Just to add to this ,I have spoken to a few riders who have had very rapid deflation of their tyres (blow out) because the valve has "Delaminated" that is where the valve is fitted onto the tube it has simply came off resulting in the tyre going down in a split second .they were using VEE RUBBER inner tubes cheap as **** made in taiwan ,just be carefull I bought heavy duty inner tubes . If your fitting new tyres check out the make of inner tube .