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I was pulling out from a stop the other day, slipped the clutch and holding the front brake a bit (cuz the DB in front of me couldn't decide to turn or go straight) when I noticed I really liked the tone of my pipes. More of a deep rumble than the usual thump thumpa. My idle speed was down to about 900/920 RPMs from the factory 1050 or so. My question is...Can the idle speed be adjusted down on an EFI? and if so how?

I might as well give it a shot if it can be done, 17 degrees and icy roads in Dallas all week will give me some garage time...thanks in advance for the response.
 

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Agree. It can be done, but is it really worth it? You need a certain RPM for charging and oil circulation. Plus on some 07s, maybe later, they were bumping it up cause of stalling issues.

950 probably wouldn't hurt you, but is it really worth it?
 

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I was pulling out from a stop the other day, slipped the clutch and holding the front brake a bit (cuz the DB in front of me couldn't decide to turn or go straight) when I noticed I really liked the tone of my pipes. More of a deep rumble than the usual thump thumpa. My idle speed was down to about 900/920 RPMs from the factory 1050 or so.
I'm guessing that the tone of your pipes sounded different to you because you were putting a little load on the engine by slipping the clutch?
That would make it sound deeper .... as opposed to just lowering the idle speed. Just sayin' ........
 

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Not recommended to lower your idle to the level you want... The EFI systems needs a minimum voltage to operate correctly and if you lug the motor with to slow of idle, you won't have proper oiling and it is hard on your bottomend bearings... TC motors need to idle at 1100 rpms...
 

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Idle

Some of the twin cam's oiling circuits are so narrow, they need a high flow rate as an aid in keeping them cleaned out. It is recommended to use caution for this reason as well, when making idle adjustments lower than recommended minimum specs.
 

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Discussion Starter #8
Thanks for all of the answers...

I knew if I asked the smartest forum on the web, I would get good answers. I guess I had best leave well enough alone. Besides, how much time do you really spend at an idle??? Thanks again guys...
 

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Idle speed adjusting.

I run a Thundermax on my 06 Streetglide. I have been having stalling issues on start up. My idle was set at 976 rpm. Factory manual says 950-1050rpm. I bumped it up to 1008 and still had some coughing and spitting and then it would stall. I raised it to 1024rpm and that seems to be pretty good. I am trying everything I can to keep the heat down and not waste fuel. Anyone have any good ideas it would be appreciated.
Later:coffee:
 

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I run a Thundermax on my 06 Streetglide. I have been having stalling issues on start up. My idle was set at 976 rpm. Factory manual says 950-1050rpm. I bumped it up to 1008 and still had some coughing and spitting and then it would stall. I raised it to 1024rpm and that seems to be pretty good. I am trying everything I can to keep the heat down and not waste fuel. Anyone have any good ideas it would be appreciated.
Later:coffee:
Find someone who can properly tune that mutha.
 

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I was pulling out from a stop the other day, slipped the clutch and holding the front brake a bit (cuz the DB in front of me couldn't decide to turn or go straight) when I noticed I really liked the tone of my pipes. More of a deep rumble than the usual thump thumpa. My idle speed was down to about 900/920 RPMs from the factory 1050 or so. My question is...Can the idle speed be adjusted down on an EFI? and if so how?
You will need a SERT (Screamin Eagle Race/Super Tuner) to tune the idle RPM. From the SE training video, many examples from the SE team showing idle RPMs set at 900 (at normal temperature 180 and up). I tuned my bike to 800 RPM and it sounds awesome (SE exhaust) with crisp deep exhaust notes. If at low RPM, your bike produces uneven sound levels, your AFR (Air Fuel Ratio) is either too rich or too lean for idle. You cannot just simply lower the RPM, you will need to tune the idle RPM. I spoke to a mechanic at Harley, he said he hasn't seen any official document regarding engine harm at lower RPMs. In fact, by design, the ECM lowers the RPM at higher temperature at idle to help reduce the engine heat. Also, for a bike with EFI, there is a low oil pressure warning light that warns you on low oil pressure. Typically, at idle oil pressure is 7psi to 12psi. Oil pressure lower than 5psi will trigger the warning light. At 800RPM, oil pressure is around 9psi. So as long as you don't get your warning light on, your RPM is good. I have been at many Harley events. About 20% of Harley bikers tune their bikes for performance and sound (more difficult and the fun of a Harley ownership), about 50% tune their bikes only for performance (easier) and the remain 30% ride their bikes as is, any upgrade is for the look only (this is not tuning). Below is a section about Idle RPM tuning from official Harley Davidson SE manual (version 2011). The idle RPM can be set to the lowest value (the SE Super Tuner allows 800 RPM as the lowest value for EFI, you cannot set lower) or as slow as the engine is not dying. Below is the "Idle RPM" section from the manual:

Idle RPM
Use this Tuning Table to set idle RPM to desired setting and to correct idle-related problems.
• If engine idle speed seems too low or engine occasionally dies, increase Idle RPM cells in appropriate engine temperature to correct.
• If engine idle speed seems too high, decrease Idle RPM cells in appropriate engine temperature to correct.
 

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After a new oil pump was put into my FLHTCI it would run very rough at 900 rpm idle. I took it to the dealer and they turned the idle up to 1000 rpm. That stopped it running so rough, but now it feels like it's idling too fast. Any thoughts?
 

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Thanks for breathing life into this old zombie thread so you could introduce yourself. Spend a couple of minutes reading the rules, FAQ, etc. Welcome to the forum.
 
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