For a leaking or dismantled exhaust-port joint on the 1982 CB900C Custom, start with the gasket’s location and the number of joints being opened. The headpipe gasket here is supplied individually, so a repair involving several pipes needs a deliberately counted order.
Replace one exhaust port gasket on your CB750 or big-bore DOHC CB with this Exhaust Port Gasket, 1 piece, replacing OEM #18291-254-000 / #18291-MM5-860....
1967 Honda CL450K0 Motorcycle Parts1968 Honda CB350K0 Motorcycle Parts1969 Honda CB175K3 Motorcycle Parts1969 Honda CB750K Motorcycle Parts1969 Honda CL450K2 Motorcycle Parts1970 Honda CB100K0 Motorcycle Parts1970 Honda CB175K4 Motorcycle Parts1970 Honda CB350K2 Motorcycle Parts1970 Honda CB450K Motorcycle Parts1970 Honda CB750K Motorcycle Parts1970 Honda SL350K0 Motorcycle Parts1971 Honda CB100K1 Motorcycle Parts1971 Honda CB175K1 Motorcycle Parts1971 Honda CB350K3 Motorcycle Parts1971 Honda CB450K Motorcycle Parts1971 Honda CB500K Four Motorcycle Parts1971 Honda CB750K Motorcycle Parts1972 Honda CB100K2 Motorcycle Parts1972 Honda CB175K6 Motorcycle Parts1972 Honda CB350K4 Motorcycle Parts1972 Honda CB450K Motorcycle Parts1972 Honda CB500K Four Motorcycle Parts1972 Honda CB750K Motorcycle Parts1973 Honda CB125S0 Motorcycle Parts1973 Honda CB175K7 Motorcycle Parts1973 Honda CB350G Motorcycle Parts1973 Honda CB500K Four Motorcycle Parts1973 Honda CB750K Motorcycle Parts1974 Honda CB125S1 Motorcycle Parts1974 Honda CB200 Motorcycle Parts1974 Honda CB550K Motorcycle Parts1974 Honda CB750K Motorcycle Parts1974 Honda CL360K0 Motorcycle Parts1975 Honda CB125S2 Motorcycle Parts1975 Honda CB200T Motorcycle Parts1975 Honda CB400F Motorcycle Parts1975 Honda CB500T Twin Motorcycle Parts1975 Honda CB550F Supersport Motorcycle Parts1975 Honda CB550K Motorcycle Parts1975 Honda CB750K Motorcycle Parts1975 Honda CL360K1 Motorcycle Parts1976 Honda CB200TK0 Motorcycle Parts1976 Honda CB400F Motorcycle Parts1976 Honda CB500T Twin Motorcycle Parts1976 Honda CB550F Supersport Motorcycle Parts1976 Honda CB550K Motorcycle Parts1976 Honda CB750A Motorcycle Parts1976 Honda CB750K Motorcycle Parts1977 Honda CB400F Motorcycle Parts1977 Honda CB550F Supersport Motorcycle Parts1977 Honda CB550K Motorcycle Parts1977 Honda CB750A Motorcycle Parts1977 Honda CB750K Motorcycle Parts1978 Honda CB550K Motorcycle Parts1978 Honda CB750A Motorcycle Parts1978 Honda CB750F Motorcycle Parts1978 Honda CB750K Motorcycle Parts1979 Honda CB650 Motorcycle Parts1979 Honda CB750F Motorcycle Parts1979 Honda CB750K Motorcycle Parts1979 Honda CB750L Motorcycle Parts1980 Honda CB650 Motorcycle Parts1980 Honda CB650C Custom Motorcycle Parts1980 Honda CB750F Motorcycle Parts1980 Honda CB750K Motorcycle Parts1980 Honda CB900C Motorcycle Parts1981 Honda CB650 Motorcycle Parts1981 Honda CB650C Custom Motorcycle Parts1981 Honda CB750F Motorcycle Parts1981 Honda CB750K Motorcycle Parts1981 Honda CB900C Motorcycle Parts1981 Honda CB900F Motorcycle Parts1982 Honda CB650 Motorcycle Parts1982 Honda CB650SC Nighthawk Motorcycle Parts1982 Honda CB750F Motorcycle Parts1982 Honda CB750K Motorcycle Parts1982 Honda CB900C Motorcycle Parts1982 Honda CB900F Motorcycle Parts1983 Honda CB1100F Motorcycle Parts1994 Honda CB1000 Motorcycle Parts1995 Honda CB1000 Motorcycle PartsHonda CB Exhaust Gaskets & Mounting HardwareHonda CB Exhaust Systems, Mufflers & HardwareHonda CB Foot Pegs, Shifters, Kickstarters & StandsHonda CB Frame & Body PartsHonda CB Rubber Components & Mounting DampersHonda CB100 Motorcycle Parts by Model & YearHonda CB1000 Motorcycle Parts by Model & YearHonda CB100K Motorcycle Parts (1970–1972)Honda CB125 Motorcycle Parts by Model & YearHonda CB125S Motorcycle Parts (1973–1985)Honda CB175K Motorcycle Parts (1969–1973)Honda CB200 Motorcycle Parts by Model & YearHonda CB200T / CB200TK0 Motorcycle Parts (1975–1976)Honda CB350 Motorcycle Parts by Model & YearHonda CB350K Motorcycle Parts (1968–1972)Honda CB400 Motorcycle Parts by Model & YearHonda CB400F Motorcycle Parts (1975–1977)Honda CB450 Motorcycle Parts by Model & YearHonda CB450K Motorcycle Parts (1965–1974)Honda CB500 Motorcycle Parts by Model & YearHonda CB500K Motorcycle Parts (1971–1973)Honda CB500T Motorcycle Parts (1975–1976)Honda CB550 Motorcycle Parts by Model & YearHonda CB550F Motorcycle Parts (1975–1977)Honda CB550K Motorcycle Parts (1974–1978)Honda CB650 Motorcycle Parts (1979–1982)Honda CB650 Motorcycle Parts by Model & YearHonda CB650C Custom Motorcycle Parts (1980–1981)Honda CB650SC Nighthawk Motorcycle Parts (1982–1985)Honda CB750 DOHC Parts (1979–1982)Honda CB750 Motorcycle Parts by Model & YearHonda CB750 SOHC Parts (1969–1978)Honda CB750A Hondamatic Motorcycle Parts (1976–1978)Honda CB750F Motorcycle Parts (1975–1982)Honda CB750K Motorcycle Parts (1969–1982)Honda CB900 Motorcycle Parts by Model & YearHonda CB900C Custom Motorcycle Parts (1980–1982)Honda CB900F Supersport Motorcycle Parts (1981–1982)Honda CL360K Motorcycle Parts (1974–1975)Honda CL450K Motorcycle Parts (1967–1974)Honda SL350K Motorcycle Parts (1969–1973)Series 10: CB72-CB250 (59-85)Series 4: CB900-1100 (80-83)Series 5: CB650 (79-82)Series 6: CB500-CB550 (71-78)Series 7: CB400-CB450 (65-86)Series 8: CB350-CB400 (72-77)Series 9: CB350-CB360 (69-75)
Replace a worn kick stand stopper with this Kick Stand Stopper Rubber "A", a direct replacement for OEM #95011-61000. Exceptionally broad fitment across the...
Replace one cylinder-head-to-exhaust-headpipe gasket on your big-bore Honda with this Cylinder Head to Exhaust Headpipe Gasket, 1 piece, replacing OEM #18291-MM5-860. Exceptionally broad fitment...
1979 Honda CB750K Motorcycle Parts1980 Honda CB750K Motorcycle Parts1980 Honda CB900C Motorcycle Parts1981 Honda CB750K Motorcycle Parts1981 Honda CB900C Motorcycle Parts1981 Honda CB900F Motorcycle Parts1982 Honda CB750K Motorcycle Parts1982 Honda CB900C Motorcycle Parts1982 Honda CB900F Motorcycle PartsHonda CB Exhaust Gaskets & Mounting HardwareHonda CB Exhaust Systems, Mufflers & HardwareHonda CB750 DOHC Parts (1979–1982)Honda CB750 Motorcycle Parts by Model & YearHonda CB750K Motorcycle Parts (1969–1982)Honda CB900 Motorcycle Parts by Model & YearHonda CB900C Custom Motorcycle Parts (1980–1982)Honda CB900F Supersport Motorcycle Parts (1981–1982)Series 4: CB900-1100 (80-83)
Restore your classic Honda’s exhaust system with this premium Exhaust Stud Set, engineered for durability and a precise fit. This 8-piece kit includes eight...
Count the port joints before ordering individual gaskets
The featured sealing piece fits the cylinder-head-to-headpipe joint and references 18291-MM5-860. Choose it for that location rather than using an exhaust-category label to identify every gasket in a modified system.
The featured gasket is sold individually for the headpipe-to-cylinder-head port. Four are needed when all four ports are resealed. Remove each old crush gasket from a disturbed port before fitting its replacement, and inspect the seating surface rather than stacking a new gasket over the old one.
Keep the order quantity explicit
One purchased gasket supplies one sealing piece. Count the joints being disturbed, and inspect their seating surfaces and fastening hardware before reassembly. Use the service manual for the installation sequence and specifications rather than assuming a new gasket alone resolves damaged mounting parts.
Exhaust Gaskets questions
Can an old port gasket be left beneath the new one?
No. Remove the old crush seal from the disturbed port and inspect the seat before fitting a fresh gasket. A compressed old ring can be easy to overlook; stacking seals is not a substitute for preparing the joint properly.
Are the exhaust joint collars the same parts as the gaskets?
No. The 18233-425-000 product is one joint half-collar, with two used at each cylinder-head pipe joint. The gasket seals inside the port. Match the missing or damaged piece before ordering either product, and inspect the studs, nuts and flanges separately.
Does replacing an exhaust gasket mean all studs must be renewed?
Inspect the studs, nuts, cylinder-head threads and retained pipe flanges first. The gasket serves a separate sealing job; damaged fasteners or threads need their own repair, but opening a joint alone does not prove that every stud must be replaced.
Not sure which part you need?
Send your model and year, plus photos of your existing part and any changes to the original setup.