It has got something to do with the bite of the disk brake being applied only of the right ride. This causes a uneven distribution of braking force. It is what I have observed. If the bike is straight and you manage to lock the wheel, it will fall to the right.

It doesn't work like this, actually. If you are experiencing this in your bike then either there's some alignment problem or a rider fault. The front disc set up at either right or left side of the tyre is hardly an issue in this situation, it's just in manufacturer's prerogative whether they want to put the disc at right or left side of front tyre. However, if the disc is slightly bent which is not noticeable to the naked eye, then there might be stability problems under braking, but even then it doesn't guarantee that the bike will fall on the right side only!!! that could only be a mere coincidence!

Its not a stability problem as such. When you skid for some time under hard braking, you are bound to fall. Here, I have observed that the fall is mostly to the right. And this thing is not only in my bike. Anyways, will try to find some info from the net.