{"product_id":"keith-black-80-inch-evolution-flat-piston-set-005-for-harley-davidson-fxr","title":"Keith Black 80 Inch Evolution Flat Piston Set.005 8.6:1 Harley FXR 1984-1993","description":"\u003cdiv\u003e\n\u003ch1\u003eKeith Black 80 Inch Evolution Flat Piston Set.005 Oversize for Harley FXR (1984–1993)\u003c\/h1\u003e\n\u003cp\u003eKeith Black's Evolution flat-top pistons in.005 oversize are engineered for Harley-Davidson FXR models from 1984 to 1993, delivering a 3.498 in bore with an 8.5:1 compression ratio. The KB258.005 80 Inch Evolution Flat Piston Set is crafted from hypereutectic alloy and cast in a permanent steel mold to ensure precision, durability, and consistent performance.\u003c\/p\u003e\n\u003cp\u003eThe design features a.005 inch oversize to precisely fit a 3.498 inch bore, providing a reliable upgrade that can improve engine power and efficiency. The low heat transfer alloy helps keep piston skirts cooler, reducing expansion and wear over time. High ring placement together with the alloy properties enhances power output while helping resist detonation, contributing to better top-end temperature management and long-term engine reliability.\u003c\/p\u003e\n\u003cul\u003e \u003cli\u003eMaterial: Hypereutectic alloy\u003c\/li\u003e \u003cli\u003eCasting: Permanent steel mold\u003c\/li\u003e \u003cli\u003eOversize:.005 inch\u003c\/li\u003e \u003cli\u003eBore: 3.498 in\u003c\/li\u003e \u003cli\u003eCompression Ratio: 8.5:1\u003c\/li\u003e \u003cli\u003eHeat Transfer: Low\u003c\/li\u003e \u003cli\u003eDesign: High ring placement\u003c\/li\u003e \u003cli\u003eBreak-in Instructions: Run engine at moderate speeds for at least 500 miles\u003c\/li\u003e \u003cli\u003eCountry of Origin: USA\u003c\/li\u003e \u003cli\u003eFitment: Harley Davidson FXR 1984–1993\u003c\/li\u003e \u003cli\u003ePart Number: KB258.005\u003c\/li\u003e\n\u003c\/ul\u003eKeith Black flat top piston set is.005 oversize with an 8.6:1 compression ratio for 1984-up Big Twin Evolution models.\n\u003cp\u003eThe Keith Black KB258.005 80 Inch Evolution Flat Piston Set is engineered for optimal performance in Harley Davidson FXR models from 1984 to 1993. Crafted from hypereutectic alloy, these pistons are cast in a permanent steel mold, ensuring durability and precision. The design features a.005 inch oversize to fit a 3.498 inch bore, providing a reliable upgrade that enhances engine power and efficiency. The pistons have an 8.5:1 compression ratio, balancing performance and fuel economy effectively. The low heat transfer alloy helps keep the piston skirts cool, minimizing expansion and reducing wear over time. High compression ring placement and the alloy's properties work together to boost engine power while decreasing detonation, leading to improved top-end temperature management and overall engine longevity.\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eFeatures:\u003c\/b\u003e\u003c\/p\u003e\n\u003cul\u003e\u003cli\u003eMaterial: Hypereutectic alloy for durability and heat resistance\u003c\/li\u003e\u003c\/ul\u003e\n\u003cul\u003e\u003cli\u003eCasting: Permanent steel mold for precision and consistency\u003c\/li\u003e\u003c\/ul\u003e\n\u003cul\u003e\u003cli\u003eOversize:.005 inch for a perfect fit in a 3.498 inch bore\u003c\/li\u003e\u003c\/ul\u003e\n\u003cul\u003e\u003cli\u003eCompression Ratio: 8.5:1 for balanced power and fuel efficiency\u003c\/li\u003e\u003c\/ul\u003e\n\u003cul\u003e\u003cli\u003eHeat Transfer: Low heat transfer alloy reduces piston skirt temperature\u003c\/li\u003e\u003c\/ul\u003e\n\u003cul\u003e\u003cli\u003eDesign: High ring placement enhances power output and detonation resistance\u003c\/li\u003e\u003c\/ul\u003e\n\u003cul\u003e\u003cli\u003eBreak-in Instructions: Run engine at moderate speeds for at least 500 miles to ensure proper piston and ring seating\u003c\/li\u003e\u003c\/ul\u003e\n\u003cul\u003e\u003cli\u003eCountry of Origin: USA\u003c\/li\u003e\u003c\/ul\u003e\n\u003cbr\u003e\nFitment:\u003cbr\u003e\nHarley Davidson FLST 1986\u003cbr\u003e\nHarley Davidson FLST 1987\u003cbr\u003e\nHarley Davidson FLST 1988\u003cbr\u003e\nHarley Davidson FLST 1989\u003cbr\u003e\nHarley Davidson FLST 1990\u003cbr\u003e\nHarley Davidson FLST 1991\u003cbr\u003e\nHarley Davidson FLST 1992\u003cbr\u003e\nHarley Davidson FLST 1993\u003cbr\u003e\nHarley Davidson FLST 1994\u003cbr\u003e\nHarley Davidson FLST 1995\u003cbr\u003e\nHarley Davidson FLST 1996\u003cbr\u003e\nHarley Davidson FLST 1997\u003cbr\u003e\nHarley Davidson FLST 1998\u003cbr\u003e\nHarley Davidson FLT 1984\u003cbr\u003e\nHarley Davidson FLT 1985\u003cbr\u003e\nHarley Davidson FLT 1986\u003cbr\u003e\nHarley Davidson FLT 1987\u003cbr\u003e\nHarley Davidson FLT 1988\u003cbr\u003e\nHarley Davidson FLT 1989\u003cbr\u003e\nHarley Davidson FLT 1990\u003cbr\u003e\nHarley Davidson FLT 1991\u003cbr\u003e\nHarley Davidson FLT 1992\u003cbr\u003e\nHarley Davidson FLT 1993\u003cbr\u003e\nHarley Davidson FLT 1994\u003cbr\u003e\nHarley Davidson FLT 1995\u003cbr\u003e\nHarley Davidson FLT 1996\u003cbr\u003e\nHarley Davidson FLT 1997\u003cbr\u003e\nHarley Davidson FLT 1998\u003cbr\u003e\nHarley Davidson FXD 1991\u003cbr\u003e\nHarley Davidson FXD 1992\u003cbr\u003e\nHarley Davidson FXD 1993\u003cbr\u003e\nHarley Davidson FXD 1994\u003cbr\u003e\nHarley Davidson FXD 1995\u003cbr\u003e\nHarley Davidson FXD 1996\u003cbr\u003e\nHarley Davidson FXD 1997\u003cbr\u003e\nHarley Davidson FXD 1998\u003cbr\u003e\nHarley Davidson FXR 1984\u003cbr\u003e\nHarley Davidson FXR 1985\u003cbr\u003e\nHarley Davidson FXR 1986\u003cbr\u003e\nHarley Davidson FXR 1987\u003cbr\u003e\nHarley Davidson FXR 1988\u003cbr\u003e\nHarley Davidson FXR 1989\u003cbr\u003e\nHarley Davidson FXR 1990\u003cbr\u003e\nHarley Davidson FXR 1991\u003cbr\u003e\nHarley Davidson FXR 1992\u003cbr\u003e\nHarley Davidson FXR 1993\u003cbr\u003e\nHarley Davidson FXR 1994\u003cbr\u003e\nHarley Davidson FXST 1984\u003cbr\u003e\nHarley Davidson FXST 1985\u003cbr\u003e\nHarley Davidson FXST 1986\u003cbr\u003e\nHarley Davidson FXST 1987\u003cbr\u003e\nHarley Davidson FXST 1988\u003cbr\u003e\nHarley Davidson FXST 1989\u003cbr\u003e\nHarley Davidson FXST 1990\u003cbr\u003e\nHarley Davidson FXST 1991\u003cbr\u003e\nHarley Davidson FXST 1992\u003cbr\u003e\nHarley Davidson FXST 1993\u003cbr\u003e\nHarley Davidson FXST 1994\u003cbr\u003e\nHarley Davidson FXST 1995\u003cbr\u003e\nHarley Davidson FXST 1996\u003cbr\u003e\nHarley Davidson FXST 1997\u003cbr\u003e\nHarley Davidson FXST 1998\u003c\/div\u003e","brand":"Keith Black","offers":[{"title":"Default Title","offer_id":44653157711914,"sku":"11-2217","price":198.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0692\/2285\/8794\/files\/11-2217.jpg?v=1785887969","url":"https:\/\/atticusgoods.com\/products\/keith-black-80-inch-evolution-flat-piston-set-005-for-harley-davidson-fxr","provider":"Atticus Goods","version":"1.0","type":"link"}