{"product_id":"1200cc-piston-set-040-oversize-keith-black-kb295-040-evolution-sportster-1988","title":"1200cc Piston Set.040 Oversize - Keith Black KB295 .040 - Evolution Sportster 1988+","description":"\u003cp\u003e\u003cstrong\u003eKeith Black #:\u003c\/strong\u003e KB295 .040\u003c\/p\u003e\n\u003cp\u003eKeith Black flat top piston set is.040 oversize with a 8.9:1 compression ratio for 1988-up XL 1200cc Evolution models.\u003c\/p\u003e\n\u003cp\u003eThe Keith Black 390 hypereutectic alloy is cast in a permanent steel mold which makes it possible to build a light weight piston that makes more power and uses less fuel and lasts longer. Pistons are.040 oversize for a 3.498 inch bore and has a 9:1 compression ratio. The low heat transfer of the alloy keeps the skirts cool so piston expansion is minimal. The combination of a low heat transfer piston alloy and high compression ring placement increases power and economy. The high ring placement alone reduces detonation and increases the top ring temperature. **Note: Run engine at moderate speeds for at least 500 miles avoiding excessive running in lower gears in order to properly break-in new pistons and rings.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eFitment:\u003c\/strong\u003e\u003c\/p\u003e\u003ctable\u003e\u003ctbody\u003e\u003ctr\u003e\n\u003ctd\u003e1988-UP\u003c\/td\u003e\n\u003ctd\u003eXL\u003c\/td\u003e\n\u003c\/tr\u003e\u003c\/tbody\u003e\u003c\/table\u003e\n\u003cp\u003e\u003ca href=\"http:\/\/www.vtwinmfg.com\/Instructions\/MS\/KB%20Sym-Asym%20Piston%20Installation%20Guide.pdf\" target=\"_blank\" rel=\"noopener\"\u003eInstallation instructions (PDF)\u003c\/a\u003e\u003c\/p\u003e","brand":"Keith Black","offers":[{"title":"Default Title","offer_id":67549414162590,"sku":"11-2250","price":259.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1692\/2127\/files\/11-2250-1200cc-piston-set-040-oversize-keith-black-kb295-040-evolution-sportster-1988-1.jpg?v=1792100563","url":"https:\/\/chopcult.com\/products\/1200cc-piston-set-040-oversize-keith-black-kb295-040-evolution-sportster-1988","provider":"ChopCult","version":"1.0","type":"link"}