This is the only way that I can manage to do this and 2 people are needed. Up-end the dyson and remove the sole plate by 1/4 turning the 3 plastic screws using a coin, they give a slight click when they are disengaged. Remove the sole plate and the brush bar. Clean the spindle at the rear and loop the new belt round it. Thread the belt through the cut-out. Through the new belt pass a thick rope with enough spare to wind round your hand. One person needs to hold the dyson while the other pulls the belt through the cut-out and far enough for the brush-bar to pass through. Slip the belt over the rounded groove in the brush bar and replace checking that the end caps are correctly aligned. Replace the sole plate.
Pauline
November 2014