
The facts.
| Brand | K-Tech |
|---|---|
| Part Number | FSK-003 |
| Seal Manufacturer | NOK |
| Inner Diameter | 37.00 mm |
| Outer Diameter | 50.00 mm |
| Contents | 2x oil seals, 2x dust caps |
| Fitment | Kawasaki ZX-4RR (2023–2026) |
| Intended Use | Fork oil seal and dust cap replacement |
DescriptionThe whole story▼
Precision-engineered from NOK-sourced sealing compounds, the K-Tech FSK-003 fork oil seal and dust cap kit is built to the tolerances that serious ZX-4RR riders demand. Designed specifically for the 2023–2026 Kawasaki ZX-4RR, this kit restores factory-tight fork sealing integrity and guards against the contamination that degrades suspension performance over time.
Key Features
- NOK-manufactured oil seals — a globally trusted name in high-performance sealing technology, chosen for durability and dimensional consistency
- Precision inner diameter of 37.00 mm and outer diameter of 50.00 mm, machined to exact OEM tolerances for a leak-free fit
- Dual dust caps form a physical barrier against road grit, mud and moisture reaching the fork leg surfaces
- Prevents fork oil loss that would otherwise compromise damping response and rider feedback
- Extends fork service life by maintaining the clean, oil-rich environment the damping internals depend on
- Part number FSK-003 ensures correct identification when ordering or cross-referencing with K-Tech service centres
Build Quality & Materials
K-Tech has specified NOK seals for this kit rather than generic alternatives — a deliberate choice that reflects the brand's commitment to components that perform under sustained stress. NOK is recognised across motorsport and OEM production for the consistency of its rubber compounds and dimensional accuracy. Each oil seal in this kit is manufactured to resist the thermal cycling and pressure fluctuations inherent in hard road and track use, while the dust caps provide a close-tolerance interference fit that stays in place even after repeated fork cycles.
Performance & Reliability
Worn or weeping fork seals are one of the most common causes of degraded suspension feel on any sportsbike. Once fork oil escapes past a failing seal, it contaminates the brake rotor and tyre, turning a maintenance issue into a safety concern. Replacing seals at the correct service interval with a quality kit like the FSK-003 keeps the ZX-4RR's suspension performing as Kawasaki intended — consistent spring rates, predictable damping and confident braking.
Installation Note
Fork seal replacement requires specialist tools and technical knowledge to ensure correct seating depth and avoid damage to the fork tubes. K-Tech recommends installation be carried out by an authorised K-Tech Service Centre to guarantee optimal function and safety.
Fitment & Compatibility
- Kawasaki ZX-4RR — 2023, 2024, 2025, 2026
Specifications
| Attribute | Detail |
|---|---|
| Part Number | FSK-003 |
| Inner Diameter | 37.00 mm |
| Outer Diameter | 50.00 mm |
| Seal Manufacturer | NOK |
| Contents | 2x oil seals, 2x dust caps |
| Fitment | Kawasaki ZX-4RR (2023–2026) |
What's includedEverything in the box▼
- 2x oil seals (fork oil seals)
- 2x dust caps
FitmentWhich bikes this fits▼
- Kawasaki ZX-4RR (2023–2026)
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