{"product_id":"royal-enfield-143766b-rotor-assembly-12v-acdc-bullet-350-500-lightning-535","title":"Royal Enfield 143766\/B – Rotor Assembly 12V AC\/DC (Alternator Rotor Magnet) for Bullet 350\/500, Lightning 500\/535, Machismo A350, Campus, Standard 350","description":"\u003cp data-start=\"320\" data-end=\"756\"\u003eRoyal Enfield \u003cstrong data-start=\"334\" data-end=\"346\"\u003e143766\/B\u003c\/strong\u003e is the genuine \u003cstrong data-start=\"362\" data-end=\"388\"\u003eROTOR ASSY – 12V AC\/DC\u003c\/strong\u003e used in the alternator of classic cast-iron and early AVL Bullets. The official Royal Enfield parts list describes base part \u003cstrong data-start=\"514\" data-end=\"524\"\u003e143766\u003c\/strong\u003e as \u003cstrong data-start=\"528\" data-end=\"563\"\u003e“ROTOR ASSEMBLY 12V AC\/DC 350C”\u003c\/strong\u003e, confirming it is the 12-volt AC\/DC alternator rotor for 350cc platforms. EU genuine-parts portals and price lists list \u003cstrong data-start=\"686\" data-end=\"711\"\u003e143766\/B – ROTOR ASSY\u003c\/strong\u003e as the current revision of the same part.\u003c\/p\u003e\n\u003cp data-start=\"758\" data-end=\"1225\"\u003e\u003cstrong data-start=\"814\" data-end=\"840\"\u003e143766B rotor assembly\u003c\/strong\u003e specifically for \u003cstrong data-start=\"858\" data-end=\"983\"\u003eCampus (1997–1999), Lightning 500 (2001–2002), Lightning 535 (2001–2002), Machismo A350 (1999–2005), Standard 350 (1995–)\u003c\/strong\u003e. The Spares Company and other international sellers list the same rotor under \u003cstrong data-start=\"1064\" data-end=\"1179\"\u003eBullet 350, Deluxe, Machismo, Campus, Bullet 500 (2000), Lightning-500 (2000), Lightning-535 \/ Lightning-535 ES\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp data-start=\"1227\" data-end=\"1687\"\u003eFunctionally, this is the \u003cstrong data-start=\"1253\" data-end=\"1291\"\u003ealternator rotor magnet + reluctor\u003c\/strong\u003e that works with the 12V stator and AC\/DC system to generate charging current and provide timing signals. A worn, damaged or de-magnetised rotor can cause \u003cstrong data-start=\"1446\" data-end=\"1515\"\u003eweak charging, battery drain, flickering lights or misfire issues\u003c\/strong\u003e. Replacing it with an OEM \u003cstrong data-start=\"1542\" data-end=\"1554\"\u003e143766\/B\u003c\/strong\u003e restores proper alternator output and ignition timing, avoiding hit-or-miss results from local rewinding jobs or universal rotors.\u003c\/p\u003e\n\u003cblockquote data-start=\"1689\" data-end=\"1865\"\u003e\n\u003cp data-start=\"1691\" data-end=\"1865\"\u003e⚠️ \u003cstrong data-start=\"1694\" data-end=\"1708\"\u003eImportant:\u003c\/strong\u003e This rotor is for \u003cstrong data-start=\"1727\" data-end=\"1801\"\u003eolder 12V AC\/DC Bullets, Lightning, Machismo, Campus, Standard 350\/500\u003c\/strong\u003e. It is \u003cstrong data-start=\"1809\" data-end=\"1816\"\u003enot\u003c\/strong\u003e for UCE, J-Series, Himalayan, 450s or 650 Twins.\u003c\/p\u003e\n\u003c\/blockquote\u003e\n\u003chr data-start=\"1867\" data-end=\"1870\"\u003e\n\u003ch3 data-start=\"1872\" data-end=\"1903\"\u003eKey Features \u003c\/h3\u003e\n\u003cul data-start=\"1905\" data-end=\"3137\"\u003e\n\u003cli data-start=\"1905\" data-end=\"2058\"\u003e\n\u003cp data-start=\"1907\" data-end=\"2058\"\u003e\u003cstrong data-start=\"1907\" data-end=\"1947\"\u003eGenuine Royal Enfield rotor assembly\u003c\/strong\u003e – Part \u003cstrong data-start=\"1955\" data-end=\"1967\"\u003e143766\/B\u003c\/strong\u003e, revision of \u003cstrong data-start=\"1981\" data-end=\"2025\"\u003e143766 – “ROTOR ASSEMBLY 12V AC\/DC 350C”\u003c\/strong\u003e from the factory master list.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"2059\" data-end=\"2204\"\u003e\n\u003cp data-start=\"2061\" data-end=\"2204\"\u003eDesigned for \u003cstrong data-start=\"2074\" data-end=\"2106\"\u003e12V AC\/DC alternator systems\u003c\/strong\u003e on classic Bullet \/ Lightning \/ Machismo platforms – works with matching stator and regulator.\u003cbr\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"2373\" data-end=\"2543\"\u003e\n\u003cp data-start=\"2375\" data-end=\"2543\"\u003eConfirmed fitment for \u003cstrong data-start=\"2397\" data-end=\"2455\"\u003eCampus, Lightning 500\/535, Machismo A350, Standard 350\u003c\/strong\u003e and \u003cstrong data-start=\"2460\" data-end=\"2504\"\u003eBullet 350\/500, Deluxe, Lightning-535 ES\u003c\/strong\u003e via “Fits in these models” mapping.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"2544\" data-end=\"2704\"\u003e\n\u003cp data-start=\"2546\" data-end=\"2704\"\u003eMaintains correct \u003cstrong data-start=\"2564\" data-end=\"2603\"\u003echarging output and ignition signal\u003c\/strong\u003e; a weak rotor is a common hidden cause of \u003cstrong data-start=\"2646\" data-end=\"2682\"\u003elow charging and random misfires\u003c\/strong\u003e on CI\/AVL Bullets.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"2705\" data-end=\"2848\"\u003e\n\u003cp data-start=\"2707\" data-end=\"2848\"\u003eOEM machining and magnet strength for \u003cstrong data-start=\"2745\" data-end=\"2783\"\u003estable output at idle and high RPM\u003c\/strong\u003e, unlike some aftermarket rotors which lose magnetism quickly.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"2849\" data-end=\"2983\"\u003e\n\u003cp data-start=\"2851\" data-end=\"2983\"\u003eSupplied as a \u003cstrong data-start=\"2865\" data-end=\"2892\"\u003ecomplete rotor assembly\u003c\/strong\u003e – ready to mount on the crankshaft with the correct taper and keyway for these engines.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"2984\" data-end=\"3137\"\u003e\n\u003cp data-start=\"2986\" data-end=\"3137\"\u003eBacked by official \u003cstrong data-start=\"3005\" data-end=\"3061\"\u003eRoyal Enfield price lists \/ retired model catalogues\u003c\/strong\u003e showing 143766\/B as the correct rotor assembly for these earlier models.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr data-start=\"3139\" data-end=\"3142\"\u003e\n\u003ch3 data-start=\"3144\" data-end=\"3169\"\u003eCompatibility Table\u003c\/h3\u003e\n\u003ch4 data-start=\"3171\" data-end=\"3220\"\u003e✅ Confirmed Fitment \u003c\/h4\u003e\n\u003cdiv class=\"_tableContainer_1rjym_1\"\u003e\n\u003cdiv class=\"group _tableWrapper_1rjym_13 flex w-fit flex-col-reverse\" tabindex=\"-1\"\u003e\n\u003ctable data-start=\"3222\" data-end=\"5309\" class=\"w-fit min-w-(--thread-content-width)\"\u003e\n\u003cthead data-start=\"3222\" data-end=\"3341\"\u003e\n\u003ctr data-start=\"3222\" data-end=\"3341\"\u003e\n\u003cth data-start=\"3222\" data-end=\"3246\" data-col-size=\"sm\"\u003eModel \/ Family\u003c\/th\u003e\n\u003cth data-start=\"3246\" data-end=\"3278\" data-col-size=\"sm\"\u003eEngine \/ Platform\u003c\/th\u003e\n\u003cth data-start=\"3278\" data-end=\"3299\" data-col-size=\"sm\"\u003eElectrical Type\u003c\/th\u003e\n\u003cth data-start=\"3299\" data-end=\"3321\" data-col-size=\"sm\"\u003eApprox. Years*\u003c\/th\u003e\n\u003cth data-start=\"3321\" data-end=\"3341\" data-col-size=\"xl\"\u003eEvidence \u0026amp; Notes\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody data-start=\"3462\" data-end=\"5309\"\u003e\n\u003ctr data-start=\"3462\" data-end=\"3715\"\u003e\n\u003ctd data-start=\"3462\" data-end=\"3486\" data-col-size=\"sm\"\u003eStandard 350 (CI)\u003c\/td\u003e\n\u003ctd data-start=\"3486\" data-end=\"3518\" data-col-size=\"sm\"\u003e346cc Cast-Iron (CI)\u003c\/td\u003e\n\u003ctd data-start=\"3518\" data-end=\"3541\" data-col-size=\"sm\"\u003e12V AC\/DC alternator\u003c\/td\u003e\n\u003ctd data-start=\"3541\" data-end=\"3564\" data-col-size=\"sm\"\u003e~1995–onwards CI run\u003c\/td\u003e\n\u003ctd data-start=\"3564\" data-end=\"3715\" data-col-size=\"xl\"\u003e\u003cbr\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr data-start=\"3716\" data-end=\"3933\"\u003e\n\u003ctd data-start=\"3716\" data-end=\"3740\" data-col-size=\"sm\"\u003eCampus\u003c\/td\u003e\n\u003ctd data-start=\"3740\" data-end=\"3772\" data-col-size=\"sm\"\u003e346cc CI\u003c\/td\u003e\n\u003ctd data-start=\"3772\" data-end=\"3793\" data-col-size=\"sm\"\u003e12V AC\/DC\u003c\/td\u003e\n\u003ctd data-start=\"3793\" data-end=\"3815\" data-col-size=\"sm\"\u003e1997–1999\u003c\/td\u003e\n\u003ctd data-start=\"3815\" data-end=\"3933\" data-col-size=\"xl\"\u003e\u003cbr\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr data-start=\"3934\" data-end=\"4182\"\u003e\n\u003ctd data-start=\"3934\" data-end=\"3958\" data-col-size=\"sm\"\u003eLightning 500\u003c\/td\u003e\n\u003ctd data-start=\"3958\" data-end=\"3990\" data-col-size=\"sm\"\u003e499cc CI\u003c\/td\u003e\n\u003ctd data-start=\"3990\" data-end=\"4011\" data-col-size=\"sm\"\u003e12V AC\/DC\u003c\/td\u003e\n\u003ctd data-start=\"4011\" data-end=\"4033\" data-col-size=\"sm\"\u003e2000–2002\u003c\/td\u003e\n\u003ctd data-start=\"4033\" data-end=\"4182\" data-col-size=\"xl\"\u003e\u003cbr\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr data-start=\"4183\" data-end=\"4417\"\u003e\n\u003ctd data-start=\"4183\" data-end=\"4207\" data-col-size=\"sm\"\u003eLightning 535 \/ ES\u003c\/td\u003e\n\u003ctd data-start=\"4207\" data-end=\"4239\" data-col-size=\"sm\"\u003e535cc CI \/ AVL (early)\u003c\/td\u003e\n\u003ctd data-start=\"4239\" data-end=\"4260\" data-col-size=\"sm\"\u003e12V AC\/DC\u003c\/td\u003e\n\u003ctd data-start=\"4260\" data-end=\"4282\" data-col-size=\"sm\"\u003e2001–2002\u003c\/td\u003e\n\u003ctd data-start=\"4282\" data-end=\"4417\" data-col-size=\"xl\"\u003e\u003cbr\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr data-start=\"4418\" data-end=\"4628\"\u003e\n\u003ctd data-start=\"4418\" data-end=\"4442\" data-col-size=\"sm\"\u003eMachismo A350\u003c\/td\u003e\n\u003ctd data-start=\"4442\" data-end=\"4474\" data-col-size=\"sm\"\u003e346cc AVL\/CI variant\u003c\/td\u003e\n\u003ctd data-start=\"4474\" data-end=\"4495\" data-col-size=\"sm\"\u003e12V AC\/DC\u003c\/td\u003e\n\u003ctd data-start=\"4495\" data-end=\"4517\" data-col-size=\"sm\"\u003e1999–2005\u003c\/td\u003e\n\u003ctd data-start=\"4517\" data-end=\"4628\" data-col-size=\"xl\"\u003e\u003cbr\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr data-start=\"4629\" data-end=\"4911\"\u003e\n\u003ctd data-start=\"4629\" data-end=\"4653\" data-col-size=\"sm\"\u003eBullet 350 (CI 12V)\u003c\/td\u003e\n\u003ctd data-start=\"4653\" data-end=\"4685\" data-col-size=\"sm\"\u003e346cc Cast-Iron\u003c\/td\u003e\n\u003ctd data-start=\"4685\" data-end=\"4706\" data-col-size=\"sm\"\u003e12V AC\/DC\u003c\/td\u003e\n\u003ctd data-start=\"4706\" data-end=\"4728\" data-col-size=\"sm\"\u003eLate 1990s–2000s\u003c\/td\u003e\n\u003ctd data-start=\"4728\" data-end=\"4911\" data-col-size=\"xl\"\u003e\u003cbr\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr data-start=\"4912\" data-end=\"5085\"\u003e\n\u003ctd data-start=\"4912\" data-end=\"4936\" data-col-size=\"sm\"\u003eDeluxe (CI)\u003c\/td\u003e\n\u003ctd data-start=\"4936\" data-end=\"4968\" data-col-size=\"sm\"\u003e346cc CI\u003c\/td\u003e\n\u003ctd data-start=\"4968\" data-end=\"4989\" data-col-size=\"sm\"\u003e12V AC\/DC\u003c\/td\u003e\n\u003ctd data-start=\"4989\" data-end=\"5011\" data-col-size=\"sm\"\u003eMid-1980s onwards\u003c\/td\u003e\n\u003ctd data-start=\"5011\" data-end=\"5085\" data-col-size=\"xl\"\u003e\u003cbr\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr data-start=\"5086\" data-end=\"5309\"\u003e\n\u003ctd data-start=\"5086\" data-end=\"5110\" data-col-size=\"sm\"\u003eBullet 500 (CI)\u003c\/td\u003e\n\u003ctd data-start=\"5110\" data-end=\"5141\" data-col-size=\"sm\"\u003e499cc Cast-Iron\u003c\/td\u003e\n\u003ctd data-start=\"5141\" data-end=\"5162\" data-col-size=\"sm\"\u003e12V AC\/DC\u003c\/td\u003e\n\u003ctd data-start=\"5162\" data-end=\"5184\" data-col-size=\"sm\"\u003e~2000+\u003c\/td\u003e\n\u003ctd data-start=\"5184\" data-end=\"5309\" data-col-size=\"xl\"\u003e\u003cbr\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cp data-start=\"5311\" data-end=\"5434\"\u003e\u003cspan style=\"color: rgb(255, 30, 30);\"\u003e\u003cstrong\u003ePLEASE CHECK PART NUMBER BEFORE PURCHASE \u003c\/strong\u003e\u003c\/span\u003e\u003c\/p\u003e\n\u003chr data-start=\"5859\" data-end=\"5862\"\u003e\n\u003ch3 data-start=\"5864\" data-end=\"5876\"\u003eVariants\u003c\/h3\u003e\n\u003cp data-start=\"5878\" data-end=\"5901\"\u003eSingle OEM design only:\u003c\/p\u003e\n\u003cul data-start=\"5903\" data-end=\"6084\"\u003e\n\u003cli data-start=\"5903\" data-end=\"5952\"\u003e\n\u003cp data-start=\"5905\" data-end=\"5952\"\u003e\u003cstrong data-start=\"5905\" data-end=\"5914\"\u003ePart:\u003c\/strong\u003e 143766\/B – Rotor Assembly 12V AC\/DC\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"5953\" data-end=\"6084\"\u003e\n\u003cp data-start=\"5955\" data-end=\"6084\"\u003e\u003cstrong data-start=\"5955\" data-end=\"5971\"\u003eSupplied as:\u003c\/strong\u003e 1N rotor assembly (rotor + reluctor ring as per OEM; nut and key sold separately under their own part numbers)\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp data-start=\"6086\" data-end=\"6123\"\u003eOn Shopify you can optionally create:\u003c\/p\u003e\n\u003cul data-start=\"6125\" data-end=\"6316\"\u003e\n\u003cli data-start=\"6125\" data-end=\"6181\"\u003e\n\u003cp data-start=\"6127\" data-end=\"6181\"\u003e\u003cstrong data-start=\"6127\" data-end=\"6160\"\u003eVariant 1 – Single Rotor (1N)\u003c\/strong\u003e – default purchase\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli data-start=\"6182\" data-end=\"6316\"\u003e\n\u003cp data-start=\"6184\" data-end=\"6316\"\u003e\u003cstrong data-start=\"6184\" data-end=\"6246\"\u003eVariant 2 – Combo with Rotor Nut (1N rotor + nut 140317-1)\u003c\/strong\u003e as an upsell bundle, since dealers frequently list these together.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr data-start=\"6318\" data-end=\"6321\"\u003e\n\u003ch3 data-start=\"6323\" data-end=\"6337\"\u003eFAQs \u003c\/h3\u003e\n\u003cp data-start=\"6339\" data-end=\"6707\"\u003e\u003cstrong data-start=\"6339\" data-end=\"6411\"\u003eQ1. What does the Royal Enfield 143766\/B rotor assembly actually do?\u003c\/strong\u003e\u003cbr data-start=\"6411\" data-end=\"6414\"\u003eIt is the \u003cstrong data-start=\"6424\" data-end=\"6462\"\u003ealternator rotor magnet \/ reluctor\u003c\/strong\u003e in the 12V AC\/DC charging system. It spins with the crankshaft inside the stator, generating current for the battery and lights, and providing timing pulses for ignition on these older Bullets. A bad rotor = weak charging and unstable spark.\u003c\/p\u003e\n\u003chr data-start=\"6709\" data-end=\"6712\"\u003e\n\u003cp data-start=\"6714\" data-end=\"7114\"\u003e\u003cstrong data-start=\"6714\" data-end=\"6774\"\u003eQ2. How do I confirm if 143766\/B is correct for my bike?\u003c\/strong\u003e\u003cbr data-start=\"6774\" data-end=\"6777\"\u003eCheck your \u003cstrong data-start=\"6788\" data-end=\"6830\"\u003eRoyal Enfield parts book or microfiche\u003c\/strong\u003e. If it lists \u003cstrong data-start=\"6844\" data-end=\"6893\"\u003e143766 or 143766\/B – ROTOR ASSEMBLY 12V AC\/DC\u003c\/strong\u003e in the alternator section, this is the correct part. You can also match against dealer catalogues for Campus, Lightning 500\/535, Machismo A350, Standard 350, Bullet 350\/500 and Deluxe models using 12V AC\/DC electrics.\u003c\/p\u003e\n\u003chr data-start=\"7116\" data-end=\"7119\"\u003e\n\u003cp data-start=\"7121\" data-end=\"7504\"\u003e\u003cstrong data-start=\"7121\" data-end=\"7181\"\u003eQ3. Can I use this rotor on UCE or new J-Series Bullets?\u003c\/strong\u003e\u003cbr data-start=\"7181\" data-end=\"7184\"\u003eNo. UCE and J-Series engines use \u003cstrong data-start=\"7217\" data-end=\"7260\"\u003edifferent alternators and rotor designs\u003c\/strong\u003e. Their charging systems are typically full-DC with multi-phase stators and separate RR units. Fitting 143766\/B there is incorrect and can damage the charging system. Always use the exact rotor part number specified for your engine platform.\u003c\/p\u003e\n\u003chr data-start=\"7506\" data-end=\"7509\"\u003e\n\u003cp data-start=\"7511\" data-end=\"7931\"\u003e\u003cstrong data-start=\"7511\" data-end=\"7568\"\u003eQ4. What symptoms suggest my rotor needs replacement?\u003c\/strong\u003e\u003cbr data-start=\"7568\" data-end=\"7571\"\u003eCommon signs are: \u003cstrong data-start=\"7589\" data-end=\"7613\"\u003ebattery not charging\u003c\/strong\u003e, dim or flickering headlamp even with a good RR and stator, misfires at higher RPM, or a rotor that has been physically damaged (chipped reluctor teeth, cracked magnets, loose hub). In such cases, replacing the rotor assembly with a genuine \u003cstrong data-start=\"7855\" data-end=\"7867\"\u003e143766\/B\u003c\/strong\u003e is the right fix instead of repeated stator\/rectifier swaps.\u003c\/p\u003e\n\u003chr data-start=\"7933\" data-end=\"7936\"\u003e\n\u003cp data-start=\"7938\" data-end=\"8259\"\u003e\u003cstrong data-start=\"7938\" data-end=\"7983\"\u003eQ5. Is this a direct bolt-on replacement?\u003c\/strong\u003e\u003cbr data-start=\"7983\" data-end=\"7986\"\u003eYes – for the confirmed models. 143766\/B uses the \u003cstrong data-start=\"8036\" data-end=\"8072\"\u003ecorrect taper, keyway and offset\u003c\/strong\u003e for CI\/AVL 12V AC\/DC engines. You simply remove the old rotor with a proper puller tool, clean the crankshaft taper, install the new rotor, align key, and torque the rotor nut to spec.\u003c\/p\u003e","brand":"UNDER THE HOOD","offers":[{"title":"Default Title","offer_id":50771094405415,"sku":null,"price":1510.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0878\/7447\/0183\/files\/ChatGPTImageDec2_2025_10_22_57PM_69cdef3e-f4ce-43ac-b6b5-01506d0beba4.png?v=1764701758","url":"https:\/\/underthehood.co.in\/products\/royal-enfield-143766b-rotor-assembly-12v-acdc-bullet-350-500-lightning-535","provider":"UNDER THE HOOD","version":"1.0","type":"link"}