1978 Honda CB750K Parts

Parts and fitment guide for your 1978 CB750K (K8)

Find listed parts for 1978 Honda CB750K maintenance, including an accelerator-pump diaphragm, stock-airbox filter and replacement front caliper. Compare the installed carburetors and brake assembly before choosing parts for a restored or modified K model.

Browse by repair

• Engine parts — filters, seals and engine components.
• Fuel-system parts — carburetors, air filters and fuel delivery.
• Electrical parts — ignition, switches and charging parts.
• Brake & clutch parts — braking and clutch components.
• Suspension & wheels — fork seals, bearings and suspension parts.
• Exhaust parts — exhaust components, gaskets and hardware.

Selected parts for the 1978 CB750K

Check each listing for model fitment, dimensions and what is included before ordering.

• Carb pump diaphragm — diaphragm with rod and bellows rubber for the listed Keihin accelerator pump.
• Stock air filter — stock-airbox replacement referenced to 17211-405-000.
• Front brake caliper — sold each; compare the listed 51mm mounting spacing with the fitted brake.

Identify your CB750K8 (1978)

Record the complete frame or VIN marking and the engine stamping before ordering model-specific parts. Match them to Honda documentation for the motorcycle’s original market.

• Frame number — copy every stamped character, including the prefix.
• Engine number — record the complete marking separately from the frame number.

Use the linked chart as a model reference alongside original-market records. Its starting entry alone does not establish a production cutoff or build date.

View the CB750 reference chart

For help locating and comparing identifiers, see our Honda CB model identification guide.

Separate accelerator-pump service from a carburetor rebuild

The linked 20-9040 pump repair listing supplies one diaphragm with its rod and one bellows rubber. It is an accelerator-pump component, not a complete carburetor rebuild kit. Compare the removed assembly and the listing’s replacement references: 16021-393-004, 16021-393-014 and 16021-MC9-771.

The linked 33-0041 front caliper assembly lists the 1977–78 CB750K and 51mm mounting spacing. It includes the caliper body halves, pads, piston, piston seal, bleed screw, cap and bolts, and is sold each. Have the fitted caliper and the rest of the brake system checked before installation.

Related CB750K collections

• 1977 CB750K parts
• All CB750K parts

Need help checking a part? Contact VintageCB750 with your model, frame and engine numbers, and photos of the component you are replacing.