Flip-Top Gas Cap | Honda CB350 / CB450 / CB550 / CB750 Twins & Fours
The hinged flip-top gas cap on classic Honda twins and fours takes a beating — fuel, weather, and years of thumbing it open leave it pitted, rusty, or warped until it no longer seals. This is an OEM-style replacement that ships as a complete kit: cap, seal, and mounting pin.
Why You Need This
A warped or rusted cap won't seal the tank, which lets moisture in and fuel vapor out. Rather than chase down a clean used one, replace it. This kit gives you the flip-top cap, a fresh gas cap seal, and the mounting pin — everything except the thumb latch, which you re-use from your old cap (or add below).
Specifications
| Spec | Detail |
|---|
| Style | Flip-top (hinged), OEM-style |
| Fits Models | CB200 K0 (1973–1974), CB200T (1975–1976); CL200 Scrambler (1974); CB350 K3–K5 (1971–1973); CL350 Scrambler K3–K5 (1971–1973); SL350 K0–K2 (1969–1973); CB360G (1974), CB360T (1975–1976); CL360 Scrambler K0–K1 (1974–1975); CJ360T (1976); CB450 K3–K7 (1970–1974); CL450 Scrambler K3–K6 (1970–1974); CB500 K0–K2 (1971–1973); CB500T (1975–1976); CB550 K0–K2 (1974–1976); CB750 K0–K6 (1969–1976) |
| Replaces OEM Parts | 17510-323-310, 17510-300-163, 17510-323-999, 17520-300-300, 17523-300-000, 17524-300-000, 17525-300-000, 17526-300-000, 17514-323-300 |
| Sold As | Kit — cap, seal, and mounting pin (sold individually) |
What's in the Kit
- Flip-top gas cap
- Gas cap seal
- Mounting pin
The thumb latch is not included — re-use your original if it's in good shape, or add a replacement using the options above.
Note: This is the hinged flip-top cap. If your bike came with the earlier twist-on (screw-on) cap — any CB175 / CL175, or a CB350 / CL350 / CB450 / CL450 from K0–K2 — you need our Chrome Twist-On Gas Cap instead.
Model-Specific Notes
- The flip-top era: Honda's twins switched from the twist-on cap to this hinged flip-top at K3. It fits the K3-and-later 350s and 450s, the CB200 / CL200, the 360 family (CB360 / CL360 / CJ360), and the CB500 / CB550 / CB750 fours.
- Latch not included: Re-use your original thumb latch, or add our standard latch or locking latch using the options above.
- Does NOT fit the screw-on models: CB175 / CL175 (all years) and CB350 / CL350 / CB450 / CL450 K0–K2 used the twist-on cap.
Installation
Difficulty: Intermediate
- Drive out the original rivet holding your old cap — a very tiny punch or a small finishing nail works well. Take your time if it's corroded.
- Fit the new cap; it's held by a pin secured with a small circlip.
- Re-use your original thumb latch if it's in good shape, or fit a replacement latch.
Seal tip: When you fit the gas cap seal, the thin edge faces the inside of the cap.
Frequently Asked Questions
What comes in the kit?
The flip-top cap, a new gas cap seal, and the mounting pin. The thumb latch is not included — re-use your original if it's in good shape, or add a standard or locking latch using the options above.
How do I get my old cap off?
The original cap is held by a rivet. Drive it out with a very tiny punch or a small finishing nail. The new cap installs with a pin held by a small circlip — no drilling needed.
Does my bike use the flip-top or the twist-on cap?
The flip-top cap is hinged and latched; the twist-on cap screws on. Honda used this flip-top on the K3-and-later 350s and 450s, the CB200 / CL200, the 360 family, and the CB500 / CB550 / CB750 fours. The earlier CB175 / CL175 (all years) and the K0–K2 350s and 450s used the twist-on cap.
Is the locking latch actually keyed?
Not really — the locking latch takes a key, but it isn't cut to a unique code, so most any Honda key will open it. It deters casual tampering rather than acting as true security.
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Last updated: June 2026
