{"product_id":"prox-37-910002-front-master-cylinder-rebuild-kit-moto-house-mx","title":"ProX Front Master Cylinder Rebuild Kit 37.910002 — Honda \/ Yamaha \/ Kawasaki \/ Suzuki 1993-2026","description":"\u003ch1\u003e\u003cstrong\u003eProX Front Master Cylinder Rebuild Kit 37.910002 — Honda \/ Yamaha \/ Kawasaki \/ Suzuki 1993-2026\u003c\/strong\u003e\u003c\/h1\u003e\n\n\u003ch2\u003eProduct Description\u003c\/h2\u003e\n\n\u003cp\u003eRestore crisp, rock-solid braking performance and eliminate a spongy front lever with the \u003cstrong\u003eProX Front Master Cylinder Rebuild Kit\u003c\/strong\u003e. Over time, exposure to moisture, extreme heat, and deteriorating brake fluid deforms the internal rubber cups and corrodes the return piston inside your factory perch. This results in pressure loss, fluid bypass, or a front brake lever that slowly creeps back to the bars. This premium rebuild package updates your internal components to re-establish instant hydraulic pressure accuracy.\u003c\/p\u003e\n\n\u003cp\u003eEvery kit is sourced from world-class tier-one manufacturers and engineered to meet or strictly exceed OEM performance specifications. Packed with a precision-machined replacement piston, high-tension return spring, fresh fluid sealing cups, a new copper crush washer set, and an external rubber dust boot, this kit completely overhauls the wear components. Upgrading with ProX ensures factory-level feel and consistent stopping power down the longest racing motos.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eTop Features: ProX Master Cylinder Rebuild Kit\u003c\/strong\u003e\u003cbr\u003e\no Comprehensive front brake master cylinder kit including replacement piston, return spring, sealing cups, and hardware.\u003cbr\u003e\no Precision-molded rubber cup seals restore a leak-free hydraulic fitment match to prevent inner pressure drop.\u003cbr\u003e\no Manufactured to exact OEM dimensions for seamless drop-in placement inside factory front Nissin perches.\u003cbr\u003e\no Includes a fresh external rubber dust boot to aggressively lock out moisture, pressure-washer spray, and track silt.\u003c\/p\u003e\n\n\u003cp\u003e\u003cem\u003ePlease review the detailed compatibility data below to ensure an exact fitment match for your motorcycle before finalizing your purchase.\u003c\/em\u003e\u003c\/p\u003e\n\n\u003ch2\u003eFitment List\u003c\/h2\u003e\n\n\u003ctable\u003e\n\t\u003ctbody\u003e\n\t\t\u003ctr\u003e\n\t\t\t\u003cth\u003eYear Range\u003c\/th\u003e\n\t\t\t\u003cth\u003eVehicle Brand\u003c\/th\u003e\n\t\t\t\u003cth\u003eVehicle Model \u0026amp; Sub-Model\u003c\/th\u003e\n\t\t\u003c\/tr\u003e\n\t\t\u003ctr\u003e\n\t\t\t\u003ctd\u003e2004 - 2026\u003c\/td\u003e\n\t\t\t\u003ctd\u003eHonda\u003c\/td\u003e\n\t\t\t\u003ctd\u003eCRF250R \/ CRF250X \/ CRF450R \/ CRF450X\u003c\/td\u003e\n\t\t\u003c\/tr\u003e\n\t\t\u003ctr\u003e\n\t\t\t\u003ctd\u003e1999 - 2007\u003c\/td\u003e\n\t\t\t\u003ctd\u003eHonda\u003c\/td\u003e\n\t\t\t\u003ctd\u003eCR125R \/ CR250R \/ CR500R 2-Stroke\u003c\/td\u003e\n\t\t\u003c\/tr\u003e\n\t\t\u003ctr\u003e\n\t\t\t\u003ctd\u003e2001 - 2026\u003c\/td\u003e\n\t\t\t\u003ctd\u003eYamaha\u003c\/td\u003e\n\t\t\t\u003ctd\u003eYZ125 \/ YZ250 2-Stroke\u003c\/td\u003e\n\t\t\u003c\/tr\u003e\n\t\t\u003ctr\u003e\n\t\t\t\u003ctd\u003e2001 - 2023\u003c\/td\u003e\n\t\t\t\u003ctd\u003eYamaha\u003c\/td\u003e\n\t\t\t\u003ctd\u003eYZ250F \/ YZ450F \/ WR250F \/ WR450F\u003c\/td\u003e\n\t\t\u003c\/tr\u003e\n\t\t\u003ctr\u003e\n\t\t\t\u003ctd\u003e2004 - 2026\u003c\/td\u003e\n\t\t\t\u003ctd\u003eKawasaki\u003c\/td\u003e\n\t\t\t\u003ctd\u003eKX250F \/ KX450F \/ KX250 4-Stroke\u003c\/td\u003e\n\t\t\u003c\/tr\u003e\n\t\t\u003ctr\u003e\n\t\t\t\u003ctd\u003e2001 - 2025\u003c\/td\u003e\n\t\t\t\u003ctd\u003eKawasaki\u003c\/td\u003e\n\t\t\t\u003ctd\u003eKX85 \/ KX100 \/ KX112\u003c\/td\u003e\n\t\t\u003c\/tr\u003e\n\t\t\u003ctr\u003e\n\t\t\t\u003ctd\u003e2004 - 2026\u003c\/td\u003e\n\t\t\t\u003ctd\u003eSuzuki\u003c\/td\u003e\n\t\t\t\u003ctd\u003eRM-Z250 \/ RM-Z450\u003c\/td\u003e\n\t\t\u003c\/tr\u003e\n\t\t\u003ctr\u003e\n\t\t\t\u003ctd\u003e1996 - 2008\u003c\/td\u003e\n\t\t\t\u003ctd\u003eSuzuki\u003c\/td\u003e\n\t\t\t\u003ctd\u003eRM125 \/ RM250 2-Stroke\u003c\/td\u003e\n\t\t\u003c\/tr\u003e\n\t\u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: Does this kit include the front brake lever or the outer fluid reservoir body?\u003c\/strong\u003e\u003cbr\u003e\nA: No, this kit includes only the internal replacement piston assembly, springs, snap ring, washers, and seals required to rebuild the inside of your existing factory assembly.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: Will this rebuild kit function correctly if I have an aftermarket brake master cylinder?\u003c\/strong\u003e\u003cbr\u003e\nA: This kit is strictly designed to match factory OEM assemblies (typically original Nissin units). It will not fit aftermarket hydraulic setups like Brembo or Magura conversion master cylinders.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eQ: What type of brake fluid should be used when completing this rebuild?\u003c\/strong\u003e\u003cbr\u003e\nA: Always use fresh, high-quality fluid from a sealed container matching the specific rating stamped on your reservoir cap—typically high-temperature DOT 4 fluid for modern off-road machines.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eExpert Pro-Tip:\u003c\/strong\u003e When sliding the new rubber cup seals onto the replacement piston assembly, never install them bone-dry or use chemical sprays that can swell the rubber. Instead, coat the new piston and seals liberally with fresh, clean DOT 4 brake fluid. This acts as a safe lubricant, allowing the components to slide effortlessly into the cylinder bore without tearing or folding the critical seal edges during installation.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eRecommended Pairings:\u003c\/strong\u003e\u003cbr\u003e\no \u003ca href=\"https:\/\/motohousemx.com\/collections\/premium-motorcycle-chemicals-brake-fluid-bike-wash-coolant-chain-lubes\"\u003eMotorcycle Chemicals Performance Parts\u003c\/a\u003e\u003cbr\u003e\no \u003ca href=\"https:\/\/motohousemx.com\/collections\/mx-off-road-motorcycle-tools\"\u003eMotorcycle Tools Performance Parts\u003c\/a\u003e\u003cbr\u003e\no \u003ca href=\"https:\/\/motohousemx.com\/collections\/honda-crf250r-performance-parts-kits-and-accessories-moto-house-mx\"\u003eHonda CRF250R Performance Parts \u0026amp; Upgrades\u003c\/a\u003e\u003c\/p\u003e\n\n\u003cp\u003eAt Moto-House MX, we carry the best brands in motocross and off-road performance. Our team has over 40 years of experience helping riders get more out of their bikes. Every order ships fast from our Central Florida location.\u003c\/p\u003e\n\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eMoto-House MX – Choice of Champions\u003c\/strong\u003e – Clermont \/ Montverde, FL. Central Florida's premier powersports source with lightning-fast worldwide shipping.\u003c\/em\u003e\u003c\/p\u003e","brand":"Moto-House MX","offers":[{"title":"Default Title","offer_id":41080354570323,"sku":"37.910002","price":31.94,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1754\/5421\/files\/moto-house-mx-front-brake-master-cylinder-rebuild-kit-2003-2007-yamaha-yz450f-2001-2007-yz250f-123784.jpg?v=1735458666","url":"https:\/\/motohousemx.com\/products\/prox-37-910002-front-master-cylinder-rebuild-kit-moto-house-mx","provider":"Moto-House MX","version":"1.0","type":"link"}