Motorcycle Intake Manifolds

The engine of your motorcycle must “breathe” properly to work efficiently. The motor “inhales” the fuel-and-air mixture and “exhales” exhaust gasses. The mixture of gasoline and air produced in the carburetor enters the engine through the intake manifold. In motors with fuel injection systems, this manifold supplies the required amount of clean, fresh air which mixes with fuel from the injector before being sucked through the intake valves into the combustion chambers. During their operation, intake manifolds, made from billet aluminum or hard, durable rubber, tend to wear due to exposure to high temperatures and vibration. Seals and gaskets deform leading to leaks.

Since the pressure in the manifold is lower than the atmospheric pressure, additional air is sucked into the manifold making the air-and-fuel mixture loo lean. As a result, the engine starts harder, it begins to choke and backfire after warming up, acceleration becomes sluggish. Engine power drops significantly. To check if the intake manifold is the reason for that, you can look for visible gaps between the manifold and carburetor at one hand, and the engine head at the other. If you don’t see any gaps there, spray some flammable contact cleaner or starting fluid in that area when the engine is idling and listen for the engine rpm. If it increases, then you have intake manifold leaks.

Sometimes these malfunctions can be fixed with the installation of new gaskets or rubber spacers. You can also try and repair the leak with a special semi-drying sealant. If your carburetor wobbles while being connected to the intake manifold or holder, or your manifold is too warped, cracked, or has tears, then it needs to be replaced. Note that you will need a torque wrench to tighten all bolts according to the required specs. In our online store, you can find a comprehensive collection of motorcycle intake manifolds by some of the most reputable manufacturing companies in the industry, such as Biker’s Choice, S&S Cycle, KOSO, K&L Supply, Outside Distributing, and many others.