Another option is using auto hose with a 12 mm or 1/2” ID as this will fit the 750 K. Usually found under fuel, emission, heater and transmission hose. Much thicker OD due to the reinforced construction than the OEM hose/tube and it will work just fine. The 750 K6 re-routed the breather tube away from the rear tire, which some earlier K owners can take advantage of.