Restore your Bullet’s factory thump and compliance with the Genuine Royal Enfield Silencer Assembly (BS4) – Part 576623/A. This is the stock OE muffler supplied by Royal Enfield, engineered for the UCE platform to meet BSIV (BS4) noise and emissions norms while preserving back-pressure and reliability. Unlike aftermarket cans, this unit uses OEM internals and packing for durability on daily rides and long tours, and it bolts straight on with factory mounts and clamps (order clamps/gaskets separately if your old ones are worn). Ideal when your original muffler is dented, rusted, or failing emissions/sound checks, or if you’ve reverted from an aftermarket exhaust and want stock smoothness and mileage back. Choose genuine to avoid fitment hassles and reduce returns. Verified in the official parts fiche as “Silencer assy BSIV” under P/N 576623/A. 

Key Features:

• 100% Genuine Royal Enfield OE part – P/N 576623/A (BS4). 

• Built for UCE engine platform; maintains factory back-pressure & tuning. 

• BSIV compliant for noise & emissions (street-legal where BS4 applies). 

• Direct bolt-on with OEM brackets; no fabrication required (use fresh clamp/gasket). 

• Durable OE materials & finish for long service life. 

• Best choice to reduce returns vs. non-OE aftermarket cans. 

Compatibility Table:

(Only models confirmed are listed. Anything unconfirmed is marked 

Not compatible:

• Classic 350/500 UCE stock silencers use different OE part numbers (e.g., Classic family P/N series like 591860/N), so do not use 576623/A on Classics. 

• All BS6/J-series bikes (Classic Reborn, Bullet 350 J, Meteor, Hunter, etc.) – completely different exhausts. (BS6 ≠ BS4). 

Variants:

• Finish: OE Chrome Silencer Assembly (single piece).

• Side: Not applicable (center/right single muffler).

• What’s included: Silencer assembly only. Heat shield/guard, clamp & gasket sold separately (order if required). 

FAQs:

Q1: Will this fit BS6 (2020+) Bullet/Classic Reborn (J-series)?
A: No. This is BS4 (BSIV) only. J-series/BS6 models use completely different exhaust designs. 

Q2: Does it include the heat shield, clamp or gasket?
A: The part is the silencer assembly. Order clamp/guard/gasket separately if your existing hardware is worn. 

Q3: Is it louder than stock?
A: No. It is the stock Royal Enfield muffler and meets BSIV noise/emissions levels. 

Q4: Will this fit Classic 350/500 UCE?
A: No. Classic models use different OE silencer part numbers; use Classic-specific parts instead.