Fastest i drove was 175 km/h on a totally empty brand new tarmac highway with no cars in site in a Golf MKII 1.8, 90 hp...
I don't think i'll ever go that fast again considering the condition that my car is and his age, especially that those 175 felt like going 250..
My speed varies to the speed of the car ahead of me... When going to work (daylight) i ride in the midlle lane at about average 80-100 km/h simply because car ahead of me doesn't go any faster so i try to maintain his speed and distance beatween us, and i don't fancy getting early to work..
(it's highway btw)
At night(or better say, early in the morning), at the same highway i go about 100, 120... depends on my mood...
I simply don't want to go faster because i don't have any of the modern safety gadgets in the car, my suspension is pretty low and stiff and is just uncofortable going faster than that...