Seeing that tractor sent a shiver down my spine - wrote my first bike off on the side of a tractor - he just didn't see me. (apparently that's what he told the off duty policeman who was following me at the time). I was 18 and only been on the road for about 3 months so a bit green. Luckily hit the front wheel and got thrown onto the verge the other side of the road. No serious injuries but a lesson I never forgot.