vehicle continuously drifting or pulling to
one side of the road when you let go of the wheel.
If the wheels aren’t going in a straight line it means the tyres will be dragging sideways
to some extent - Pulling or drifting away from a straight line.
This is not only annoying, but the tire that is out of alignment will also wear
prematurely and unevenly because of the constant drag placed on its tread.
As the tread wears away the ability for the tyre to grip wears away with equal rapidity.
The drag can also impact on fuel consumption.
Braking, handling, the ability to react to steering input or any form of evasive action
becomes compromised.
This is especially important when the driver has to respond swiftly and change course
in an emergency situation
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

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Mohammad Imam Hossain Rubel,
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18. Wheel balancing, also known as tire balancing, is the process
of equalizing the weight of the combined tire and wheel
assembly so that it spins smoothly at high speed. Balancing
involves putting the wheel or tire assembly on a balancer,
which centers the wheel and spins it to determine where the
weights should go.
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

19. Vibration in the steering wheel at certain highway speeds.
Vibration in the seat or floorboard at certain highway
speeds.
Scalloped or cupped wear pattern on the tires
Note: Scalloped one of a continuous series of circle
segments or angular projections forming a border (as on
cloth or metal or rubber)
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

20. When the tire rotates, asymmetric masses cause the wheel to wobble,
which can cause ride disturbances, usually vertical and lateral vibrations.
It can also result in a wobbling of the steering.
Wheels that are not balanced or are out of balance generally produce a
vibration that is uncomfortable to drive in and results in premature
wearing of suspension and steering components, rotating parts and
tyres.
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

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22. Static balance: The condition which exists in a body which has an absolutely even
distribution of the weight mass around the axis of rotation.
This occurs when there is no resultant centrifugal force and the center of gravity is on
the axis of rotation.
Dynamic balance: The condition which exists in a rotating body when the axis about
which it is forced to rotate, or to which reference is made, is parallel with a principal
axis of inertia; no products of inertia about the center of gravity of the body exist in
relation to the selected rotational axis.
Occurs when there is unequal weight on one or both sides of the wheel assembly's
lateral centre line, creating a side-to-side wobble or wheel shimmy. The dynamic
imbalance creates a side-to-side or wobbling vibration. This occurs when there is no
resulting moment along the axis.
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

23. Static imbalance: Dynamic imbalance:
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Mohammad Imam Hossain Rubel,
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24.  The tire is made free from all the small stones, if any .
The wheel is fixed to spindle of wheel balancing machine by use of quick cone lock
nut.
Quick cone lock nut ensures fast mounting and fast removal of tire.
Wheel balancing machine is switch on.
The spindle is made to rotate at speed of 400 rpm.
The rotation of the spindle is stopped.
 Wheel balancing machine determines the size of weights and where to locate
weight on the wheel.
The size of the weight and location of the weight to be placed is shown on the
monitor of the wheel balancing machine.
The weight is fixed to rim at exact location which is shown on the monitor.
And wheel is removed from the spindle of wheel balancing by the use of quick cone
lock nut.
Now the wheel is balanced.
Now it can be used for comfortable driving.
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

25. Weight on rimWeights (Zinc)
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26. Consider a light arm pivoted freely at the fulcrum O and carrying masses m1,
m2 at distances r1, r2 from O respectively. In general the arm will rotate about O
and the system is said to be out of balance. For equilibrium there must be
balance of moments about O. i.e.
m1g x r1 = m2g x r2
or
m1r1 = m2r2
When in balance the arm may be set in any position and will remain at rest in
that position. The weights are said to be in static balance and the center of
gravity of the system is located at O.
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

27. Now consider two light arms fixed to a shaft at bearing O and rotating with
angular velocity ω. The arms are in the same plane and carry masses m1, m2 at
radii r1, r2 respectively. Owing to the rotation each masses exerts an inertia
force radically outward on the bearing O.
The force due to m1 is m1 ω2 r1 (OA in the force diagram)
The force due to m2 is m2 ω2 r2 (AB in the force diagram)
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

28. The resultant out of balance force on the bearing is given by OB in the force diagram.
when the dynamic load on the bearing is zero the rotating system is said to be in
dynamic balance. The condition for no load at O is that two inertia force shall:
1. act along the same straight line but with opposite sense
2. Be equal in magnitude
the relative positions of the masses are as in the figure C shown earlier. The
condition for equal inertia forces is:
m1 ω2 r1 = m2 ω2 r2
Thus, since ω2 is the same both masses
m1r1 = m2r2
Two bodies in the same plane are in static balance when pivoted about a given axis
they will be in dynamic balance at any speed when rotating about the same axis
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

29.  Wheel balancing will ensure a smoother ride and more enjoyable driving.
 The tires and wheels to spin without causing any vibrations.
The better wear from the tyres will save you time and money.
 Vibration free that is comfortable to drive in and easy to handling of the vehicle.
 Remove stresses and strains on the wheel bearings and suspension components.
 Steering components can be safe and prevent from failure of prematurely extreme cases
to all the parts.
 Protect from premature wearing of suspension and steering components, rotating parts
and tyres.
 Decrease the need for additional energy and reduce fuel consumption.
 Save from any dangerous and expensive accident.
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

30. We would like to reflect on the dangers of driving with unbalanced wheels:
Wheels that are not balanced or are out of balance generally produce a vibration that
is uncomfortable to drive in and negatively affects the handling of the vehicle.
Unbalanced wheels place severe stresses and strains on the wheel bearings and
suspension components.
Steering components can also be damaged and all the parts may fail prematurely in
extreme cases.
Unbalanced wheels result in premature wearing of suspension and steering
components, rotating parts and tyres.
Unbalanced wheels increase the need for additional energy and increase fuel
consumption.
Ignoring the symptoms can be dangerous and expensive.
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam

31. Road Safety authorities have given much attention to vehicle maintenance
and aspects such as tyre safety. Vehicle factors are contributing factors to
road crashes and we would like to advise vehicle owners and drivers to
pay close attention to their vehicles and vehicle components. This will
allow them the best possible chance to arrive safely at their destination!
Aspects often neglected by vehicle owners are wheel balancing and wheel
alignment. Most often these aspects are confused and little attention is
given to their importance. They contribute towards tyre life, and are both
important for your safety on the road!
12/13/2015
Mohammad Imam Hossain Rubel,
Skype:mdimam