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S&S Cycle offers MK-Series Performance crankcases for a variety of Harley-Davidson Touring and Softail street bikes from 2017 and up. These assembly replacements enable you to build massive power easily and reliably, particularly with M8 engines, and stock cases can't provide the necessary quality base. MK-Series crankcases are designed to allow for larger bores, scrape more oil than stock, have a larger volume sump, and fit in a stock frame without modification. Order the model recommended for your application.
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$2,849.95
The S&S Cycle 124 in. big bore/stroker Hot Set-Up kits transform a stock Harley-Davidson® engine into a 124 in. monster. It includes: 4 1/8 in. bore pistons; big bore cylinders finished in wrinkle black powdercoat; a dynamically balanced 4 5/8 in. stroke 3-piece flywheel assembly complete with heavy-duty connecting rods and integral mainshafts; 640 gear drive Easy Start camshafts; chromoly steel adjustable pushrods; premium tappets; and Super Stock 91cc cylinder heads. When installed, the kits yield a 124 in. engine with a compression ratio of 11:1. Although the engine is .960 in. taller than stock, there are no frame clearance problems—and a stock EFI throttle body will fit, because the manifold mounting surfaces of the heads have been specially machined to fit a stock length manifold. If you ride a 2006 HD Dyna model, or a balanced or non-balanced Big Twin from 2007-17, these top-end engine rebuild kits are for you. Note: No fuel or ignition system is included. However, for the best results, a larger EFI throttle body, performance intake, and performance exhaust are recommended. The EFI system must be recalibrated. Although not mandatory, S&S recommends adding an oil cooler to bikes ridden in warmer climates. S&S does not recommend compression ratios higher than 10:1 for Tri Glide or other 3-wheel models (including conversions) due to extra loads caused by the lugging nature of these bikes. Detonation and subsequent engine damage may result.
Not Yet Reviewed
$5,636.66
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