Help please.. a basic problem if you're a pro

It seems the problem I'm having is that the whole brake calliper mounting-bar thing (sorry dont know the terminology) is twisting so that the brakes are mainly applying from one side, if you see what I mean. I line it up perfect, apply the brakes a couple of times and leans to one side straight away, but the necessary bolt is done up right tight!

any tips? are my callipers f*cked? is it something to do with the little mud guards that are attached via the same bolt thing?

Thanks

Nick

You need to centre the brakes, just tightening the retaining bolt haphazardly will generally not acheive this.

Please read Sheldon Browns brake adjustment pages

http://sheldonbrown.com/brakes/index.html