Tires have been taking an important role in vehicle safety in the last years. A lot of efforts have been taken in the way that we can understand, predict and follow its behavior, in the way that this could be useful for vehicle safety increasing. In this direction, several models describe the tire interaction with ground, considering the steering angle, pressure, temperature, friction coefficient and thread as well. Inside this analysis, there is the tire slip angle value, that is consequence of lateral forces acting over the tire. This characteristic is predicted in some cases, and evaluated on another ones. This paper brings to community another point of view of slip angle. We propose a mathematical model that describes a constraint linking slip angles and steering angle, in the way that makes the vehicle turns. We present the kinematic model that makes all three angles compatibles each other, function of the radius' corner. This model was simulated under two different scenarios, for an udersteering and an oversteering vehicles. At the end we show the results and the conclusions that we reached.