1986-2013 Sportster® & Buell - S&S Cycle

S e ction 4: 1986-2013 Sportster® & Buell ®S&S®Parts forTwin Cam 96 /103 2007-2013Parts forTwin Cam 88 ®1999-2006Sidewinder ® Big Bore KitsWhen the Harley-Davidson® Evolution® powered Sportster® was released in 1986 it was obvious thatthe new engine had a lot of potential. Aside from the obvious benefit of aluminum finned cylindersand a modern cylinder head and valve train, the crankcases were beefed up enough to handle largerbore sizes with far fewer problems than previous engines. The crankcase cylinder deck height wasraised to be the same as a big twin engine at 5.375" from the center of the crankshaft, and the caseswere stronger in general so that material did not have to be welded on to the sides of the cylinderdeck in order to accommodate 35/8" bore cylinders. The taller crankcase deck did result in cylindersthat were too short to allow a practical stock bore stroker to be designed, so big bore was the onlyoption!Parts forEvolution ®1984-1999Parts forSportster ® & Buell ®1986-2013Parts forVintage Engines1926-1984Parts forX-Wedge®2007-2012PERFORMANCEKITSFITMENT• 1986-'03 Harley-Davidson® Sportster®• 1994-'02 Harley-Davidson® Buell®FEATURES AND BENEFITS• Available in three displacements, for four-speed (1986-’90) and five-speed (1991-’03) models,and in natural aluminum and black powdercoat finish.• Two displacements available : 79" and 89" big bore stroker kit• Requires that the crankcase cylinder spigot holes be bored to accept the larger cylinders• Complete instructions are provided for this machining operation, and S&S has special toolsavailable that simplify the crankcase boring procedure. See Section 9 in this catalog for moreinformation91-3123This Sidewinder® Big Bore kit is for 1991-2003 89" Sportster® models. These enginesrequire require conversion to 1986-’90 style pushrod tube assemblies when using adjustablepushrods. S&S kits for 1991-'03 engines include a special pushrod tube adapter.Pushrod tube assemblies are not included and must be purchased separately.Parts forVictory®2003-2013RacingProductsTools & ShopSuppliesS&S® SIDEWINDER® BIG BORE KITS for 1986-'03 Harley-Davidson® SPORTSTER® modelsDisplacement Stroke BoreCTOCompressionRatioPistonTypeCylinder LengthEngineLifeApplicationPart No.79" Sportster** 313⁄16" 35⁄8" ‡ Forged Stock Stock-like 1986 to 2003 91-3002+.437"1986 to 1990 91-312189" Sportster* 45⁄16" 35⁄8" ‡ ForgedVery good(5.087") 1991 to 2003 † 91-3123Specify Specify Specify Specify 1986-2003 † 106-5834All other Sportster & Buell® year groups must use the CTO part number.** This kit has stock height cylinders and will fit Buell® motorcycles.* Denotes kit supplied in S&S Hot Set Up Kit.‡ Compression ratio depends on cylinder head type used. If stock heads are used extensive cylinder head modifications must be performed,making compression ratios completely dependent on final combustion chamber volume.† 1991 and later engines require conversion to 1986-’90 style pushrod tube assemblies when using adjustable pushrods. S&S kits for 1991-'03engines include a special pushrod tube adapter. Pushrod tube assemblies are not included and must be purchased separately.MSRP$855.95$2,339.95$2,394.95Call for PricingDealer Services& Promo ItemsWarranty &Company PolicyOEM Cross ReferenceAppendix & IndexParts Included in S&S® SIDEWINDER® BIG BORE KITS for 1986-'03 Harley-Davidson® SPORTSTER® modelsDisplacement Stroke Kit Part No.FlywheelGasketsAssemblyPistons CylindersHeadHead MountBoltPushrods ManifoldHead BaseCenter Front79" 313⁄16" 91-3002 Forged l l l91-3121 l Forged l l l l l l l l89" * 45⁄16"91-3123 l Forged l l l l l l l l* Denotes kit supplied in S&S Hot Set Up Kit.4-10 Order toll free 866-244-2673