{"product_id":"vertex-wr101-081-complete-engine-rebuild-kit-1998-2021-yamaha-yz125-2020-2022-yz125x","title":"Vertex WR101-081 Complete Engine Rebuild Kit - 1998-2021 Yamaha YZ125 \/ 2020-2022 YZ125X","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\n\u003cp\u003eWhen it's time to restore the crisp, high-RPM scream of your 125, a basic top-end patch job won't cut it. The Vertex Complete Engine Rebuild Kit Collection delivers a premium, comprehensive \"engine-in-a-box\" solution to fully revitalize your machine's power plant from the deep bottom-end right back up to the top. Moto-House MX provides these high-performance packages featuring premium Vertex and Hot Rods components to ensure absolute crankcase compression, zero air leaks, and factory-fresh track reliability across multiple generations of the Yamaha YZ125.\u003c\/p\u003e\n\u003cp\u003eManufactured to strict precision tolerances, these setups completely eliminate the frustration of chasing down individual engine parts. Frontlined by a heavy-duty Hot Rods crankshaft and a world-class Vertex standard compression piston kit, every piece is engineered to handle the relentless stress of 2-stroke racing performance. Select your exact year from our comprehensive master application guide below and rebuild your machine the right way!\u003c\/p\u003e\n\u003ch3\u003eTop Features: VERTEX Complete 2-Stroke Engine Rebuild Kits\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cb\u003ePremium Brand Integration:\u003c\/b\u003e Features a world-renowned Vertex standard compression piston kit packaged with a heavy-duty, factory-stroke Hot Rods crankshaft assembly.\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eComplete Bearing Infrastructure:\u003c\/b\u003e Includes specialized Hot Rods kits for main bearings, complete transmission bearings, counter-balancer bearings, and a dedicated water pump rebuild setup.\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eTotal Sealing Package:\u003c\/b\u003e Includes a full Vertex engine gasket kit with all necessary oil seals and precision cylinder O-rings for complete top and bottom-end restoration.\u003c\/li\u003e\n\u003cli\u003e\n\u003cb\u003eYear-Specific Grouping:\u003c\/b\u003e Easily locate the exact manufacturer part number assigned to your model year for an absolute, zero-modification fit.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cb\u003eDon't let an old, worn-out crank ruin a fresh top end—verify your fitment list below, find your part number, and refresh your machine today!\u003c\/b\u003e\u003c\/p\u003e\n\u003ch3\u003eMaster Fitment \u0026amp; Part Number Selection Guide\u003c\/h3\u003e\n\u003ctable style=\"border-collapse: collapse; width: 100%; max-width: 600px;\" cellpadding=\"8\" border=\"1\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth style=\"text-align: left; background-color: #f2f2f2;\"\u003eYear Range\u003c\/th\u003e\n\u003cth style=\"text-align: left; background-color: #f2f2f2;\"\u003eVehicle Brand\u003c\/th\u003e\n\u003cth style=\"text-align: left; background-color: #f2f2f2;\"\u003eVehicle Model\u003c\/th\u003e\n\u003cth style=\"text-align: left; background-color: #f2f2f2;\"\u003eVertex Part Number\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e1998-2000\u003c\/td\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eYZ125 (2-Stroke)\u003c\/td\u003e\n\u003ctd\u003e\u003cb\u003eWR101-093\u003c\/b\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2001\u003c\/td\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eYZ125 (2-Stroke)\u003c\/td\u003e\n\u003ctd\u003e\u003cb\u003eWR101-125\u003c\/b\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2002-2004\u003c\/td\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eYZ125 (2-Stroke)\u003c\/td\u003e\n\u003ctd\u003e\u003cb\u003eWR101-094\u003c\/b\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2005-2021\u003c\/td\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eYZ125 (2-Stroke)\u003c\/td\u003e\n\u003ctd\u003e\u003cb\u003eWR101-081\u003c\/b\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2020-2022\u003c\/td\u003e\n\u003ctd\u003eYamaha\u003c\/td\u003e\n\u003ctd\u003eYZ125X (Cross Country 2-Stroke)\u003c\/td\u003e\n\u003ctd\u003e\u003cb\u003eWR101-081\u003c\/b\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003e\u003cb\u003eQ: How do I know which Vertex part number applies to my specific bike?\u003c\/b\u003e\u003cbr\u003eA: Simply use our Master Fitment Chart above. Locate your exact YZ125 model year to identify the matching Vertex part code (e.g., WR101-081 fits the 2005–2021 YZ125).\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eQ: Do these kits include everything for both the bottom and top end?\u003c\/b\u003e\u003cbr\u003eA: Yes, every package in this collection is a complete engine overhaul kit containing the crankshaft, main bearings, seals, transmission bearings, complete gaskets, and the piston assembly.\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eQ: Can these kits be used for high-level racing applications?\u003c\/b\u003e\u003cbr\u003eA: Absolutely. Vertex and Hot Rods engine components are heavily trusted for competitive race builds, offering race-ready durability and consistent performance under extreme track heat.\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eExpert Pro-Tip:\u003c\/b\u003e The Yamaha YZ125 requires flawless crankcase alignment during assembly to prevent premature main bearing wear. When joining the case halves, never use the case bolts to force the engine together. Always use a proper crank puller\/installer tool to smoothly seat the crankshaft into the bearings, checking that the crank spins completely free before performing final case torquing.\u003c\/p\u003e\n\u003ch3\u003eRecommended Pairings:\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"\/search?q=YZ125+Engine\"\u003eShop Yamaha YZ125 Engine Performance Parts \u0026amp; Accessories\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/search?q=2-Stroke+Oil\"\u003eBrowse Premium 2-Stroke Premix Oils \u0026amp; Transmission Fluids\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"\/search?q=Vertex\"\u003eBrowse All Vertex Engine Components\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eStop by our local store in Montverde, FL or enjoy lightning-fast shipping across the USA.\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eMoto-House MX – Choice of Champions\u003c\/b\u003e – is located in Clermont\/Montverde, FL. The Best Motocross\/UTV \u0026amp; ATV Shop in Central Florida.\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e","brand":"Wrench Rabbit","offers":[{"title":"YZ125 - 1998-2000","offer_id":12285841244243,"sku":"WR101-093","price":649.36,"currency_code":"USD","in_stock":true},{"title":"YZ125 - 2001","offer_id":12285841277011,"sku":"WR101-125","price":627.26,"currency_code":"USD","in_stock":true},{"title":"YZ125 - 2002-2004","offer_id":12285841309779,"sku":"WR101-094","price":650.12,"currency_code":"USD","in_stock":true},{"title":"YZ125 - 2005-2021 \/ YZ125X - 2020-2022","offer_id":12285841342547,"sku":"WR101-081","price":628.0,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1754\/5421\/files\/vertex-engine-complete-rebuild-kit-wrench-rabbit-1998-2022-yamaha-yz125-and-yz125x-2020-2022-609728.jpg?v=1735463503","url":"https:\/\/motohousemx.com\/products\/vertex-wr101-081-complete-engine-rebuild-kit-1998-2021-yamaha-yz125-2020-2022-yz125x","provider":"Moto-House MX","version":"1.0","type":"link"}