Lust leaving Lyme Regis this morning to go out for lunch, the 40 zone had just ended but I kept at 40mph. ½ mile further on a I confronted with a lady jogger running towards me, 5 motor cycles coming towards me in the center of their lane,,, so I thought ok just ease off on the throttle and all will be fine. Just passing the lady and I hear this dull thud sound, and in my nearside mirror there is the lady lying in the ditch. Strange I though the nearside mirror is fine so I stopped and got out, and there was this Fiesta that had been behind me smashed into a tree. I knew that there was a white Fiesta behind me but concentrating on the lady jogging I was not looking in the rear mirror. It was the Fiesta that knocked her over, the girl driving said that her brakes were poor and she did not want to hit me up the rear. The jogger was not hurt, just a bit shaken and muddy. I gave her my phone number and we went on our way. The Police were not called and they did not want to know about the Fiesta with poor brakes. The accident had not been reported.