{"product_id":"len-performance-front-track-shock-polaris-rmk-khaos-54-50004f","title":"Len Performance Front Track (Center) Shock, Polaris RMK Khaos AXYS \u0026 Matryx 2019–2026 (54-50004F)","description":"\u003cp\u003eLen Performance LS4-50004F rebuildable front track shock, also called the center shock, for the rear suspension on the Polaris 850 RMK Khaos 155 \/ 163 \/ 165 (AXYS, 2019–2021) and the 2022–2026 Matryx RMK Khaos and Khaos Slash 146 \/ 155 \/ 163 \/ 165 in 650, 850, Patriot 9R and Patriot Boost. It replaces the factory front track shock with a coil-over reservoir shock. At $557.95 each, it is A2D's value pick for a rebuildable, adjustable reservoir front track shock: clicker adjustment, a reservoir and a serviceable design without the cost of a race-level shock.\u003c\/p\u003e\u003cp\u003eThe front track shock controls how the skid loads under acceleration, how the front of the track carries weight on sidehills and how much ski pressure you keep when you get on the throttle. This shock has separate low-speed and high-speed compression clickers (8 low \/ 3 high, per Len Performance) and a threaded body with locking preload rings, so it can be set for rider weight and snow conditions instead of running fixed factory valving.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFitment.\u003c\/strong\u003e Sold each. Pairs with the Len Performance 54-50004R rear track shock for a complete rear suspension (Len Performance sells the pair as kit LS4-50004K). Matching ski shock: 54-50004. Chassis: Polaris AXYS (2019–2021 Khaos) and Matryx (2022–2026).\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFitment list\u003c\/strong\u003e (Len Performance year\/model lookup)\u003c\/p\u003e\u003cul\u003e\u003cli\u003e\n\u003cstrong\u003eRMK \/ Khaos:\u003c\/strong\u003e 2019-2026 850 RMK Khaos 155; 2019-2022 850 RMK Khaos 163\/165; 2019-2026 850 RMK Khaos 165; 2022-2026 650 RMK Khaos Slash 146 Matryx; 2022-2024 850 RMK Khaos Slash 146; 2022-2024 850 RMK Khaos Slash 155; 2022-2024 850 RMK Khaos Slash 163\/165; 2022-2026 Patriot Boost RMK Khaos Matryx 155; 2022-2024 Patriot Boost RMK Khaos Slash 155; 2023-2026 Patriot 9R RMK Khaos 146 Matryx; 2023-2026 Patriot 9R RMK Khaos 155 Matryx; 2023-2026 Patriot 9R RMK Khaos 165 Matryx; 2023-2024 Patriot 9R RMK Khaos Slash 146; 2023-2024 Patriot 9R RMK Khaos Slash 155; 2023-2024 Patriot 9R RMK Khaos Slash 163\/165; 2023-2024 Patriot Boost RMK Khaos Slash 163\/165; 2025-2026 850 RMK Khaos 146; 2025-2026 Patriot 9R RMK Khaos 155 LE; 2025-2026 Patriot Boost RMK Khaos 165; 2026 Patriot Boost RMK Khaos 155 LE\u003c\/li\u003e\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eFeatures\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eSeparate low-speed and high-speed compression clickers: 8-click low-speed and 3-click high-speed compression adjustment (per Len Performance).\u003c\/li\u003e\n\u003cli\u003eAluminum reservoir shock: the remote-style reservoir keeps oil temperature down and damping consistent on long pulls.\u003c\/li\u003e\n\u003cli\u003eFully rebuildable, serviceable shock. Len Performance rebuild kits and replacement parts are available.\u003c\/li\u003e\n\u003cli\u003eHardened chromoly shaft for strength and seal life.\u003c\/li\u003e\n\u003cli\u003eForged aluminum eyelet heads with premium steel and NBR bushings.\u003c\/li\u003e\n\u003cli\u003ePowder-coated spring resists corrosion and holds rate in cold, wet conditions.\u003c\/li\u003e\n\u003cli\u003eThreaded shock body with anodized dual-ring locking preload adjusters: set sag once and it stays set.\u003c\/li\u003e\n\u003cli\u003eSold each.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eSpecifications\u003c\/strong\u003e\u003c\/p\u003e\u003ctable\u003e\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003ePart number\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e54-50004F (Len Performance LS4-50004F)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOEM part number replaced\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e7045531 (per distributor listings)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eShock location\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eFront track shock \/ center shock (rear suspension)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eChassis \/ platform\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003ePolaris AXYS \/ Matryx\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eAdjustments\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eCompression (8 low-speed \/ 3 high-speed), plus threaded spring preload\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eLength, extended\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e306 mm \/ 12.05 in\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eLength, compressed\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e213 mm \/ 8.39 in\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eStroke\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e93 mm \/ 3.66 in\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eSpring\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003ePowder-coated coil spring included, 72 mm \/ 2.84 in diameter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTop eyelet\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e20.5 mm ID x 21.8 mm wide (0.81 in x 0.86 in)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eBottom eyelet\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e18 mm ID x 29.5 mm wide (0.71 in x 1.17 in)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eWeight\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e4.45 lb\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eIncludes\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eOne shock\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eRebuild kit\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eLen Performance rebuild kits available; call to confirm the kit number for this shock\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eSold\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eEach\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\u003c\/table\u003e\u003cp\u003e\u003cstrong\u003eOrdering and installation.\u003c\/strong\u003e Sold each. Ships from stock at our Anchorage shop, or from our distributor's Boise, Idaho warehouse when not on the shelf. In-store pickup is available at checkout. Installation and shock setup are available at A2D Motorsports; call (907) 306-3062 to schedule. Len Performance rebuild kits are available, so the shock can be serviced or re-valved rather than replaced.\u003c\/p\u003e","brand":"Len Performance","offers":[{"title":"Default Title","offer_id":48791217275125,"sku":"54-50004F","price":557.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0800\/0267\/9029\/files\/len-54-50004F.jpg?v=1790126828","url":"https:\/\/a2dmotorsports.net\/products\/len-performance-front-track-shock-polaris-rmk-khaos-54-50004f","provider":"Shop A2D Motorsports ","version":"1.0","type":"link"}