Description
The AIS (Secondary Air System), often erroneously called “EGR” on Hyosung bikes, was a factory addition to meet Euro3 emissions by diluting exhaust gases with fresh air from the airbox. While functional for regulations, it creates massive “popping” when installing aftermarket exhausts and litters the engine bay with vacuum hoses. Removing this system provides a cleaner aesthetic, a stronger vacuum signal for your fuel system, and allows tuners to get a true reading of the air/fuel ratio without airbox dilution.
💎 Professional Build Quality
Our plates are designed to provide a 100% airtight seal, ensuring your engine performance isn’t compromised by vacuum leaks.
| Reduces Backfire Stops the “pop” during gear changes and decel. |
Engine Bay Bling Removes a web of ugly rubber hoses and pipes. |
| Stable Vacuum Better performance for vacuum-fed fuel taps. |
Stainless Hardware Includes high-quality bolts that won’t rust. |
📜 Confirmed Fitment Guide
📅 YEARS: 2005–2019 (Carburettor models only).
⛔ NOT FOR EFI: Fuel-injected models use electronic air pumps; this kit will not be a good idea!
🌍 NOTICE: UK MOT does not currently check emissions on carb bikes (it may change in the future!) . Check local laws if you live outside the UK.
When removing the AIS, you must seal the airbox and manifold vacuum ports. Check our Vacuum Cap & Hose Kits for a professional, leak-free finish. Browse Tuning Accessories.
🔧 Install Tips
- Part 1 – Airbox Blanking:
• 125/250cc owners: Click here
• 650cc owners: Click herePart 2 – Installing the Blanking Plates:
⚠ HyoRiders is not responsible for seized or rusted bolts — take your time or consult a local garage.- Go under the airbox and ensure the air hose is sealed. Leaving it open will cause piston issues.
- Blank off the vacuum pipe on the intake manifold that went to the AiS/EGR system.
- Remove the engine’s EGR/AiS metal pipe.
- Check your gasket or use the new one included. No RTV or silicone!
- Fit your new plates. Do not overtighten the bolts — Hyosung engines use soft alloy!
- Start the bike. Check all connections for leaks or hissing sounds before riding.
Common errors to avoid:
- Leaking airbox hose
- Poor gasket seal on the plate
- Loose intake manifold vacuum cap
- Leaving tools, clips or hoses unsecured
If you’re stuck, ask for help in the links above!
👍 If you’re happy with the result, leave a review or post a photo of your build!
📧 FITMENT QUESTIONS? Email us before ordering.




















Daz (verified owner) –
Bought these EGR blanking plates the other week and they look spot on, were delivered quick too. I’ll upload a picture once I’ve rebuilt the engine.
Cheers