How to Adjust a Carburetor on a Honda 360 Motorcycle

by William Machin
Adjust the carburetors on a Honda 360 motorcycle with the engine running.

Adjust the carburetors on a Honda 360 motorcycle with the engine running.

The Honda 360 motorcycle has twin cylinders with overhead valves and dual carburetors. Produced between 1974 and 1976, the CB360 was Honda's answer to demands for a middleweight road bike with more power than its predecessor CB350. Honda stayed with the single throttle-lever Keihin carburetors on the CB360. Raising the rider's seat gives you access to the throttle-stop adjustment between the units. The pilot-air mixture adjustment screws are located on the outside of each carburetor. You adjust the carburetors on a Honda 360 motorcycle using metric tools. It helps to have an assistant.

Flip the catch on the rider's seat and raise the seat. Prop the seat in the raised position with a wood dowel or ask an assistant to hold the seat while you adjust the throttle stop.

Twist the throttle handgrip a few times as you look between the dual carburetors. Notice the throttle lever rotate as the hand grip is twisted and released. Locate the throttle-stop screw at the lower end of the throttle lever.

Set up a metric socket and ratchet with an extension. Push the socket onto the throttle stop screw and turn the screw slowly clockwise as you watch the tachometer gauge. Turn the throttle stop screw until the tachometer reads 1,300 rpm.

Locate the brass pilot-air screw on the outside face of the right carburetor. The screw has a slotted head with a tension spring on the stem of the screw.

Turn the pilot-air screw slowly counterclockwise with a screwdriver until you hear the engine idle speed begin to drop. Turn the pilot-air screw slowly clockwise until the engine speed picks up and drops again. Turn the screw counterclockwise again and find the point where the engine idle speed is at the highest.

Adjust the pilot-air screw on the left carburetor in the same way. Turn the pilot-air screw each way with the screwdriver and find the point where the engine idle speed is at the highest.

Push the socket on the throttle-stop screw between the carburetors. Watch the tachometer gauge as you turn the stop screw slowly counterclockwise until the tachometer reads 1,100 rpm. Lower the rider's seat.

Twist the throttle handgrip several times in short, quick bursts. If you notice a delay in the throttle response, turn the throttle cable adjuster at the handgrip clockwise a quarter-turn with a metric open-end wrench.

Twist the throttle a few more times in quick bursts. Adjust the throttle cable until the throttle response is immediate.

Items you will need

  • Dowel (optional)
  • Metric socket and ratchet
  • Socket extension
  • Standard screwdriver
  • Metric open-end wrench

About the Author

William Machin began work in construction at the age of 15, while still in high school. In 35 years, he's gained expertise in all phases of residential construction, retrofit and remodeling. His hobbies include horses, motorcycles, road racing and sport fishing. He studied architecture at Taft Junior College.

Photo Credits

  • Jupiterimages/ Images