It is normal for the cop bike to have no drain hoses because the float bowls work differntly than your Teikei carbs. On the Mikuni VM and Teikei round slide, there are tubes running up the middle of the bowl which allow overflow the drain. The Mikuni BS34 doesn't have this tube. If it overflows, it comes up out the needle jet in the main venturi area (into airbox and combustion chamber). The drain on the BS34 bowl has a drain nipple which can be opened by unscrewing a drain screw on the side. As you loosen, the screw moves back and allows gas out the nipple. Since overflows are a tad serious on the BS34, the float needle seat (brass thing screwed into carb where float needle seats) has a screen attached to the bottom to keep debris from entering the needle/seat contact area and allowing the needle to keep from shutting and thus overflowing. It is very important to keep this screen clean and use a gas filter on a bike using BS34 carbs.