[bmxmon]

if its like the back ones, there is a little hole in the back of the brake, which you can stick a screwdriver into, and in there is this little wheel, which you turn with the screwdriver and it loosens the drum. You should be able to see the wheel, its perpendicular to the brake plate (the thing with the hole) and it has all kinds of little ridges on it to move it with your screwdriver. Hope this helps.