Locate the leak or list the joints you will open before ordering gaskets for a 1980 CB900C Custom. A cover gasket, shaft seal and top-end set solve different ordering needs; the number of pieces in a package matters too.
1979 Honda CB750F Motorcycle Parts1979 Honda CB750K Motorcycle Parts1979 Honda CB750L Motorcycle Parts1980 Honda CB750C Motorcycle Parts1980 Honda CB750F Motorcycle Parts1980 Honda CB750K Motorcycle Parts1980 Honda CB900C Motorcycle Parts1981 Honda CB750C Motorcycle Parts1981 Honda CB750F Motorcycle Parts1981 Honda CB750K Motorcycle Parts1981 Honda CB900C Motorcycle Parts1981 Honda CB900F Motorcycle Parts1982 Honda CB750C Motorcycle Parts1982 Honda CB750F Motorcycle Parts1982 Honda CB750K Motorcycle Parts1982 Honda CB750SC Motorcycle Parts1982 Honda CB900C Motorcycle Parts1982 Honda CB900F Motorcycle Parts1983 Honda CB1000C Motorcycle Parts1983 Honda CB1100F Motorcycle Parts1983 Honda CB750SC Motorcycle PartsHonda CB Electrical & Ignition PartsHonda CB Engine Gaskets, Oil Seals & HardwareHonda CB Engine PartsHonda CB Starter & Charging System PartsHonda CB1000 Motorcycle Parts by Model & YearHonda CB750 DOHC Parts (1979–1982)Honda CB750 Motorcycle Parts by Model & YearHonda CB750C Custom Motorcycle Parts (1980–1982)Honda CB750F Motorcycle Parts (1975–1982)Honda CB750K Motorcycle Parts (1969–1982)Honda CB750SC Nighthawk Motorcycle Parts (1982–1986)Honda CB900 Motorcycle Parts by Model & YearHonda CB900C Custom Motorcycle Parts (1980–1982)Honda CB900F Supersport Motorcycle Parts (1981–1982)Series 3: CB700-750SC (82-86)Series 4: CB900-1100 (80-83)
Replace the alternator cover gasket on your DOHC CB with this Alternator Cover Gasket, replacing OEM #11691-425-000. Fits the 1979-82 CB750 family, CB750SC Nighthawk,...
1979 Honda CB750F Motorcycle Parts1979 Honda CB750K Motorcycle Parts1979 Honda CB750L Motorcycle Parts1980 Honda CB750C Motorcycle Parts1980 Honda CB750F Motorcycle Parts1980 Honda CB750K Motorcycle Parts1980 Honda CB900C Motorcycle Parts1981 Honda CB750C Motorcycle Parts1981 Honda CB750F Motorcycle Parts1981 Honda CB750K Motorcycle Parts1981 Honda CB900C Motorcycle Parts1981 Honda CB900F Motorcycle Parts1982 Honda CB750C Motorcycle Parts1982 Honda CB750F Motorcycle Parts1982 Honda CB750K Motorcycle Parts1982 Honda CB750SC Motorcycle Parts1982 Honda CB900C Motorcycle Parts1982 Honda CB900F Motorcycle Parts1983 Honda CB1000C Motorcycle Parts1983 Honda CB1100F Motorcycle Parts1983 Honda CB750SC Motorcycle PartsHonda CB Engine Gaskets, Oil Seals & HardwareHonda CB Engine PartsHonda CB1000 Motorcycle Parts by Model & YearHonda CB750 DOHC Parts (1979–1982)Honda CB750 Motorcycle Parts by Model & YearHonda CB750C Custom Motorcycle Parts (1980–1982)Honda CB750F Motorcycle Parts (1975–1982)Honda CB750K Motorcycle Parts (1969–1982)Honda CB750SC Nighthawk Motorcycle Parts (1982–1986)Honda CB900 Motorcycle Parts by Model & YearHonda CB900C Custom Motorcycle Parts (1980–1982)Honda CB900F Supersport Motorcycle Parts (1981–1982)Series 3: CB700-750SC (82-86)Series 4: CB900-1100 (80-83)
Replace your DOHC CB's left crankcase (generator) cover gasket with this Generator Cover Gasket, replacing OEM #11395-425-306.Key Features• Left crankcase / generator cover gasket•...
1976 Honda CB750A Motorcycle Parts1977 Honda CB750A Motorcycle Parts1978 Honda CB750A Motorcycle Parts1979 Honda CB750F Motorcycle Parts1979 Honda CB750K Motorcycle Parts1979 Honda CB750L Motorcycle Parts1980 Honda CB750C Motorcycle Parts1980 Honda CB750F Motorcycle Parts1980 Honda CB750K Motorcycle Parts1980 Honda CB900C Motorcycle Parts1981 Honda CB750C Motorcycle Parts1981 Honda CB750F Motorcycle Parts1981 Honda CB750K Motorcycle Parts1981 Honda CB900C Motorcycle Parts1981 Honda CB900F Motorcycle Parts1982 Honda CB750C Motorcycle Parts1982 Honda CB750F Motorcycle Parts1982 Honda CB750K Motorcycle Parts1982 Honda CB750SC Motorcycle Parts1982 Honda CB900C Motorcycle Parts1982 Honda CB900F Motorcycle Parts1983 Honda CB1000C Motorcycle Parts1983 Honda CB1100F Motorcycle Parts1983 Honda CB750SC Motorcycle PartsHonda CB Engine Gaskets, Oil Seals & HardwareHonda CB Engine PartsHonda CB1000 Motorcycle Parts by Model & YearHonda 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 CB750C Custom Motorcycle Parts (1980–1982)Honda CB750F Motorcycle Parts (1975–1982)Honda CB750K Motorcycle Parts (1969–1982)Honda CB750SC Nighthawk Motorcycle Parts (1982–1986)Honda CB900 Motorcycle Parts by Model & YearHonda CB900C Custom Motorcycle Parts (1980–1982)Honda CB900F Supersport Motorcycle Parts (1981–1982)Series 3: CB700-750SC (82-86)Series 4: CB900-1100 (80-83)
Replace your DOHC CB's oil pan gasket with this Oil Pan Gasket, replacing OEM #11398-425-306. Broad fitment across the CB750A Hondamatic, full 1979-82 CB750...
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 CB750F Motorcycle Parts1979 Honda CB750K Motorcycle Parts1979 Honda CB750L Motorcycle Parts1980 Honda CB750C Motorcycle Parts1980 Honda CB750F Motorcycle Parts1980 Honda CB750K Motorcycle Parts1980 Honda CB900C Motorcycle Parts1981 Honda CB750C Motorcycle Parts1981 Honda CB750F Motorcycle Parts1981 Honda CB750K Motorcycle Parts1981 Honda CB900C Motorcycle Parts1981 Honda CB900F Motorcycle Parts1982 Honda CB750C Motorcycle Parts1982 Honda CB750F Motorcycle Parts1982 Honda CB750K Motorcycle Parts1982 Honda CB750SC Motorcycle Parts1982 Honda CB900C Motorcycle Parts1982 Honda CB900F Motorcycle Parts1983 Honda CB1000C Motorcycle Parts1983 Honda CB1100F Motorcycle Parts1983 Honda CB750SC Motorcycle PartsHonda CB Cam Chains, Guides & TensionersHonda CB Engine Gaskets, Oil Seals & HardwareHonda CB Engine PartsHonda CB1000 Motorcycle Parts by Model & YearHonda CB750 DOHC Parts (1979–1982)Honda CB750 Motorcycle Parts by Model & YearHonda CB750C Custom Motorcycle Parts (1980–1982)Honda CB750F Motorcycle Parts (1975–1982)Honda CB750K Motorcycle Parts (1969–1982)Honda CB750SC Nighthawk Motorcycle Parts (1982–1986)Honda CB900 Motorcycle Parts by Model & YearHonda CB900C Custom Motorcycle Parts (1980–1982)Honda CB900F Supersport Motorcycle Parts (1981–1982)Series 3: CB700-750SC (82-86)Series 4: CB900-1100 (80-83)
Replace your DOHC CB's camshaft holder seal with this Camshaft Holder Rubber Seal (triangular piece with rounded corners), replacing OEM #91311-425-000. One piece required...
Replace your DOHC CB's cylinder head gasket with this Athena Premium Quality Cylinder Head Gasket, replacing OEM #12251-438-023.Key Features• Athena premium cylinder head gasket•...
1979 Honda CB750F Motorcycle Parts1979 Honda CB750K Motorcycle Parts1979 Honda CB750L Motorcycle Parts1980 Honda CB750C Motorcycle Parts1980 Honda CB750F Motorcycle Parts1980 Honda CB750K Motorcycle Parts1980 Honda CB750P Motorcycle Parts1980 Honda CB900C Motorcycle Parts1981 Honda CB750C Motorcycle Parts1981 Honda CB750F Motorcycle Parts1981 Honda CB750K Motorcycle Parts1981 Honda CB900C Motorcycle Parts1981 Honda CB900F Motorcycle Parts1982 Honda CB750C Motorcycle Parts1982 Honda CB750F Motorcycle Parts1982 Honda CB750K Motorcycle Parts1982 Honda CB750SC Motorcycle Parts1982 Honda CB900C Motorcycle Parts1982 Honda CB900F Motorcycle Parts1983 Honda CB1000C Motorcycle Parts1983 Honda CB1100F Motorcycle Parts1983 Honda CB750SC Motorcycle PartsHonda CB Engine Gaskets, Oil Seals & HardwareHonda CB Engine PartsHonda CB1000 Motorcycle Parts by Model & YearHonda CB750 DOHC Parts (1979–1982)Honda CB750 Motorcycle Parts by Model & YearHonda CB750C Custom Motorcycle Parts (1980–1982)Honda CB750F Motorcycle Parts (1975–1982)Honda CB750K Motorcycle Parts (1969–1982)Honda CB750P Police Motorcycle Parts (1976, 1978–1980)Honda CB750SC Nighthawk Motorcycle Parts (1982–1986)Honda CB900 Motorcycle Parts by Model & YearHonda CB900C Custom Motorcycle Parts (1980–1982)Honda CB900F Supersport Motorcycle Parts (1981–1982)Series 3: CB700-750SC (82-86)Series 4: CB900-1100 (80-83)
Replace your countershaft oil seal with this Countershaft Oil Seal, 40 x 62 x 13.5, replacing OEM #91205-425-003. High-quality, made in Japan.Key Features• Countershaft...
Replace your DOHC CB's cylinder base gasket with this Athena Premium Quality Cylinder Base Gasket, replacing OEM #12191-425-306.Key Features• Athena premium cylinder base gasket•...
1979 Honda CB750F Motorcycle Parts1979 Honda CB750K Motorcycle Parts1979 Honda CB750L Motorcycle Parts1980 Honda CB750C Motorcycle Parts1980 Honda CB750F Motorcycle Parts1980 Honda CB750K Motorcycle Parts1980 Honda CB900C Motorcycle Parts1981 Honda CB750C Motorcycle Parts1981 Honda CB750F Motorcycle Parts1981 Honda CB750K Motorcycle Parts1981 Honda CB900C Motorcycle Parts1981 Honda CB900F Motorcycle Parts1982 Honda CB750C Motorcycle Parts1982 Honda CB750F Motorcycle Parts1982 Honda CB750K Motorcycle Parts1982 Honda CB750SC Motorcycle Parts1982 Honda CB900C Motorcycle Parts1982 Honda CB900F Motorcycle Parts1983 Honda CB1000C Motorcycle Parts1983 Honda CB1100F Motorcycle Parts1983 Honda CB750SC Motorcycle PartsHonda CB Electrical & Ignition PartsHonda CB Engine Covers & AccessoriesHonda CB Engine Gaskets, Oil Seals & HardwareHonda CB Engine PartsHonda CB Starter & Charging System PartsHonda CB1000 Motorcycle Parts by Model & YearHonda CB750 DOHC Parts (1979–1982)Honda CB750 Motorcycle Parts by Model & YearHonda CB750C Custom Motorcycle Parts (1980–1982)Honda CB750F Motorcycle Parts (1975–1982)Honda CB750K Motorcycle Parts (1969–1982)Honda CB750SC Nighthawk Motorcycle Parts (1982–1986)Honda CB900 Motorcycle Parts by Model & YearHonda CB900C Custom Motorcycle Parts (1980–1982)Honda CB900F Supersport Motorcycle Parts (1981–1982)Series 3: CB700-750SC (82-86)Series 4: CB900-1100 (80-83)
Starter Motor Cover Gasket ~ Replaces Honda OEM 31282-425-300 for the Honda CB models listed below. Use this part for repair, restoration, or replacement...
1979 Honda CB750F Motorcycle Parts1979 Honda CB750K Motorcycle Parts1979 Honda CB750L Motorcycle Parts1980 Honda CB750C Motorcycle Parts1980 Honda CB750F Motorcycle Parts1980 Honda CB750K Motorcycle Parts1980 Honda CB900C Motorcycle Parts1981 Honda CB750C Motorcycle Parts1981 Honda CB750F Motorcycle Parts1981 Honda CB750K Motorcycle Parts1981 Honda CB900C Motorcycle Parts1981 Honda CB900F Motorcycle Parts1982 Honda CB750C Motorcycle Parts1982 Honda CB750F Motorcycle Parts1982 Honda CB750K Motorcycle Parts1982 Honda CB750SC Motorcycle Parts1982 Honda CB900C Motorcycle Parts1982 Honda CB900F Motorcycle Parts1983 Honda CB1000C Motorcycle Parts1983 Honda CB1100F Motorcycle Parts1983 Honda CB750SC Motorcycle PartsHonda CB Engine Gaskets, Oil Seals & HardwareHonda CB Engine PartsHonda CB1000 Motorcycle Parts by Model & YearHonda CB750 DOHC Parts (1979–1982)Honda CB750 Motorcycle Parts by Model & YearHonda CB750C Custom Motorcycle Parts (1980–1982)Honda CB750F Motorcycle Parts (1975–1982)Honda CB750K Motorcycle Parts (1969–1982)Honda CB750SC Nighthawk Motorcycle Parts (1982–1986)Honda CB900 Motorcycle Parts by Model & YearHonda CB900C Custom Motorcycle Parts (1980–1982)Honda CB900F Supersport Motorcycle Parts (1981–1982)Series 3: CB700-750SC (82-86)Series 4: CB900-1100 (80-83)
Replace your crankshaft seal with this Crankshaft Seal, 25 x 42 x 8, replacing OEM #91201-425-003. High-quality, made in Japan.Key Features• Crankshaft Seal• 25...
Rebuild your CB900C or CB900F engine with this Athena Overhaul Gasket Set. Athena of Italy is an original-equipment supplier to Yamaha, Honda, Kawasaki, Suzuki,...
Cylinder Base Gasket ~ Replaces Honda OEM 12191-425-306 for the Honda CB models listed below. Use this part for repair, restoration, or replacement work...
Cylinder Head Gasket ~ Replaces Honda OEM 12251-438-023 for the Honda CB models listed below. Use this part for repair, restoration, or replacement work...
Replace your DOHC CB's cylinder sleeve O-rings with this Cylinder Sleeve O-Rings Set of 4, replacing OEM #91302-425-000. Four pieces required per engine.Key Features•...
Oil can travel across a cover before it drips. Clean the area and identify the first wet joint, then distinguish the head-cover gasket, head or base gasket, and the seal around a moving shaft. Their repair scope is very different on the CB900C.
A head-cover repair is different from head removal
The head-cover gasket is disturbed for valve-clearance service. Honda specifies checking it for damage and applying sealant only at the locations shown in the cover procedure. Removing the cylinder head or block is a larger, engine-out job with head, base and other seals to account for; the top-end set does not promise every engine oil seal.
Match shaft seals to the damaged location
The shift-shaft seal is listed as 12.5 × 25 × 8mm. Check that exact position and the shaft’s sealing surface before fitting a replacement. A new seal cannot correct a damaged shaft or a distorted cover. Keep cylinder-sleeve O-rings separate from valve-stem seals and account for any pieces already included in a gasket set.
Buying questions
Should the whole valve-cover gasket be coated in sealant?
Follow Honda’s head-cover diagram. It identifies particular sealing points rather than a full coating. Inspect the gasket and cover first; extra sealant or excessive tightening is not a repair for damaged rubber or a distorted sealing face.
Does a leak near the shift lever call for a top-end gasket set?
First trace the oil to its source. If it starts at the shift shaft, inspect that shaft and its individual seal. A head or base gasket set serves different joints and will not repair a shaft-seal leak.
How do I decide between separate gaskets and the top-end set?
List every joint the planned work will open and compare the itemized contents. The Athena set includes head, base and head-cover gaskets, exhaust gaskets and selected seals. Buy separate parts for uncovered joints or a limited repair, without duplicating included sleeve O-rings.
Not sure which part you need?
Send your model and year, plus photos of your existing part and any changes to the original setup.