Fuel System

OEM Japanese Fuel Hose

Honda seems to use the "red stripe" fuel line. This can be found at Sudco's site. They claim it's made by Kitaco (Kitako seems more likely) in Japan. It's available in 3.5mm, 5.5mm, 7.5mm, and 8.0mm inside diameters.

Sizing

Sizes are generally given in terms of:

• Inside Diameter (I.D.)
• Outside Diameter (O.D.)
• National Pipe Thread (NPT)

Tank Outlet

Most Hondas I've seen use 3/8" NPT outlets on their tanks. Some bikes use custom adapter plates. Later Honda CB750's use what appear to be Harley-Davidson style 22mm outlets.

Fuel Hose

Honda fuel line seems to always be 8mm inside diameter (just over 5/16", which is 7.9375").