VintageCB750 Supplying CB Riders Since 2010

About Us Why Us? Reviews Shipping Info Returns Contact Us
Wish Lists
0 My Cart

Your cart is currently empty.

Browse all parts
Total (USD): $0.00
View cart
Menu
Search
Wish
Cart 0
My motorcycle Choose your Honda CB model

Search parts

Searching all Honda CB parts

Example: brake pads or oil filter.

1978 Honda CB400A Exhaust Gaskets

Exhaust gasket orders are easiest to get right when each disturbed connection is identified first. The CB400A choices include a cylinder-head port seal, a headpipe joint seal and a crossover gasket. Separate those locations from package quantity before rebuilding the fitted exhaust.

Close ×
Your saved bike Choose your Honda CB model

Shop By Category

Most orders ship same or next business day Fitment guarantee Listed for your exact model and year? We’ll make it right if it doesn’t fit as described. Mechanic-backed support Ask our team for help choosing the right Honda CB part.
Currently viewing Gaskets & Mounting Hardware

Honda motorcycle parts

Choose your model and year to see parts listed for your bike.

Honda CB900 CB650 CB550 exhaust headpipe gasket (each) 18212-634-000

Honda CB Exhaust Headpipe Gasket (Each) ~ Replaces 18212-634-000

$3.58 USD
17-2813
Replace one exhaust port gasket on your CB650, CB400, CB450, or modern CB900F with this Exhaust Port Gasket, 1 piece, replacing OEM #18212-634-000 /...
Honda CB900 CB650 CB550 exhaust headpipe gaskets (pk 10) 18212-634-000

Honda CB Exhaust Headpipe Gaskets ~ (Pk/10) ~ Replaces 18212-634-000

$27.95 USD
17-3813
Stock up on exhaust port gaskets for your CB650, CB400, CB450, or modern CB900F with this 10-pack, replacing OEM #18212-634-000 / #18291-236-000 / #18291-MN4-920.Key...
Sold out
Honda CB450 CB400 exhaust joint gasket for headpipe 18391-413-000

1978-86 Honda CB450 / CB400 Exhaust Joint Gasket for Headpipe ~ Replaces 18391-413-000

$10.73 USD
17-4504
Replace your CB400 or CB450 exhaust joint gasket with this Exhaust Joint Gasket for Headpipe, replacing OEM #18391-413-000 / #18391-413-010.Key Features• Exhaust joint gasket...
Honda CB750 CB650 CB550 CB450 exhaust crossover gasket 18392-413-000

Honda CB Exhaust Crossover Gasket ~ Replaces 18392-413-000

$9.95 USD
17-4505
Replace your Nighthawk or CB400/CB450 exhaust crossover gasket with this Exhaust Crossover Gasket, replacing OEM #18392-413-000 / #18392-MG7-750. Fits the mid-'80s CB750SC/CB650SC/CB550SC Nighthawks plus...
compare

1978 Honda CB400A · Exhaust Gaskets Buying guide

Map each gasket to its exhaust connection

The port gasket comes individually or in a ten-pack. Headpipe and crossover seals use different reference numbers for different joints. Check the fitted exhaust layout before ordering, especially when the system has been changed from standard.

Parts to consider

Honda CB Exhaust Headpipe Gasket (Each) ~ Replaces 18212-634-000 Individual exhaust-port gasketOne gasket per order, referencing 18212-634-000, 18291-236-000 and 18291-MN4-920.View part 1978-86 Honda CB450 / CB400 Exhaust Joint Gasket for Headpipe ~ Replaces 18391-413-000 Headpipe joint gasketCB400A headpipe-joint application referencing 18391-413-000 and 18391-413-010.View part Honda CB Exhaust Crossover Gasket ~ Replaces 18392-413-000 Crossover joint gasketReplaces reference 18392-413-000 / 18392-MG7-750 at the specified exhaust connection.View part

Related parts: Port-gasket pack of ten

Choose the correct joint family

The port gasket references 18212-634-000, 18291-236-000 and 18291-MN4-920. Headpipe and crossover seals use separate reference families. Compare the location and mating parts, because the common CB400A application describes the motorcycle rather than one interchangeable seal for every exhaust joint.

Separate package size from the repair quantity

The individual port-seal option supplies one gasket; the alternative package supplies ten. Work out how many port connections the repair disturbs before choosing between them. Headpipe and crossover seals remain separate selections and are not converted into a complete system set by adding port gaskets.

Exhaust Gaskets questions

How many gaskets are in the individual port-gasket order?

One. The individual item is explicitly supplied as one exhaust-port gasket. A separate ten-pack is available if that quantity suits the work; the ten-pack is not a statement of the motorcycle’s requirement.

Which reference distinguishes the headpipe joint seal?

The headpipe joint gasket uses 18391-413-000 / 18391-413-010. The crossover seal instead references 18392-413-000 / 18392-MG7-750. Use the joint location and original component to choose between them.

Will these seals fit a nonstandard exhaust?

Check the replacement exhaust manufacturer’s joint design and specifications. These CB400A applications do not guarantee compatibility after a collector, headpipe or muffler conversion, even if the system bolts to the original engine.

Not sure which part you need?

Send your model and year, plus photos of your existing part and any changes to the original setup.

Ask a fitment question
Parts categories for 1978 Honda CB400A

Your cart

×