idle rpm
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Cruiser
Joined: Nov 2007
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From: south coast nsw Australia
idle rpm
After some advice on my 07 Streetbob, when changing down gears and coming to a stop sometimes my engine doesnt go down to correct idle straight away ie in the lower gears with thottle off there is still some rpm above idle and when coming to a stop I need to pull the clutch on early, once stopped with the clutch in the engine settles to correct rpm after 10 secs or so, any ideas out there??
Outstanding HDF Member
Joined: Mar 2008
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From: Southwest OHIO
well i have heard if you cycle your ignition switch it will reset your idle, maybe only on a stock ecm (no tuner), but i dont know if it will work with a tuner.
they say you turn your kill switch to the on position, then turn your key to on/start. wait 10 seconds then turn it off, wait 10 more seconds and turn it on... do this 4-6 times and this should reset your zero throttle... at least thats how the baggers do it on their 96's...
i've also heard that if you dont let your bike idle down all the way before shutting/turning it off then it will idle higher on restart...
another option is that your idle sensor is dirty... if you have a shop manual look up idle air sensor, or something to that effect. its this little sensor just behind the air filter on the top of the air inlet, before the butterfly... i cleaned mine as i was haveing idleing issues, it did have a layer os sut, carbon, oil, something black on it... it was wanting to die on me... dont know if this solved my problem as its been mighty cold here the last few days...
they say you turn your kill switch to the on position, then turn your key to on/start. wait 10 seconds then turn it off, wait 10 more seconds and turn it on... do this 4-6 times and this should reset your zero throttle... at least thats how the baggers do it on their 96's...
i've also heard that if you dont let your bike idle down all the way before shutting/turning it off then it will idle higher on restart...
another option is that your idle sensor is dirty... if you have a shop manual look up idle air sensor, or something to that effect. its this little sensor just behind the air filter on the top of the air inlet, before the butterfly... i cleaned mine as i was haveing idleing issues, it did have a layer os sut, carbon, oil, something black on it... it was wanting to die on me... dont know if this solved my problem as its been mighty cold here the last few days...
Road Master
Joined: May 2006
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From:
another option is that your idle sensor is dirty... if you have a shop manual look up idle air sensor, or something to that effect. its this little sensor just behind the air filter on the top of the air inlet, before the butterfly... i cleaned mine as i was haveing idleing issues, it did have a layer os sut, carbon, oil, something black on it... it was wanting to die on me... dont know if this solved my problem as its been mighty cold here the last few days...
Is it warmed up or cold when it does this? The cold charts also raise idle rpms. And if the throttle blade wasn't closed when started it can throw off the idle air control for a short time, usually when idle returns to normal it is good there after.
Anyway good luck
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Joined: Mar 2008
Posts: 2,062
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From: Southwest OHIO
He is talking about the idle air control (IAC). It is a valve that allows air to pass in a controlled manor, or should be anyway. They have a tendancy to gum up and not move freely after awhile. Especially if the crank case breather is venting into the intake unfiltered.
Is it warmed up or cold when it does this? The cold charts also raise idle rpms. And if the throttle blade wasn't closed when started it can throw off the idle air control for a short time, usually when idle returns to normal it is good there after.
Anyway good luck
Is it warmed up or cold when it does this? The cold charts also raise idle rpms. And if the throttle blade wasn't closed when started it can throw off the idle air control for a short time, usually when idle returns to normal it is good there after.
Anyway good luck
i take it that you've done this before... if so, will spraying some carb/choke cleaner in there clean it up enough, or should i remove it and clean it. yes IAC... thats the ticket! i knew someone must know the correct name for that "thingy"
Road Master
Joined: Jul 2005
Posts: 916
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From: Mauldin, SC
My '07 did that when it was new, so I doubt the IAC was gummed up. Didn't do it every time, but quite often. This is actually a fairly common complaint.
I have a Race Tuner, so I looked at throttle position voltage and IAC position when it was idling. TPS voltage was 0.55 and IAC position was 15-18 steps. I had read several places about it being desirable for TPS voltage to be close to 0.4 and IAC steps to be close to 40, so I adjusted the throttle stop screw (the tamperproof torx) til I got 0.41 volts from the TPS and the IAC went up to 38-40 steps.
I'm not suggesting you do this, but mine has acted normal ever since I adjusted the screw 18 months ago. In order for me to get 0.41 volts from the TPS, I had to back the screw out until the butterfly was completely closed...couldn't get any lower than 0.41 volts.
I have a Race Tuner, so I looked at throttle position voltage and IAC position when it was idling. TPS voltage was 0.55 and IAC position was 15-18 steps. I had read several places about it being desirable for TPS voltage to be close to 0.4 and IAC steps to be close to 40, so I adjusted the throttle stop screw (the tamperproof torx) til I got 0.41 volts from the TPS and the IAC went up to 38-40 steps.
I'm not suggesting you do this, but mine has acted normal ever since I adjusted the screw 18 months ago. In order for me to get 0.41 volts from the TPS, I had to back the screw out until the butterfly was completely closed...couldn't get any lower than 0.41 volts.
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Cruiser
Joined: Nov 2007
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From: south coast nsw Australia
idle rpm
Thanks for replies, I'll check my IAC and see if it's dirty, thanks murphdog for your advice too, will resort to that if I cant find anything wrong with the IAC. Bike is warm when this happens, as said, happens often but not all the time, a pain in the **** really, especially at traffic lights ect I'm coming to a stop at to higher rpm and need to pull the clutch in earlier than normal.
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