{"product_id":"compufire-40a-3-phase-charging-system-40-amp-vented-rotor-1981-1999-bt-139-10021","title":"Compufire 40A 3 Phase Charging System - 40 AMP Vented Rotor `1981-1999 BT — Harley-Davidson (1981-1999)","description":"\u003cp\u003eCompufire 40A 3-phase charging system with vented rotor for 1981–1999 Harley-Davidson Big Twin models. Produces 25 amps at idle and peaks at 40 amps above 2,800 rpm, with a vented rotor design that dissipates heat and keeps the stator running cooler for sustained high output.\u003c\/p\u003e\n\u003ch2\u003eFeatures\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e25 AMP output at idle, 40 AMP above 2800 rpm\u003c\/li\u003e\n  \u003cli\u003eVented rotor for improved heat dissipation\u003c\/li\u003e\n  \u003cli\u003eHigh-output voltage regulator at 14.25 V from idle\u003c\/li\u003e\n  \u003cli\u003eFits Softail, Dyna, and FLT with OEM primary due to narrow rotor and stator profile\u003c\/li\u003e\n  \u003cli\u003eMade in the USA\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Compufire\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer Part #:\u003c\/strong\u003e 55560\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eUPC:\u003c\/strong\u003e 694342548056\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eLength:\u003c\/strong\u003e 9 in\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWidth:\u003c\/strong\u003e 8 in\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHeight:\u003c\/strong\u003e 8 in\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 11 lbs\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eFitment\u003c\/h2\u003e\n\u003cp\u003eFits Harley-Davidson Softail, Dyna, and FLT models from 1981 to 1999 equipped with OEM primary. The narrow rotor and stator profile are designed for direct compatibility with stock primary cases.\u003c\/p\u003e\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003ch3\u003eWhat amp output does this system produce?\u003c\/h3\u003e\n\u003cp\u003e25 amps at idle and 40 amps above 2,800 rpm. This higher output keeps your battery charged during highway riding and accessories use.\u003c\/p\u003e\n\u003ch3\u003eWill this fit my 2000+ Harley Big Twin?\u003c\/h3\u003e\n\u003cp\u003eNo — this system is designed for 1981-1999 models. Newer Big Twins require updated charging systems.\u003c\/p\u003e\n\u003ch3\u003eCan I use this with an aftermarket primary?\u003c\/h3\u003e\n\u003cp\u003eThis system is designed for OEM primary cases due to the narrow rotor and stator profile. Verify fitment before ordering if you have a non-stock primary.\u003c\/p\u003e\n\u003ch3\u003eHow does the vented rotor help performance?\u003c\/h3\u003e\n\u003cp\u003eThe vented rotor design dissipates heat more efficiently, keeping the stator cooler and allowing the system to maintain maximum output for longer periods.\u003c\/p\u003e","brand":"Compufire","offers":[{"title":"Default Title","offer_id":53035872223343,"sku":"139-10021","price":613.95,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0608\/6734\/6543\/files\/6c98-5dea7fc75d4c8.jpg?v=1777529917","url":"https:\/\/vtwinbikers.com\/products\/compufire-40a-3-phase-charging-system-40-amp-vented-rotor-1981-1999-bt-139-10021","provider":"Vtwinbikers","version":"1.0","type":"link"}