A cyclist in circular motion (e.g round the running track) has acceleration towards the centre of the circle (i.e along the floor). You cant see it because it is provided by friction. However if he cycle too fast , and friction needs to be increased , he got to slant himself and bicycle (push outwards to get a reaction inwards) to satisfy this large force required.
Centripetal force F=mv2/r needs to be provided by real forces like friction.The factors affecting the force is mass and speed and radius. There is no factor for direction as it is always towards the centre of the circle.
