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  • 1978-79 Honda CB400 Air Cut Off Valve ~ Replaces 16048-425-671
Honda CB400 air cut off valve 16048-425-671
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Honda CB400 air cut off valve 16048-425-671

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1978-79 Honda CB400 Air Cut Off Valve ~ Replaces 16048-425-671

20-4022
$27.03 USD
In stock Usually ships the same or next business day
Check model fitment View fitment
Questions about this part? Contact us 4.8/5 1,347 store reviews
Secure checkoutProtected payment
60-day returnsEligible unused parts Free ground shippingUSA & Canada over $50
Browse all parts
1978-79 Honda CB400 Air Cut Off Valve ~ Replaces 16048-425-671
$27.03 USD
Description

Replace your CB400's carb air cut-off valve with this Carb Air Cut-Off Valve, replacing OEM #16048-425-671 (diaphragm) plus spring and O-ring.

Key Features
• Carb air cut-off valve
• Replaces OEM #16048-425-671 (diaphragm) + spring + O-ring
• Honda part name: Valve Set, Air Cut

Fitment / Compatibility
• Honda CB400A (1978)
• CB400TI (1978‑79)
• CB400TII (1978‑79)

Part Number: 20-4022

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Check the listed model and year, then read any fitment notes in the description.

Make Model Year
Honda CB400A 1978
Honda CB400TI Hawk 1978
Honda CB400TIZ Hawk 1979
Honda CB400TII Hawk 1978
Honda CB400TIIZ Hawk 1979
Honda CB400TII Hawk 1978
Honda CB400TIIZ Hawk 1979

Free ground shipping over $50

To the USA & Canada. In-stock orders usually ship from our own warehouse the same or next business day.

Estimated ground delivery after your order ships
DestinationDelivery time
USA4–7 business days
Canada2–6 business days

Ground shipping includes tracking, emailed when your order ships. Need it sooner? Express options are available at checkout.

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60-day returns on eligible parts

No restocking fees. Eligible parts must be unused, uninstalled, unaltered and complete. The 60-day window starts when your order is delivered.

Electrical parts are excluded from standard returns. Check return eligibility.

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Other shipping options

Canada Post Economy: Available at checkout for select small items. Allow 1–3 weeks for delivery. No tracking or insurance is included.

Outside the USA & Canada: Delivery times vary by destination and shipping method. Buyers are responsible for applicable duties, taxes and import fees. We cannot mark orders as gifts.

Frequently Asked Questions

What is included with air cut-off valve kit 20-4022?

The kit includes one diaphragm, one spring and one O-ring for servicing a compatible carburetor air cut-off valve.

Which Honda air cut-off valve number does 20-4022 replace?

The diaphragm cross-references Honda OEM 16048-425-671 for the listed 1978-1979 CB400 applications.

What can a failed carburetor air cut-off diaphragm cause?

A hardened, split or leaking diaphragm can upset the deceleration fuel circuit and contribute to popping or unstable running when the throttle closes.

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