{"product_id":"61973-performance-tappet-assemblies-for-most-models","title":"Hydraulic Performance Tappet Big Twin Evo 84 \/ 89 Sportster 86 \/ 90 Race Design","description":"\u003ch1\u003ePERFORMANCE TAPPET ASSEMBLIES FOR MOST MODELS\u003c\/h1\u003eWEIGHT: 0.41\u003cbr\u003e\u003cul\u003e\n\u003cli\u003eTHESE PERFORMANCE TAPPETS OFFER PREMIUM PERFORMANCE , STRENGTH AND RELIABILITY AT A REASONABLE PRICE\u003c\/li\u003e\n\u003cli\u003eMADE OF HIGH STRENGTH STEEL ALLOY AND HEAT TREATED FOR STRENGTH AND WEAR RESISTANCE\u003c\/li\u003e\n\u003cli\u003eTHE INTERNAL PARTS ARE MACHINED TO TOLERANCES FOR LONG LASTING USE\u003c\/li\u003e\n\u003cli\u003eSOLD EACH\u003c\/li\u003e\n\u003c\/ul\u003e\u003cb\u003eTYPES OF HYDRAULIC LIFTERS:\u003c\/b\u003e\u003cbr\u003e\u003cbr\u003e\u003cb\u003eOEM DESIGN:\u003c\/b\u003e THESE LIFTERS ARE MANUFACTURED TO BE DIRECT REPLACEMENTS FOR THE ORIGINAL EQUIPMENT. THEY HAVE THE SAME RANGE OF LEAK DOWN AS WAS SUPPLIED TO YOUR OE LIFTER. THESE LIFTERS ARE MADE WITH THE WIDEST LEAK DOWN RANGE OF 10 TO 120 SECONDS. THE REASON FOR THIS RANGE IS TO EASE MANUFACTURING AND REDUCE THE COST OF THE PART. WE MANUFACTURE THIS TYPE OF PART TO THE SAME RANGE AS WAS SUPPLIED TO THE OEM.\u003cbr\u003e\u003cbr\u003e\u003cb\u003ePRO STREET DESIGN:\u003c\/b\u003e THESE LIFTERS HAVE A LEAK DOWN ON THE UPPER END OF THE SCALE FROM 90 TO 120 SECONDS. IN A PERFORMANCE APPLICATION , THESE LIFTERS WILL ACTUALLY ACT LIKE A MECHANICAL LIFTER WITH VERY LITTLE EFFECTIVE LOSS OF VALVE LIFT OR DURATION AT ANY RPM. THEY ALSO HAVE A POSITIVE RETAINER INSTEAD OF THE OEM WIRE CLIP DESIGN. THESE LIFTERS ARE VERY HARD TO PRODUCE BECAUSE THE TOTAL CLEARANCE BETWEEN THE I.D. OF THE BODY AND PISTON ASSEMBLY IS REDUCED TO LESS THAN 0.000120\" OR 1\/30 OF A HUMAN HAIR. THESE ARE LIKE SUPER HEAVY-DUTY SHOCKS AND CAN HANDLE HIGHER SPRING PRESSURES WITHOUT COLLAPSING LIKE THE OEM AND RACE LIFTERS.\u003cbr\u003e\u003cbr\u003e\u003cb\u003eRACE DESIGN:\u003c\/b\u003e THESE LIFTERS HAVE A LEAK DOWN ON THE LOWER END OF THE SCALE FROM 8 TO 10 SECONDS. IN THE PERFORMANCE APPLICATION , THESE LIFTERS WILL ACTUALLY \"BLEED\" DOWN AND RESULT IN AN EFFECTIVE LOSS OF VALVE LIFT AND DURATION AT LOWER RPM'S. THESE ARE ALSO REFERRED TO AS \"VARIABLE DURATION\" LIFTERS AND WILL SUPPLY A BETTER IDLE QUALITY WHEN USING A PERFORMANCE CAM , WHILE STILL GETTING THE BENEFIT OF THE UPPER END POWER OVER A STOCK CAM. AS THE ENGINE INCREASES IN RPM THE BLEED DOWN EFFECT IS REDUCED , RESULTING IN MORE DURATION AND VALVE LIFT. THESE LIFTERS HAVE A POSITIVE RETAINER INSTEAD OF THE OEM WIRE CLIP DESIGN. DON'T BE FOOLED , AND MAKE SURE THEY ARE MANUFACTURED AS FAST LEAK LIFTERS AND NOT JUST A STOCK LIFTER WITH A NICE RETAINER.\u003cbr\u003e\u003cb\u003ePOWER HOUSE\u003c\/b\u003e\u003cbr\u003eSTD O.D.\u003cbr\u003eRACE DESIGN HYDRAULIC TAPPET\u003cbr\u003eFITS BIG TWIN EVOLUTION 1984\/1999 \u0026amp; SPORTSTER 1986\/1990","brand":"MID-USA","offers":[{"title":"Default Title","offer_id":20200062353519,"sku":"61973","price":86.1,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0081\/7401\/0479\/products\/0075101_0.jpg?v=1575432652","url":"https:\/\/www.widowmakersboneyard.com\/products\/61973-performance-tappet-assemblies-for-most-models","provider":"Widowmaker's Boneyard","version":"1.0","type":"link"}