{"product_id":"len-performance-rear-track-shock-polaris-switchback-assault-sks-54-50000r","title":"Len Performance Rear Track Shock, Polaris Switchback Assault 144 \/ 146, Switchback XCR \u0026 SKS 146 2017–2026 (54-50000R)","description":"\u003cp\u003eLen Performance LS4-50000R rebuildable rear track shock for the rear suspension on the 2017–2021 AXYS Switchback Assault 144 (600 \/ 800 \/ 850), 2018–2021 AXYS SKS 146 (800 \/ 850), 2019–2021 850 Switchback XCR and the 2021–2026 Matryx Switchback Assault 146 (650, 850, Patriot 9R and Patriot Boost). It replaces the factory rear track shock with a reservoir shock that has 5-click compression adjustment. At $394.95 each, it is A2D's value pick for a rebuildable, adjustable reservoir rear track shock: clicker adjustment, a reservoir and a serviceable design without the cost of a race-level shock.\u003c\/p\u003e\u003cp\u003eThe rear track shock sets how the skid handles big hits, deep-snow re-entries and bottoming with gear on the tunnel. This is a springless unit that works with the factory rear torsion springs, so it drops in without changing the rest of the skid.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFitment.\u003c\/strong\u003e Sold each. Pairs with the Len Performance 54-50000F front track shock for a complete rear suspension (Len Performance sells the pair as kit LS4-50000K). Matching ski shock: 54-50000 (Switchback Assault \/ XCR) or 54-50002 (SKS). Chassis: Polaris AXYS (2017–2021) and Matryx (2021–2026).\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFitment list\u003c\/strong\u003e (Len Performance year\/model lookup)\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSwitchback:\u003c\/strong\u003e 2017-2021 600 Switchback Assault AXYS 144; 2017-2020 800 Switchback Assault AXYS 144; 2019-2021 850 Switchback Assault AXYS 144; 2019-2021 850 Switchback XCR; 2021-2026 650 Switchback Assault 146 Matryx; 2021-2026 850 Switchback Assault 146 Matryx; 2023-2026 Patriot Boost Switchback Assault 146 Matryx; 2025 Patriot 9R Switchback Assault 146 Matryx\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSKS:\u003c\/strong\u003e 2018-2020 800 SKS AXYS 146; 2019-2021 850 SKS AXYS 146\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eFeatures\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003e5-click compression adjustment, tool-free.\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\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\u003e54-50000R (Len Performance LS4-50000R)\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\u003e7044379 (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\u003eRear track 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 (5)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eLength, extended\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e490 mm \/ 19.3 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\u003e327 mm \/ 12.9 in\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eStroke\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e163 mm \/ 6.4 in\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eSpring\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eNone (uses the factory torsion springs)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTop eyelet\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e17.7 mm ID x 29.3 mm wide (0.7 in x 1.2 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\u003e15.9 mm ID x 29.2 mm wide (0.6 in x 1.1 in)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eWeight\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e3.55 lb (6 lb shipping)\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\u003e54-00003 (Len LSR-00003), per Dennis Kirk\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":50446072217845,"sku":"54-50000R","price":394.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0800\/0267\/9029\/files\/len-54-50000R.jpg?v=1790126310","url":"https:\/\/a2dmotorsports.net\/products\/len-performance-rear-track-shock-polaris-switchback-assault-sks-54-50000r","provider":"Shop A2D Motorsports ","version":"1.0","type":"link"}