• 521092/D Lid, Air Filter – Thunderbird 350 UCE airbox top cover
  • Thunderbird 350 airbox cover (OEM) – part 521092/D
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UNDER THE HOOD

521092/D – Lid, Air Filter (Airbox Top Cover) for Thunderbird 350 UCE (TBTS BS3 & BS4/ABS “NTB 350”) – Genuine Royal Enfield

521092/D – Lid, Air Filter (Airbox Top Cover) for Thunderbird 350 UCE (TBTS BS3 & BS4/ABS “NTB 350”) – Genuine Royal Enfield

Rs. 118.00
Rs. 120.00 Rs. 118.00
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Important Order Policy
Please order only after confirming the part number, model, variant, year, side, connector type and compatibility. All orders are non-cancellable once placed. Correctly shipped spare parts are not eligible for return, exchange or refund due to wrong selection, wrong diagnosis, fitment mismatch, mechanic recommendation or change of mind. Electrical/electronic items are additionally non-returnable once opened, installed, plugged in, tested or used. Wrong item, damaged item or missing item claims require a complete unboxing video within 24 hours. Read full Return & Warranty Policy

Restore a dust-tight seal on your Thunderbird’s intake with the genuine Royal Enfield 521092/D – Lid, Air Filter. This is the airbox top cover that clamps the filter element inside the OE air cleaner housing on Thunderbird 350 UCE models (listed in fiches as TBTS and BS4/ABS “NTB 350”). Because it’s OEM, the lip profile, latch/fastener locations and moulded seal land match factory spec, so it seats flat on the Air Filter Body and prevents dust or water from bypassing the element—something universal lids cannot guarantee.

Use this part when your existing lid is warped, cracked, missing clips/screws, or not sealing after a fall/over-tightening. Pair it with a fresh filter element and check the snorkel and drain for a like-new intake. We verified the official name and supersession as “LID, AIR FILTER – 521092/D”, with dealer pages mapping it specifically to Thunderbird 350 (TBTS / NTB 350). To minimize returns, we list only confirmed fitment below. 

Key Features

  • Genuine OEM Lid, Air Filter – Part 521092/D (replaces 521092). 

  • Correct OE seal land & mounting points for dust-tight closure. 

  • Plug-and-play on stock airbox—no drilling or trimming.

  • Restores proper filtration and intake noise characteristics.

  • Ideal fix for lids that are warped/cracked or missing hardware.

  • Ships in OE-labelled packaging with GST invoice.

Compatibility Table

Model Engine / Platform BS Stage / Years Notes
Thunderbird 350 (TBTS) 346 cc UCE BS3 (~2009–2012) Listed as LID, AIR FILTER 521092/D. 
Thunderbird 350 (ABS / “NTB 350”) 346 cc UCE BS4 (~2017–2020) Dealer mapping to NTB 350 (ABS BS4).

Not confirmed / excluded: Thunderbird 500, Classic/Bullet/Electra UCE, J-Series (Classic Reborn/Bullet 350 J/Meteor), Himalayan/Scram, Twins 650. Order only for TB 350 unless we VIN-verify otherwise.

Variants / Related 

  • 521091/D – Air Filter Body (airbox lower shell); 521093/D – Cover, Filter Element (front service cover); 521094/A – Beading (seal). These appear alongside 521092/D in the same fiche block.

FAQs

Q1. Is this the complete air filter assembly?
No—this is the lid (top cover) only. For the full unit, order the Air Filter Assembly specific to your TB 350.

Q2. Will it fit Thunderbird 350 BS4 ABS?
Yes—dealer listings show 521092/D for NTB 350 (ABS/BS4). 

Q3. Do I need a new seal or screws?
Re-use good hardware if undamaged. If the beading/seal is flattened or torn, replace (521094/A). 

Q4. How do I confirm for my VIN?
Share your VIN; we’ll fiche-check the exact airbox variant before dispatch.

Verify Fitment on Official Brand Portals

For selected genuine spare parts, you can cross-check the part number on the official brand portals before ordering.

Royal Enfield Official Spares Portal

Hero MotoCorp Official eCatalogue

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