{"product_id":"yoshimura-sound-insert-kit-rs-4-muffler-1-500-ring-ins-21-k","title":"Yoshimura SOUND INSERT KIT RS-4 Muffler, 1.500\" RING (INS-21-K)","description":"\u003cdiv class=\"trd trd--yoshimura\"\u003e\n\u003csection class=\"trd-hero\"\u003e\u003cp class=\"trd-eyebrow\"\u003eYoshimura · RS-4\u003c\/p\u003e\n\u003ch2 class=\"trd-headline\"\u003eLow-Volume Insert Kit for Yoshimura RS-4\u003c\/h2\u003e\n\u003cp class=\"trd-lead\"\u003eThe Yoshimura SOUND INSERT KIT RS-4 Muffler, 1.500\" RING (INS-21-K) is a replacement low-volume insert kit designed for RS-4 mufflers. Built as a Replacement Service Parts offering, it provides an optional way to tailor exhaust sound restrictions on applications that require a different sound level.\u003c\/p\u003e\n\u003cp class=\"trd-lead\"\u003eThis kit is non-spark arrested, and the amount of decibel reduction depends on the specific application. For correct application matching, refer to the insert chart and the specifications shown on the page.\u003c\/p\u003e\n\u003cul class=\"trd-chips\"\u003e\n\u003cli class=\"trd-chip\"\u003e\n\u003cspan class=\"trd-chip-label\"\u003ePart Number\u003c\/span\u003e\u003cspan class=\"trd-chip-value\"\u003eINS-21-K\u003c\/span\u003e\n\u003c\/li\u003e\n\u003cli class=\"trd-chip\"\u003e\n\u003cspan class=\"trd-chip-label\"\u003eSeries\u003c\/span\u003e\u003cspan class=\"trd-chip-value\"\u003eRS-4\u003c\/span\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\u003c\/section\u003e\u003cdiv class=\"trd-cards trd-cards--3\"\u003e\n\u003carticle class=\"trd-card\"\u003e\u003cdiv class=\"trd-card-body\"\u003e\n\u003ch3 class=\"trd-card-title\"\u003eRS-4 Muffler Insert\u003c\/h3\u003e\n\u003cp class=\"trd-card-text\"\u003eDesigned as a replacement low-volume insert kit for Yoshimura RS-4 mufflers, INS-21-K supports riders who need an insert solution for service or maintenance. It is also offered as an optional kit on applications that call for different sound restrictions.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/article\u003e\u003carticle class=\"trd-card\"\u003e\u003cdiv class=\"trd-card-body\"\u003e\n\u003ch3 class=\"trd-card-title\"\u003eNon-Spark Arrested\u003c\/h3\u003e\n\u003cp class=\"trd-card-text\"\u003eINS-21-K is specified as non-spark arrested. This detail is important when choosing components for a particular riding area or requirement, and it helps ensure the correct insert style is selected for the intended use.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/article\u003e\u003carticle class=\"trd-card\"\u003e\u003cdiv class=\"trd-card-body\"\u003e\n\u003ch3 class=\"trd-card-title\"\u003eComplete Insert Hardware\u003c\/h3\u003e\n\u003cp class=\"trd-card-text\"\u003eThe kit includes the low-volume insert tube, an end-cap collar, and a set screw. These components are intended to work together as the insert assembly for RS-4 mufflers, helping restore or configure the muffler insert arrangement as needed.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/article\u003e\n\u003c\/div\u003e\n\u003csection class=\"trd-story\"\u003e\u003cfigure class=\"trd-story-media\"\u003e\u003cimg class=\"trd-story-img\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0585\/4884\/6743\/files\/yoshimura-ins-21-k-rs4-main.jpg?v=1792280369\u0026amp;width=1400\" alt='Yoshimura SOUND INSERT KIT RS-4 Muffler, 1.500\" RING (INS-21-K) – Purpose-Built RS-4 Service Part' width=\"1400\" height=\"933\" loading=\"lazy\"\u003e\u003c\/figure\u003e\u003cdiv class=\"trd-story-copy\"\u003e\n\u003cp class=\"trd-label\"\u003eSound\u003c\/p\u003e\n\u003ch3 class=\"trd-story-title\"\u003ePurpose-Built RS-4 Service Part\u003c\/h3\u003e\n\u003cp class=\"trd-story-text\"\u003eAs part of Yoshimura’s Replacement Service Parts line for the RS-4 series, INS-21-K is intended specifically as a low-volume insert kit for RS-4 mufflers. It can be used as a replacement insert solution and is also available as an optional kit on applications that require different sound restrictions, keeping the insert choice aligned with the needs of the application.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e\u003csection class=\"trd-story trd-story--text\"\u003e\u003cdiv class=\"trd-story-copy\"\u003e\n\u003cp class=\"trd-label\"\u003eFitment\u003c\/p\u003e\n\u003ch3 class=\"trd-story-title\"\u003eSound Level Considerations\u003c\/h3\u003e\n\u003cp class=\"trd-story-text\"\u003eYoshimura notes that this is a low-volume insert kit and that decibel reduction depends on the application. Because sound results vary, the insert chart should be used to confirm correct fitment for the intended setup before installation. This helps ensure the correct insert style and configuration are selected for the muffler and application requirements.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e\u003csection class=\"trd-story trd-story--text\"\u003e\u003cdiv class=\"trd-story-copy\"\u003e\n\u003cp class=\"trd-label\"\u003eIncluded\u003c\/p\u003e\n\u003ch3 class=\"trd-story-title\"\u003eWhat’s Included and Setup\u003c\/h3\u003e\n\u003cp class=\"trd-story-text\"\u003eINS-21-K consists of the low-volume insert tube, end-cap collar, and set screw. An installation PDF is provided on the page to support proper setup. For riders working with multiple configurations, the insert chart is the recommended reference to verify the correct match for the specific application.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e\u003csection class=\"trd-section trd-section--specs\"\u003e\u003ch2 class=\"trd-section-title\"\u003eSpecifications\u003c\/h2\u003e\n\u003cdiv class=\"trd-table-wrap\"\u003e\u003ctable class=\"trd-table trd-table--specs\"\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003ePart Number\u003c\/th\u003e\n\u003ctd\u003eINS-21-K\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eBrand\u003c\/th\u003e\n\u003ctd\u003eYoshimura\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eProduct Line\u003c\/th\u003e\n\u003ctd\u003eReplacement Service Parts\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eSeries\u003c\/th\u003e\n\u003ctd\u003eRS-4\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eShipping Weight\u003c\/th\u003e\n\u003ctd\u003e0.4 lb\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth scope=\"row\"\u003eBarcode\u003c\/th\u003e\n\u003ctd\u003e00840025908772\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\u003c\/div\u003e\u003c\/section\u003e\u003csection class=\"trd-section trd-section--docs\"\u003e\u003ch2 class=\"trd-section-title\"\u003eInstallation \u0026amp; Documents\u003c\/h2\u003e\n\u003cp class=\"trd-docs\"\u003e\u003ca class=\"trd-button\" href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0585\/4884\/6743\/files\/yoshimura-ins-21-k-installation-manual.pdf?v=1792280365\" target=\"_blank\" rel=\"noopener\"\u003eInstructions \/ What's Included (PDF)\u003c\/a\u003e\u003c\/p\u003e\n\u003cp class=\"trd-caption\"\u003eProvided by Yoshimura. Opens in a new tab.\u003c\/p\u003e\u003c\/section\u003e\n\u003c\/div\u003e","brand":"Yoshimura","offers":[{"title":"Default Title","offer_id":68080838934679,"sku":"INS-21-K","price":40.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0585\/4884\/6743\/files\/yoshimura-ins-21-k-rs4-main.jpg?v=1792280369","url":"https:\/\/allamericanktm.com\/products\/yoshimura-sound-insert-kit-rs-4-muffler-1-500-ring-ins-21-k","provider":"All American KTM","version":"1.0","type":"link"}