{"product_id":"4045m08750-wiseco-piston-kit-020-for-yamaha-sr500-1978-1981-87-50mm-10-1-cr","title":"4045M08750 Wiseco Piston Kit .020 for Yamaha SR500 1978-1981 87.50mm 10:1 CR","description":"\u003ch2\u003eWiseco .020 Piston Kit for Yamaha SR500\u003c\/h2\u003e\u003cp\u003eThis Wiseco .020 piston kit for Yamaha SR500 1978-1981 models runs an 87.50 mm bore at a 10:1 compression ratio, cross-referenced under Wiseco part number 4045M08750.\u003c\/p\u003e\u003ch4\u003eOverview\u003c\/h4\u003e\u003cp\u003eThis Wiseco .020 piston kit is a high-compression top-end component for the Yamaha SR500 built from 1978 to 1981. The piston kit raises compression to 10:1 on an 87.50 mm overbore, delivering stronger response from the SR500 single. It suits riders and builders refreshing a worn top end or chasing more punch from the thumper engine.\u003c\/p\u003e\u003ch4\u003eBuilt For Performance\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003e87.50 mm piston diameter matched to a 0.020 inch overbore\u003c\/li\u003e\n\u003cli\u003e10:1 compression ratio for stronger mid-range output\u003c\/li\u003e\n\u003cli\u003eWiseco 4045M08750 part number for precise cross-reference\u003c\/li\u003e\n\u003cli\u003eForged piston construction rated for higher cylinder pressure\u003c\/li\u003e\n\u003cli\u003eKit format supplies the piston for a complete top-end rebuild\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eFits These Machines\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003efor Yamaha SR500 1978\u003c\/li\u003e\n\u003cli\u003efor Yamaha SR500 1979\u003c\/li\u003e\n\u003cli\u003efor Yamaha SR500 1980\u003c\/li\u003e\n\u003cli\u003efor Yamaha SR500 1981\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eOn-The-Job Use\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003eTop-end rebuilds after cylinder honing or boring\u003c\/li\u003e\n\u003cli\u003ePerformance refresh on a high-mileage SR500 engine\u003c\/li\u003e\n\u003cli\u003eVintage thumper engine rebuild and service work\u003c\/li\u003e\n\u003cli\u003eBuilds where a higher compression ratio is wanted\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eSpecs At A Glance\u003c\/h4\u003e\u003ctable\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003ePart Number(s)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e4045M08750\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eBore Size\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e87.50 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOverbore\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e.020 inch\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eCompression Ratio\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e10:1\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eMachine Fitment\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003efor Yamaha SR500 1978-1981\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\u003ch4\u003eGood To Know\u003c\/h4\u003e\u003cp\u003e\u003cstrong\u003eQ:\u003c\/strong\u003e Does this piston kit require cylinder machining? \u003cstrong\u003eA:\u003c\/strong\u003e A 0.020 inch overbore piston needs the cylinder bored and honed to match the 87.50 mm size before assembly. Confirm the current bore condition with your machinist first.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eQ:\u003c\/strong\u003e Will the 10:1 ratio work with my setup? \u003cstrong\u003eA:\u003c\/strong\u003e Higher compression can require premium fuel and correct jetting to avoid detonation on the SR500. Check your fuel, ignition, and carburetion before running it.\u003c\/p\u003e\u003cp\u003e\u003cem\u003eSlight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.\u003c\/em\u003e\u003c\/p\u003e","brand":"Solid Spare","offers":[{"title":"Default Title","offer_id":51140127883350,"sku":"OO1C22585","price":523.59,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0697\/8460\/0662\/files\/s-l1600_b4b57b7a-ba6b-4bff-aed7-f29a7d49b345.jpg?v=1794565988","url":"https:\/\/www.solidspare.com\/products\/4045m08750-wiseco-piston-kit-020-for-yamaha-sr500-1978-1981-87-50mm-10-1-cr","provider":"Solid Spare","version":"1.0","type":"link"}