How often you should balance tires
Administrator World Garage
Many drivers neglect such operation as balancing of wheels. To dispel all doubts about need for its implementation, we will consider in this article what wheel balancing is, why it is needed and how often it is necessary to do it.
Wheel balancing is process of reducing unbalanced wheel rotation to an acceptable level. That is, in simple terms — elimination of beating of wheel during rotation caused by centrifugal force.
The main types of imbalance and wheel balancing
The first type is static. This imbalance is that axis of rotation and axis of inertia are parallel to each other, i.e. there is longitudinal beating of wheel. In this case, center of gravity of wheel is shifted from axis of rotation, with total weight of wheel is distributed along its length unevenly.
To see such an imbalance is not difficult-it is enough to untwist disc with tire (not even much) on rotating axis and see what will be rotation of wheel.
If there is static imbalance, rotation of wheel will be "jumping" relative to axis of rotation, i.e. vertically and wheel itself will stop quickly.
The second type is dynamic. It appears when axis of inertia does not coincide with axis of rotation. In this case, center of gravity of wheel does not shift from axis of rotation, i.e. is on it, but axis of rotation intersects with axis of inertia at some angle. Otherwise, it can be explained as follows: weight of wheel in this case is incorrectly distributed across width, and not along its length, as in static imbalance.
Naturally, dynamic imbalance is more often present on tires with wide profile.
There are cases that wheel may be both types of imbalance at same time. But they are easily eliminated when balancing on balancing machines of any kind and type, regardless of manufacturer of equipment. quality of balancing depends more on qualification of specialist performing balancing, and condition of machine itself, i.e. machine must be regularly maintained, maintained, calibrated and verified. If these conditions are not met even most expensive machine will not show correct results. Both these imbalances are eliminated with help of special balancing weights installed in certain places with help of balancing machine.
At increased requirements to balancing of wheels (e.g., race cars) running finish balancing. It is produced as follows: car is suspended on special stand and in this state wheel is spun to speed of 90 kilometers per hour. computer makes necessary measurements and indicates place where it is necessary to install appropriate weight. However, this type of balancing is not an alternative to stationary balancing — balancing on stationary stands. finish balancing stand is designed only for static balancing, and entire hub Assembly, i.e. hub together with brake disc and wheel. When using such balancing, maximum permissible weight of balancing weight, designed to correct imbalance of node, can not exceed 15 grams. It is also necessary to take into account that before final balancing wheel must be necessarily balanced on stationary stand.
Such equipment is very rarely present on tire sites. For normal operation of vehicles, balancing on conventional equipment is sufficient.
There is another type of balancing — automatic balancing. It is usually used when balancing on large wheels of buses and trucks. It is performed as follows:
Inside wheel are filled with special granules. During movement, they stick to inside of tire in right places. Thus, there is an automatic balancing.
Few of car owners will be able to clearly answer this question. main reasons for this operation are requirements of traffic safety, extension of life of suspension elements, comfort when driving and so on.
Every car owner should understand that unbalanced wheels lead to appearance of centrifugal forces, which should not be. These forces are transmitted from wheels to suspension elements and then directly to body itself. They operate in different directions, and therefore when car appears increased vibration and excessive load on car as whole. And almost none of drivers do not think that impact force on suspension is strong enough - imbalance of 14-inch wheel is only 20 grams at speed of 100 km/h, resulting loads are equal to blows of sledgehammer weighing 3 kg, which hits wheel with frequency of 800 times per minute!
The decision on whether to balance wheels or not every car owner takes on their own, and no one has right to force him to do it. But we must remember saying - "miser pays twice." Indeed, if you do not balance wheels, results can be disappointing and costly. Here are some examples of what can be result when using unbalanced wheels.Increased wear of tire, and as consequence of this reduction in its service life. Due to constant vibration of wheel tire contact with surface of road is not constant, and therefore there is effect of "slipping" tires. It turns out that due to constant "slippage" tire protector is quickly erased. Therefore, tire will have to be replaced much earlier. And this is an additional cost.
- Traffic safety is reduced. I will explain what it is. It is almost impossible that centrifugal forces of all four wheels act in same direction at same time. Imagine how car will behave if right front wheel is itself on flat road to jump up and down left... And add rear wheels to that. And now take into account fact that centrifugal forces are not only up and down, and all 360 degrees of rotation of wheel, and that they are present on all four wheels in completely different directions. And keep in mind that when driving on these wheels these centrifugal forces with every meter change their direction primarily because of presence of "slippage effect", with each wheel on your angle of displacement. What do you think will happen to car? Quite right, it will be difficult to control, its movement in certain situations can be unpredictable. With the" effect of slippage " reduces effectiveness of brakes-the braking distance of car increases significantly. consequences of this can be catastrophic — loss of control and accident. Surely there is someone who will object to me and say: "And I've been riding on unbalanced wheels for so many years and nothing..."It's just that he was very lucky that he never got into situation where score goes to milliseconds and millimeters. And let none of you ever get into such situations. But, unfortunately, none of us is immune from them. car is device of increased danger, and whether You need this danger still improve?
- Suspension units are subject to increased wear. Due to constant vibration impact on bearing units of suspension is their rapid wear. In first place, as rule, there is wear of hub bearings, which in certain situations can collapse completely.
- Unbalanced front wheels transmit vibration to steering wheel. This vibration causes discomfort when driving and, as consequence, increased fatigue of driver.
- I think these reasons are more than enough for timely implementation of wheel balancing.
Do I need to balance rear wheels?Among car owners there is perception that rear wheels do not need to balance. Their arguments are that vibration is not transmitted to steering wheel, there is no feeling of uncomfortable driving. But this opinion is fundamentally wrong. It is necessary to balance both front and rear wheels. If driver does not feel obvious discomfort from unbalanced rear wheels, it does not mean that car does not have problems described above. Indeed, if only rear wheels are unbalanced, there will be less vibration, but this does not mean that there will be increased wear of car parts. And prematurely will fail not only rear suspension parts, but also front, as well as all four wheels. Let us imagine what will happen to front wheels when driving, if back wheel will be blow in opposite direction to movement of car? That's right — there will be slip of front wheel, and, accordingly, this blow will be transmitted from front wheel to front suspension elements. But if such attacks occur constantly with frequency of 800 beats per minute?.. I think then it makes no sense that something else to describe — so everything is clear. So I suggest that those who balance only front wheels think again and appreciate everything.
Do you often do balancing?Often, especially beginners, question arises — how often should I balance wheels? In regulatory literature there is no clear requirement for wheel balancing by time or mileage. But from our experience we can offer you some recommendations.Balancing is desirable to carry out:
- When installed on drive tires, whether new or used.
- Approximately every 5000 kilometers of car.
- After hitting car in big hole or after breakdown of car suspension.
- When vibration of car body and/or beating in steering wheel when driving, most often at speed of more than 60 km / h.
- Every time wheel is repaired.