Understeer explained.

This video explains about understeer "how it happens and how it can be avoided".Mechanical Engineering tutorials videos 

While taking a turn when the tyre looses the traction or grip, it can result in understeer or oversteer.
How understeer happens:

Automobile Engineering tutorials When a vehicle is taking a turn, it normally moves towards the apex. The front wheel is turned to take the turn, but the vehicle moves away from the desired path and moves off the road. The vehicle or car goes out of the road or track as the turn is not achieved due to under steer. The video animation clearly shows how understeer occurs.
How to avoid under steer:
Understeer can be avoided by using soft rear tyres, by reducing the rear tyre pressure, softening rear spring etc.

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