Each high quality air cutoff valve kit for the '75-'79 GL1000 that has the parts necessary for a complete rebuild i.e. diaphragm, spring and O-ring. Replacing your air cutoff valve will improve starting, warm up, idling and acceleration. Read FAQ4. To further insure against any additional vacuum loss, replace your inexpensive carburetor manifold o-rings, 18-4610. Note: The GL1000 and GL1200 require one air cutoff valve but the GL1100 requires four. This price is for a single kit. Click for Installation.