well, with my bike racing, i have actually thought about it, thanks to that top gear show, and i figured out that, at least part of it, is that i have total faith in my vehicle. the tyres will stick, i will get the lean angle, the brakes will work etc... im not thinking...what if the rear slides, what if the brakes lock, nothing like that
i think thats part of it, as well as pure confidence in your own ability.
alot of racers, car and bike, that ive met are confident in their own lifes, some to a cocky stage.