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Just noticed this hanging behind the air cleaner. It's capped off so I am sure it's fine and likely for something my bike just doesn't have. Does anyone know what it is for though?
That little guy is clipped to the OEM air intake box. Its not plugged in it, but just clipped to it. I think its there for emission reasons? Anyways, its worthless. Just zip-tie it up behind your air filter; that's what most do.
The HDI (International) bikes have an active exhaust system to meet, I think, European noise requirements. On my Fatbob the original lower muffler had a small baffle and upper a large baffle. The upper pipe also had an electrically operated valve that was closed at lower throttle openings. This forced all of the exhaust through the lower, smaller baffle for reduced noise. When the throttle was opened, the valve opened to allow the increased exhaust flow to exit via both mufflers. The air filter inlet is fitted with a solenoid operated gate valve. The gate valve is also closed at low power and open at high power. This is an attempt to match the incoming and outgoing airflow. Both valves are controlled by the ECM.
The plug you show is for this gate valve.
I have swapped the original pipes for Rush slip-ons, and have had the exhaust valve locked open.
My Fatbob now sounds like a Harley should, even when idling. And, as a bonus, I don't have to wring it's neck to get it to go. Heaps more torque to go along with the extra sound.
Colin.
Originally Posted by rcaddell
Figured it was an emissions thing ... what does it do for the overseas bike? Out of curiosity.
Developed by Harley-Davidson Motor Co. to reduce sound and noise emissions produced by their line of motorcycles, the Active Intake Control (AIC) system is an electronically controlled servo that opens and closes a valve in the intake chamber according to preset engine speeds. The Active Intake Control works together with the Active Exhaust Control system.
Emissions Requirements
Working in accordance to meet higher emissions standards introduced by the European Commission and the Association des Constructeurs Europeens de Motocycles (ACEM) in 2008, Harley-Davidson began to implement the Active Intake Control and the Active Exhaust Control systems in their international motorcycle models.
Function
The purpose of the Active Intake System (AIS) is to lower the amount of sound, or noise, emitted by the motorcycle by regulating the intake of air into the motor. The AIS is composed of a valve and a servo that is controlled by the motorcycle's Electronic Control Module (ECM).
Operation
At idle, the AIS valve is closed, restricting the amount of air allowed into the motor to a minimum and lowering the sound levels of the exhaust. As the engine speed increases, the ECM sends a signal to the servo, which opens the valve and allows more air into the motor to meet the required air/fuel ratio for higher performance demands.
Benefits
Harley-Davidson's motorcycles have benefited from the introduction of the AIC system, in conjunction with the Active Exhaust Control system, by reducing the amount of audible and gaseous emissions to create a more environmentally sound source of transportation.
Bypassing the AIC
Although most motorcyclists may not notice the presence of the Active Intake Control, many performance-minded riders have noted that the restrictive intake may rob the motor of power. To combat this, the AIC may be bypassed with aftermarket "emulators." Doing so, however, will void the manufacturer's warranty and is intended only for off-road riding.
These are the cheapest eliminators which lie electronics that AIS continues to work.
For those of us who have a SERT there is an option to turn on or off the active intake. Active exhaust can also be turned off (always open) in the SERT, but not on. Once turned off, it stays off. Maybe a dealer download can turn it on again. Wish I could find a way to operate it with a switch... close and open the walve whenever I want to.
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