Alignment of wheels is very important, and in our previous articles, we have discussed various factors affecting the alignments of wheels such as positive and negative chamber settings and also about the positive and negative toe. Apart from these factors, the castor angle is also an important part of wheel alignment.
The castor angle is basically used to define how much the mounting point of the strut is in relation to the forward and backward of a tire. Since the castor angle is not easy to understand; hence, you need to look at the figure below to understand the castor angle properly.
As you can see that compared to the vertical axis, how the tire is placed forward. So, it will be a positive axis when the tire moves forward, and it’ll be a negative castor when the tire is being pushed behind the verticle axis.
In order to understand the castor angle in the best way, let’s take the example of the wheels of shopping trolleys. Positive castor is created when wheels of trolly are folded backward when you push it. Doing this makes it easier for you to push the trolley, and you can easily turn and take away the shopping trolley wherever you want to. Now, the negative castor angle would be created when you try to turn the tires of the trolley at 180 degrees. Doing this would not only make the trolley hard to steer, but it’ll also be very unpredictable, and you might run into an accident by hitting a fellow shopper and thus creating an unnecessary commotion.
For normal cars, usually, the castor angle is kept positive in regard to wheel alignment because not only it is needed to give a straight line ability to the cars but is also very important in regard to giving the car an ability of directional steering.