Front wheel toe-in means that the distance between the front ends of the two front wheels of the car is smaller than the distance between the rear ends. The difference in distance is called the toe value. Looking down from the top of the car, the left and right front wheels form a figure-eight shape with the opening facing backward.
Contents
Basic introduction, detailed introduction of basic functions
Edit this paragraph Basic introduction
The toes point inward, the so-called "splayed feet" means that the left and right front wheels are facing inward respectively. The purpose of adopting this structure is to correct the outward rotation of the wheel caused by the above-mentioned front wheel camber angle. As mentioned earlier, steering wheel operation is made easy due to the camber. On the other hand, due to the tilt of the wheels, the left and right front wheels rotate outward respectively. In order to correct this problem, if the left and right wheels have an inward angle, the plus and minus are zero, and the left and right wheels can keep traveling in a straight line, reducing tire wear. Edit this paragraph Basic functions ① The front wheel camber has a tendency to turn the front wheel outward, and the front wheel toe has a tendency to turn the wheel inward, which can offset the adverse effects caused by the front wheel camber and make the wheel roll in a straight line. There is no lateral slippage, reducing tire wear.
② The deformation of the hinge points of the suspension system also causes the front wheels to tend to turn outward, which must also be compensated by the toe-in of the front wheels. The front wheel toe value is generally not greater than 8mm, and its value is guaranteed by adjusting the length of the tie rod. The toe-in value of modern cars has a tendency to shrink. When the front wheel camber is negative, the toe-in is also negative, that is, it becomes the front wheel toe-in. Edit this paragraph for details: In order to ensure the stable straight-line driving of the car, the steering wheel should have an automatic back-aligning function, that is, when the steering wheel accidentally encounters an external force (such as hitting a stone) and deflects, it can immediately return to normal after the external force disappears. Automatically returns to the straight-line driving position. This righting effect is ensured by the positioning parameters of the steering wheel. Front wheel toe is one of these positioning parameters.
In order to eliminate the adverse consequences of wheel camber, when installing the wheels, make the center planes of the two front wheels of the car non-parallel. The distance between the front edges of the two wheels is smaller than the distance between the rear edges. The difference between the two distances That is the toe-in of the front wheel.
In order to maintain the appropriate front wheel toe value, the four wheels need to be positioned regularly. However, since the measurement and adjustment of the front wheel toe are relatively simple, as long as you are willing to do it, there is no need for a dedicated four wheel toe. The locator can complete the measurement and adjustment of the front wheel toe.
Before the formal measurement of toe-in, you should first ensure that the front wheel hub bearing is properly tightened and the front wheel tire pressure is normal. Then park the car on a flat site so that the two front wheels are in a straight line. position, and push it forward 1 to 2 meters to eliminate gaps that affect the inspection effect. Then support the two ends of the front toe scale horizontally at the minimum distance on the inside of the two front tires, that is, the highest point of the sidewall. Its height should be the same as the horizontal centerline of the front wheel. Then put the front toe gauge in place and move the scale so that the pointer is aligned with the "0" position, and then push the car forward until the front toe gauge is rotated until the back is at the same height as the center line of the wheel. At this time, the pointer on the scale is pointing. The numerical value is the measured toe value.
Adjustment of toe-in
The toe-in of the front wheel can be adjusted by changing the length of the tie rod. When adjusting, the measurement position specified by the automobile manufacturer can be used to make the front-to-rear distance difference between the two wheels meet the specified toe-in value. Generally, the toe-in value is between 0 and 12 mm.
If the car tie rod is straight, you can first loosen the locking bolts of the joints at both ends of the tie rod, and use a pipe wrench to twist the tie rod to extend or shorten the tie rod. When the tie rod is extended, the toe value increases; when the tie rod is shortened, the toe value decreases. Tighten the bolts until the front toe meets the standard.
If the car tie rod is bent, the tie rod cannot be rotated during adjustment, but the pullers at both ends of the tie rod should be rotated. And because the thread pitches at the left and right ends are different, when adjusting, you should first rotate the tie rod joint on one side. If the toe-in value is exceeded after one rotation, and if the toe value is exceeded after one rotation, and the toe value is not met after one rotation, you can rotate the tie rod joint on the other side again. Adjust the tie rod joint until it meets the requirements. After adjustment, tighten the locking bolt.