Inertia switch
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Joined: Feb 2008
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From: Okinawa, Japan
Inertia switch
Call me slow, but after 3 years of ownership, I've noticed a correlation between idle speed and movement. When I start my bike, the idle speed will stay high until I come to my first complete stop. Is there an inertia switch someplace in the electronic control unit someplace?
Inertia Switch?
I've wondered that me-self after coming off an early 60's shovel and moving to a Twin Cam, I noticed the same thing, always wandered, never thought to put it out there, Thanks for the question.
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From: SE Michigan
With a fuel injection system, the idle speed and fuel delivery is determined by many sensors, engine temp, etc, so when cold the idle is a bit higher and the fuel mixture a bit richer until it warms up.
High Idle
Thanks Keithu, makes sense now that you put it down. Helpful information as always
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From: Toronto, Ontario
It is as stated Engine Temp, the same will happen if you just sit in the Garage for sometime, once the sensors sense the engine Temp up , it will lower idle speed. something similar will happen with Carbed bikes .
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From: SE Michigan
Yes, but *it* (higher idle when cold) isnt the issue - fuel is colder and denser thus you will see 5% less MPG when its cold.
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From: Honah Lee
Short answer is no. My guess if that's your butter fly of your throttle body may be hanging. Only idle control is the IAC and I doubt that would do what you describe. There is a adjustment on the butterfly and some people think they can use it for idle but its just too crude. It should allow the butterfly to close completely without going so far as to bind. Its normally a factory setting. Be sure you pull and push cables are correctly adjusted to allow it to shut also.
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From: Western MD
The IAC is controlled by the ECM which takes voltage and ohm readings from various sensors to determine the idle speed..
never-ever-ever mess with any throttle blade stop screw adjustment on a fuel vehicle of any type. that will really f up the works..
the throttle blade should be just about closed, but not all the way.. with the eng warmed up, the ecm should basically shut the IAC off or almost off and the eng runs on the air bypassing the throttle blade. with the eng cold or under elec load the ecm commands the IAC open to allow air to bypass the throttle blade and enter the intake through a port in the throttle body or intake runner..
never-ever-ever mess with any throttle blade stop screw adjustment on a fuel vehicle of any type. that will really f up the works..
the throttle blade should be just about closed, but not all the way.. with the eng warmed up, the ecm should basically shut the IAC off or almost off and the eng runs on the air bypassing the throttle blade. with the eng cold or under elec load the ecm commands the IAC open to allow air to bypass the throttle blade and enter the intake through a port in the throttle body or intake runner..
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