The Suevia engine has a fairly unique carb design that I hadn't seen before. The brass needle holder on the one end of the carb body has a expensive set of helical cut worm gear teeth on it. The steel throttle barrel has a matching set of helical cut worm gear teeth. When you mate the two together the barrel moves in and out as it rotates. There is no slot for a stop screw, without a throttle pushrod on the throttle, the barrel assembly can unscrew itself and fall out. Other than that it is a two needle carb design. I don't know who designed such a carb like that though.