yea only ever managed to lock them up when going down a hill, turned a small s bend and doing no more than 30mph there was a bus near the bottom of the hill pulling into a car park so i started to slow down when they locked on and ended up sliding sideway down with my front end nearly dragging on a wall, and while trying to correct ended up facing the other direction stopped..........
luckily i didnt do any damage and was nowhere near the bus lol