{"product_id":"hk-old-is-gold-db-killer-punjab-silencer-45-57-63mm","title":"Royal Enfield Punjab Silencer DB Killer \/ Sound Reducer – HK Old Is Gold | 45mm, 57mm \u0026 63mm","description":"\u003ch2\u003eHK Old Is Gold DB Killer \/ Sound Reducer for Royal Enfield Punjab Silencers – 45mm, 57mm \u0026amp; 63mm\u003c\/h2\u003e\n\n\u003cp\u003eIf your \u003cstrong\u003eRoyal Enfield Punjab silencer is too loud for everyday use\u003c\/strong\u003e, this HK Old Is Gold removable \u003cstrong\u003eDB killer \/ exhaust baffle \/ silencer sound reducer\u003c\/strong\u003e is designed to reduce the exhaust outlet opening and moderate the exhaust note without replacing the complete silencer.\u003c\/p\u003e\n\n\u003cp\u003eThis listing brings the three commonly sold Punjab-silencer mouth sizes into one properly explained product:\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\u003cstrong\u003e45mm – Small Mouth\u003c\/strong\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003cstrong\u003e57mm – Big Mouth\u003c\/strong\u003e\u003c\/li\u003e\n  \u003cli\u003e\u003cstrong\u003e63mm – Extra Big Mouth \/ newest largest size\u003c\/strong\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003e\u003cstrong\u003eBrand:\u003c\/strong\u003e HK Old Is Gold \/ HK\u003cbr\u003e\n\u003cstrong\u003eProduct:\u003c\/strong\u003e Removable DB Killer \/ Sound Reducer \/ Exhaust Baffle for compatible Punjab-style silencers\u003cbr\u003e\n\u003cstrong\u003eFinish:\u003c\/strong\u003e Black\u003cbr\u003e\n\u003cstrong\u003e57mm HK box reference:\u003c\/strong\u003e \u003cstrong\u003eHKDB2 – “DB KILLER PUN. (57MM)”\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eImportant:\u003c\/strong\u003e Buy by the \u003cstrong\u003eactual silencer mouth\/outlet size\u003c\/strong\u003e, not simply by motorcycle model. A Classic 350, Bullet, Electra or Reborn can be fitted with different aftermarket silencers, so the motorcycle name alone does not determine whether you need 45mm, 57mm or 63mm.\u003c\/p\u003e\n\n\u003ch3\u003eChoose the Correct Size\u003c\/h3\u003e\n\n\u003ctable\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n      \u003cth\u003eVariant\u003c\/th\u003e\n      \u003cth\u003eCommon Market Name\u003c\/th\u003e\n      \u003cth\u003eTypical Use\u003c\/th\u003e\n      \u003cth\u003eHK Reference\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003cstrong\u003e45mm\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd\u003eSmall Mouth \/ Chota Muh\u003c\/td\u003e\n      \u003ctd\u003ePunjab \/ Mini Punjab silencers with an approximately 45mm outlet designed to accept this style of insert\u003c\/td\u003e\n      \u003ctd\u003eExact HK code not verified – not guessed\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003cstrong\u003e57mm\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd\u003eBig Mouth \/ Bada Muh\u003c\/td\u003e\n      \u003ctd\u003ePunjab \/ Mini Punjab silencers with an approximately 56–57mm outlet designed to accept this style of insert\u003c\/td\u003e\n      \u003ctd\u003e\n\u003cstrong\u003eHKDB2\u003c\/strong\u003e – box marked “DB KILLER PUN. (57MM)”\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e\u003cstrong\u003e63mm\u003c\/strong\u003e\u003c\/td\u003e\n      \u003ctd\u003eExtra Big Mouth \/ 63mm Large Mouth\u003c\/td\u003e\n      \u003ctd\u003eLatest\/larger 63mm Punjab-silencer mouth format where the outlet is designed for a 63mm reducer\u003c\/td\u003e\n      \u003ctd\u003eExact HK code not verified – not guessed\u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003e45mm vs 57mm vs 63mm – What Does the Size Mean?\u003c\/h3\u003e\n\n\u003cp\u003eThe \u003cstrong\u003e45mm \/ 57mm \/ 63mm measurement refers to the rear silencer mouth \/ outlet family\u003c\/strong\u003e for which the reducer is intended. It is \u003cstrong\u003enot the motorcycle exhaust-header diameter, bend-pipe diameter or engine-port diameter\u003c\/strong\u003e.\u003c\/p\u003e\n\n\u003cp\u003eThis distinction matters because the same motorcycle can be running:\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003ea Small Mouth Punjab silencer,\u003c\/li\u003e\n  \u003cli\u003ea Big Mouth Punjab silencer,\u003c\/li\u003e\n  \u003cli\u003ea newer Extra Big Mouth 63mm silencer,\u003c\/li\u003e\n  \u003cli\u003eor an entirely different exhaust design.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eTherefore, never select the DB killer only because your motorcycle is called Classic 350, Bullet 350, Electra, Reborn or another Royal Enfield model.\u003c\/p\u003e\n\n\u003ch3\u003eHow to Measure Before Ordering\u003c\/h3\u003e\n\n\u003col\u003e\n  \u003cli\u003eAllow the exhaust to become \u003cstrong\u003ecompletely cold\u003c\/strong\u003e.\u003c\/li\u003e\n  \u003cli\u003eMeasure the \u003cstrong\u003einside opening \/ usable outlet diameter\u003c\/strong\u003e at the rear mouth of the silencer where the DB killer will sit.\u003c\/li\u003e\n  \u003cli\u003eAlso check whether your silencer has the \u003cstrong\u003eretaining-screw arrangement\u003c\/strong\u003e required for this style of removable insert.\u003c\/li\u003e\n  \u003cli\u003eCompare your measurement with the 45mm, 57mm and 63mm choices.\u003c\/li\u003e\n  \u003cli\u003eIf your measurement is between sizes or the silencer has a different internal lip\/step, do not force-fit the insert.\u003c\/li\u003e\n\u003c\/ol\u003e\n\n\u003cp\u003e\u003cstrong\u003eBest practice:\u003c\/strong\u003e if your existing silencer itself is sold as “45mm Small Mouth”, “57mm Big Mouth” or “63mm Extra Big Mouth”, choose the corresponding DB-killer size. If the exhaust brand\/model is unknown, measure it physically.\u003c\/p\u003e\n\n\u003ch3\u003eVerified Market Size Mapping\u003c\/h3\u003e\n\n\u003cp\u003eCurrent Royal Enfield exhaust specialists sell Punjab-silencer DB killers in the same \u003cstrong\u003e45mm, 57mm and 63mm\u003c\/strong\u003e size families. The 45mm size is commonly associated with the Small Mouth format, approximately 56–57mm with Big Mouth, and 63mm with the newest Extra Big Mouth format.\u003c\/p\u003e\n\n\u003cp\u003eThe exact shape, internal step and retaining point can still differ between exhaust manufacturers, so \u003cstrong\u003ematching diameter is necessary but should not be treated as the only possible fitment check\u003c\/strong\u003e.\u003c\/p\u003e\n\n\u003ch3\u003eWhat Does a DB Killer Actually Do?\u003c\/h3\u003e\n\n\u003cp\u003eA DB killer—also called a \u003cstrong\u003esound reducer, exhaust baffle, silencer insert, noise reducer or muffler insert\u003c\/strong\u003e—partially restricts the open outlet of an aftermarket exhaust. The purpose is to \u003cstrong\u003emoderate an excessively loud exhaust note\u003c\/strong\u003e and make the bike more manageable for daily riding or longer journeys.\u003c\/p\u003e\n\n\u003cp\u003eIt does \u003cstrong\u003enot\u003c\/strong\u003e turn an aftermarket exhaust into an original Royal Enfield silencer, and we do not publish a fixed “X dB reduction” because actual sound change depends on the complete exhaust system, silencer construction, engine, packing condition and installation.\u003c\/p\u003e\n\n\u003ch3\u003eWhy Buy the Correct HK-Sized Reducer Instead of a Random Universal Insert?\u003c\/h3\u003e\n\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eThree useful Punjab sizes:\u003c\/strong\u003e 45mm, 57mm and 63mm.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHK Old Is Gold branding:\u003c\/strong\u003e intended for the Royal Enfield aftermarket exhaust market rather than an unidentified generic insert.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSize-based selection:\u003c\/strong\u003e lets you match the reducer to the actual silencer mouth instead of guessing from the motorcycle model.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRemovable design:\u003c\/strong\u003e the insert is retained mechanically rather than permanently welded into the silencer.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBlack finish:\u003c\/strong\u003e visually unobtrusive inside the exhaust outlet.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eReplacement option:\u003c\/strong\u003e useful if the original removable reducer supplied with a compatible Punjab silencer has been lost or removed.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eCompatibility – Read This Before Buying\u003c\/h3\u003e\n\n\u003cp\u003eThis listing is primarily intended for \u003cstrong\u003ePunjab \/ Long Punjab \/ Mini Punjab style Royal Enfield aftermarket silencers\u003c\/strong\u003e that use the matching mouth size and retaining arrangement.\u003c\/p\u003e\n\n\u003ctable\u003e\n  \u003cthead\u003e\n    \u003ctr\u003e\n      \u003cth\u003eExhaust \/ Application\u003c\/th\u003e\n      \u003cth\u003eCompatibility Guidance\u003c\/th\u003e\n    \u003c\/tr\u003e\n  \u003c\/thead\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e45mm Small Mouth Punjab \/ Mini Punjab\u003c\/td\u003e\n      \u003ctd\u003e\n\u003cstrong\u003eChoose 45mm\u003c\/strong\u003e after confirming physical outlet size and retaining arrangement.\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e56–57mm Big Mouth Punjab \/ Mini Punjab\u003c\/td\u003e\n      \u003ctd\u003e\n\u003cstrong\u003eChoose 57mm\u003c\/strong\u003e. HK's photographed 57mm unit is code HKDB2.\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003e63mm Extra Big Mouth Punjab\u003c\/td\u003e\n      \u003ctd\u003e\n\u003cstrong\u003eChoose 63mm\u003c\/strong\u003e after confirming the silencer uses the 63mm large-mouth format.\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eHK \/ HKK Old Is Gold Punjab silencers\u003c\/td\u003e\n      \u003ctd\u003eUse the size that matches the actual HK silencer mouth. Do not select solely by bike model.\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eOther-brand Punjab-style silencers\u003c\/td\u003e\n      \u003ctd\u003e\n\u003cstrong\u003ePossible only after measurement.\u003c\/strong\u003e Diameter, internal lip and retaining screw must match.\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eIndori \/ Goldstar \/ Cobra \/ Dolphin \/ Red Rooster \/ AEW or other exhaust designs\u003c\/td\u003e\n      \u003ctd\u003e\n\u003cstrong\u003eNot automatically compatible.\u003c\/strong\u003e These exhausts can use different baffles and retention systems even when the outlet looks similar.\u003c\/td\u003e\n    \u003c\/tr\u003e\n    \u003ctr\u003e\n      \u003ctd\u003eRoyal Enfield stock \/ genuine silencer\u003c\/td\u003e\n      \u003ctd\u003e\n\u003cstrong\u003eNot claimed.\u003c\/strong\u003e This product is for compatible aftermarket silencer outlets, not a universal insert for the factory exhaust.\u003c\/td\u003e\n    \u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eMotorcycle Fitment – Why We Do Not List One Bike Model\u003c\/h3\u003e\n\n\u003cp\u003eA DB killer fits the \u003cstrong\u003esilencer\u003c\/strong\u003e, not directly the engine or motorcycle chassis. A Royal Enfield Classic 350 UCE, Classic 350 Reborn, Bullet, Electra or other model may be using different aftermarket silencers with different outlet sizes.\u003c\/p\u003e\n\n\u003cp\u003eFor example, 63mm Long Punjab exhausts are currently sold in more than one Royal Enfield fitment configuration. The DB-killer decision should therefore be made from the \u003cstrong\u003einstalled silencer's outlet specification\u003c\/strong\u003e, not from the motorcycle name alone.\u003c\/p\u003e\n\n\u003ch3\u003eWhat You Receive\u003c\/h3\u003e\n\n\u003cul\u003e\n  \u003cli\u003e1 × HK Old Is Gold DB Killer \/ Sound Reducer in the selected size\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eThe current 57mm unit shown is supplied as an HK-branded black removable insert with its retaining screw. \u003cstrong\u003eDo not assume an Allen key or any additional tool is included unless it is physically present in the supplied HK package.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003ch3\u003eInstallation Guidance\u003c\/h3\u003e\n\n\u003cul\u003e\n  \u003cli\u003eWork only when the silencer is completely cold.\u003c\/li\u003e\n  \u003cli\u003eConfirm size before insertion.\u003c\/li\u003e\n  \u003cli\u003eInsert the DB killer squarely into the compatible exhaust mouth.\u003c\/li\u003e\n  \u003cli\u003eAlign the retaining point carefully.\u003c\/li\u003e\n  \u003cli\u003eTighten the retaining screw sufficiently to prevent movement, but do not overtighten and damage threads.\u003c\/li\u003e\n  \u003cli\u003eCheck that the insert cannot rotate, rattle or move outward.\u003c\/li\u003e\n  \u003cli\u003eAfter the first ride, allow the exhaust to cool and re-check the retaining screw.\u003c\/li\u003e\n  \u003cli\u003eIf the insert needs excessive force, stop: the size or internal exhaust design is likely incorrect.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eSound \u0026amp; Performance – No False Promises\u003c\/h3\u003e\n\n\u003cp\u003eThe purpose of this product is \u003cstrong\u003esound moderation\u003c\/strong\u003e. We do not claim a fixed decibel reduction, horsepower gain, mileage increase, throttle-response improvement or engine-performance benefit.\u003c\/p\u003e\n\n\u003cp\u003eInstalling a restrictive insert can change exhaust flow and sound characteristics. The result varies with the exhaust and motorcycle setup.\u003c\/p\u003e\n\n\u003ch3\u003eRoad-Legal \/ Police-Challan Note\u003c\/h3\u003e\n\n\u003cp\u003e\u003cstrong\u003eA DB killer does not automatically make an aftermarket silencer road-legal.\u003c\/strong\u003e Road legality can depend on the exhaust itself, applicable vehicle rules, approved noise limits and the actual sound produced by the motorcycle.\u003c\/p\u003e\n\n\u003cp\u003eThis item should therefore be purchased as a \u003cstrong\u003esound-reduction accessory\u003c\/strong\u003e, not as a guarantee against traffic enforcement, challans, inspection failure or noise-limit violations.\u003c\/p\u003e\n\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\n\u003ch4\u003eWhich DB killer should I buy for a Small Mouth Punjab silencer?\u003c\/h4\u003e\n\u003cp\u003eIf the silencer outlet is the common \u003cstrong\u003e45mm Small Mouth\u003c\/strong\u003e format and the retaining arrangement matches, select \u003cstrong\u003e45mm\u003c\/strong\u003e.\u003c\/p\u003e\n\n\u003ch4\u003eWhich size is for a Big Mouth Punjab silencer?\u003c\/h4\u003e\n\u003cp\u003eThe established Big Mouth family is commonly around \u003cstrong\u003e56–57mm\u003c\/strong\u003e. Select the \u003cstrong\u003e57mm\u003c\/strong\u003e variant after measurement. The photographed HK 57mm package is marked \u003cstrong\u003eHKDB2 – DB KILLER PUN. (57MM)\u003c\/strong\u003e.\u003c\/p\u003e\n\n\u003ch4\u003eWhat is the 63mm version?\u003c\/h4\u003e\n\u003cp\u003eThe \u003cstrong\u003e63mm\u003c\/strong\u003e option is the newest\/largest mouth size in this three-size Punjab-silencer range and is intended for compatible \u003cstrong\u003e63mm Extra Big Mouth\u003c\/strong\u003e exhaust outlets.\u003c\/p\u003e\n\n\u003ch4\u003eWill 63mm fit every latest Royal Enfield?\u003c\/h4\u003e\n\u003cp\u003e\u003cstrong\u003eNo.\u003c\/strong\u003e The 63mm number describes the silencer outlet family, not the motorcycle generation. Your bike must actually be fitted with a compatible 63mm-mouth exhaust.\u003c\/p\u003e\n\n\u003ch4\u003eWill this fit my Classic 350 Reborn?\u003c\/h4\u003e\n\u003cp\u003eIt depends entirely on the \u003cstrong\u003eaftermarket silencer fitted to the motorcycle\u003c\/strong\u003e. If that silencer uses a compatible 45mm, 57mm or 63mm Punjab-style outlet and retention system, choose the matching size. Do not order only from the bike name.\u003c\/p\u003e\n\n\u003ch4\u003eWill this fit Bullet \/ Electra \/ Classic UCE?\u003c\/h4\u003e\n\u003cp\u003eThe same principle applies: identify the aftermarket silencer and measure its mouth. The motorcycle model by itself is not enough to identify the correct DB-killer diameter.\u003c\/p\u003e\n\n\u003ch4\u003eCan I use it on a non-HK silencer?\u003c\/h4\u003e\n\u003cp\u003ePossibly, but only if the \u003cstrong\u003ephysical diameter, internal seating area and screw\/retaining arrangement match\u003c\/strong\u003e. No blanket universal-fit claim is made for other exhaust brands.\u003c\/p\u003e\n\n\u003ch4\u003eDoes the DB killer make the exhaust silent like stock?\u003c\/h4\u003e\n\u003cp\u003eNot necessarily. It is designed to \u003cstrong\u003ereduce\/moderate\u003c\/strong\u003e sound. The final exhaust note depends on the complete silencer and motorcycle setup.\u003c\/p\u003e\n\n\u003ch4\u003eHow many dB will it reduce?\u003c\/h4\u003e\n\u003cp\u003eNo verified fixed reduction figure is available for these HK inserts across every exhaust configuration, so we do not publish an invented decibel claim.\u003c\/p\u003e\n\n\u003ch4\u003eDoes it improve mileage or power?\u003c\/h4\u003e\n\u003cp\u003eNo mileage, horsepower or performance improvement is promised. This listing is for a \u003cstrong\u003esound-reduction insert\u003c\/strong\u003e.\u003c\/p\u003e\n\n\u003ch4\u003eWill fitting this stop police challans?\u003c\/h4\u003e\n\u003cp\u003e\u003cstrong\u003eNo guarantee can be made.\u003c\/strong\u003e The legality of an aftermarket exhaust depends on applicable regulations and the complete exhaust\/noise setup. A DB killer can reduce sound but does not certify the exhaust as road legal.\u003c\/p\u003e\n\n\u003ch4\u003eWhat if I am not sure between 57mm and 63mm?\u003c\/h4\u003e\n\u003cp\u003eMeasure the actual rear mouth\/outlet of the silencer before ordering. Do not force the larger or smaller insert into the wrong exhaust.\u003c\/p\u003e\n\n\u003ch3\u003eSize Summary\u003c\/h3\u003e\n\n\u003cp\u003e\u003cstrong\u003e45mm = Small Mouth\u003c\/strong\u003e\u003cbr\u003e\n\u003cstrong\u003e57mm = Big Mouth\u003c\/strong\u003e\u003cbr\u003e\n\u003cstrong\u003e63mm = Extra Big Mouth \/ newest largest option\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eFor the lowest chance of a wrong order, \u003cstrong\u003emeasure first, then select the size\u003c\/strong\u003e.\u003c\/p\u003e","brand":"HK Old Is Gold","offers":[{"title":"45mm – Small Mouth","offer_id":52205281706279,"sku":null,"price":490.0,"currency_code":"INR","in_stock":true},{"title":"57mm – Big Mouth","offer_id":52205281739047,"sku":"HKDB2","price":490.0,"currency_code":"INR","in_stock":true},{"title":"63mm – Extra Big Mouth","offer_id":52205281771815,"sku":null,"price":0.0,"currency_code":"INR","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0878\/7447\/0183\/files\/0030F16B-DA71-4364-B09F-82BEA5367956.jpg?v=1790918464","url":"https:\/\/underthehood.co.in\/products\/hk-old-is-gold-db-killer-punjab-silencer-45-57-63mm","provider":"UNDER THE HOOD","version":"1.0","type":"link"}