|
|||
| High Performance Parts for American V-Twins Since 1958 | |||
 Displacement is a way to describe how large an engine is. Cylinder bore size (diameter of the pistons), stroke (how far the piston travels), and the number of cylinders and engine has determine the displacement of the engine. Displacement can be thought of as the volume of air and fuel the engine can draw into each cylinder, multiplied by the number of cylinders. Bigger is always better!
The term stroker refers to high performance engines or engine kits that include a crankshaft or flywheels with a longer stroke than a stock engine. The longer stroke results in more displacement because the piston travels farther with each crankshaft rotation. Strokers are often coupled with big bore cylinders and pistons for even larger displacement.
The term stroke refers to the distance the piston travels in the cylinder. Longer stroke is achieved by designing a crankshaft with a greater distance from the crankpin to the connecting rod journal or crankpin. By moving farther the piston draws in a larger volume of air and fuel. The volume of air and fuel an engine can pull into the cylinders is known as displacement.
A camshaft controls the opening and closing of the intake and exhaust valves. As the camshaft rotates, eccentric lobes on the shaft push the valves open and allow them to close at the proper times, in order to allow air and fuel to be drawn into the engine and exhaust gasses to be expelled. Performance cams generally open the valves farther (lift) and keep them open longer (duration) in order to get more air in and out of the engine.
A carburetor mixes fuel in the correct proportion with air coming into the engine. It also controls engine speed, but controlling the amount of air going into the engine. A carburetor is a mechanical device that relies on air velocity and vacuum to draw fuel into the air stream. The amount of fuel is controlled by metering orifices called jets.
A throttle body on a fuel injected engine is similar to a carburetor in that it controls the amount of air going into the engine, but it does not mix fuel with the air. The amount of air allowed into the engine determines the engine speed. Fuel is sprayed under pressure into the air stream, through fuel injectors, which are generally located in the intake manifold or in some cases the intake port of the cylinder head. The amount of fuel is generally controlled by a computer.
Lift refers to how far the valve travels from the fully closed position to fully open. Valve lift is determined by the height of the lobes of the cam shaft. The ratio of the rocker arms in Harley-Davison® overhead valve engines also effects the lift of the valves. For example the valve lift of a shovelhead engine is 1.43 times the lift of the cam, while the valve lift in Evolution® and Twin Cam 88® engines is 1.63 times the lift of the cam due to differences in the rocker arm ratio. Valve lift in overhead cam and side valve (flathead) engines is the same as the cam lift since there are no rocker arms.
Duration refers to how long a valve stays open relative to crankshaft rotation. Most performance cams have more duration than stock cams. Cams with very long duration will generally make more power at higher rpm than a shorter duration cam. Short duration cams generally make more torque at lower rpm. Also, longer duration cams are better suited to higher compression engines.
The term big bore refers to engines or engine kits that contain cylinders and pistons that that are larger than stock. The increased cylinder bore coupled with a stock stroke crankshaft results in increased displacement. Big bore kits are often used with stroker crankshaft or flywheels for greater displacement
Sidewinder® is a trade mark of S&S Cycle and refers to S&S big bore cylinders. The name refers to the “don’t tread on me” rattlesnake on the original Gadsden flag, because S&S big bore cylinders were introduced in the American bicentennial year of 1976.
An S&S Hot Set Up Kit is a complete kit of carefully selected of components designed to give our customers everything they need to complete a specific high performance engine modification. All the components are designed to work together for optimum performance and to deliver the best value possible. You can spend a lot of money on performance parts, but not get the actual performance you expect if the components are not compatible. The Hot Set Up Kit is designed to prevent that by delivering the performance we promise with parts that work together
S&S offers complete engines for Harley-Davidson® big twin motorcycles with overhead valve engines from 1936 to 2006. That include motorcycles originally equipped with knucklehead, panhead, shovelhead, Evolution®, and Twin Cam 88® engines. Engines are currently not available for flathead sidevalve engines, 2006 Dyna® models, or any 2007-or later big twin models equipped with Twin Cam 96™ engines.
Fuel system upgrades can be as simple as installing a high flow air cleaner kit, or could involved as replacing a carburetor, EFI throttle body, and/or EFI module. Improved air flow is what produces the increase in power. To get the most out of an fuel system upgrade, the exhaust system should also be upgraded. That is why air cleaner/exhaust upgrades are so common.
EFI calibration is a process of changing the "fuel map" and in most cases the ignition timing table in the Electronic Fuel Injection module. The module is a computer that controls the fuel injection and ignition system. Performance modifications often require changes in EFI calibration for optimum performance and driveability. Engine modifications that increase the compression ratio generally require ignition timing changes.
Carb jetting refers to the process of selecting larger or smaller carburetor jets to achieve the correct air/fuel mixture for an engine. The jets are metering orifices that are used to control the amount of fuel delivered to and engine. Most carburetors have more than one fuel circuit to control fuel delivery in different rpm ranges, and each circuit generally has its own jet. Performance modifications often require changes in carburetor jetting for optimum performance and drivability. Engine modifications that increase the compression ratio generally require ignition timing changes.
S&S tuned induction systems use scientifically designed tuned intake tracts which feature carefully chosen lengths, diameters, and tapers. By utilizing air column inertia and carefully timed gas dynamic pressure waves, the S&S VFI Tuned Induction system rams additional air into the cylinders for increased power. The look really cool too.
The S&S teardrop air cleaner has been in use since 1975, when it was introduced with the classic Super A and later Super B carburetors. The shape of this air cleaner is in fact a registered trademark of S&S Cycle Inc. S&S air cleaners provide improved air flow for better performance.
The terms bolt-on and slip-on refer to components that are easy to install. They simply "bolt on". Many bolt on components are decorative, but S&S sells bolt on performance parts such as high flow air cleaners and tuned induction systems. The term slip-on is generally refers to mufflers that "slip on" to the stock exhaust pipes. Bolt-on and Slip-on parts can often be installed by the consumer and are considered to be less expensive than other "deep performance" parts that require the engine to be disassembled and usually require a skilled mechanic for installation.
Intake refers to the components that control air and fuel delivery to an engine. This includes air cleaners, carburetors or throttle bodies, and intake manifolds. Many aftermarket intake components offer performance increases because they are less restrictive and allow the engine to "breath" or take in more air.
EFI is an acronym for Electronic Fuel Injection. Most late model motorcycles are have fuel injected engines. Harley-Davidson discontinued carbureted engines in 2007.
High performance air cleaners can flow more air then stock air cleaners. This allows the engine to draw more air into the cylinders, resulting in more power. S&S air cleaners not only flow more air, but are very efficient at removing particles of dirt from the air going into the engine. This greatly prolongs engine life. Although race engines are often operated without and air filter, S&S does not recommend running an engine on the street without an air cleaner
Performance exhaust is probably the most common performance modification. A good performance exhaust system for the street may consist of slip-on mufflers or a complete exhaust system with pipes and mufflers. Performance exhaust systems are less restrictive than stock exhaust, which allows the engine to expel exhaust gasses more quickly and make more power. Performance exhaust systems are almost always louder than stock and may violate noise ordinances in your locality.
Cylinder heads bolt on top of the cylinders of most engines. Cylinder heads contain the combustion chamber, and in the case of overhead valve and overhead cam engines, the intake and exhaust valves and the intake and exhaust ports. Cylinder head modifications or replacements can increase the performance of an engine. Modifications are done to increase port flow and to increase compression ratio.
|
Shop OnlineBuy Apparel, Bolt-on Performance Parts, Shop Supplies and much more. 
Honda VTX 1800The new S&S teardrop air cleaner kit for 2002-2008 Honda VTX 1800 models. 
Kawasaki Vulcan 900S&S teardrop air cleaner kit for Kawasaki Vulcan 900 models is not just for show. 
106" Stroker Hot Set Up KitThe 106" kit boosted performance by 37 horsepower over stock! 
Air Cleaner Kit For Honda FuryGetting more power out of an engine boils down to getting more air into it. 
106" Top End KitDespite what some say, bigger is better, and if making something bigger is easy, that's the best!
Shop OnlineBuy Apparel, Bolt-on Performance Parts, Shop Supplies and much more. |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |