Hello Denise, first lets be sure we´re talking about a KZ750M1 or CSR. Assuming we are: I checked the hose I think you mean. Indeed ther´s a ´seethrough´ going from one of the 3-way joints that is in the middle of the two carburettors. It´s just hanging there and ends up somewhere on the left side of the bike. Probably its for getting rid of to much gasoline at some time... I´m not sure. If you need more info I can take a picture if like. Regards, John PS: My bike had problems with getting the ignition timing right, now for some reason the engine won´t throttle down...