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Thanks Dave nice report, if it is not too difficult to do i wonder if you do the same thing as before by disconnecting the iacv before starting the bike ( iacv is in 1050 rpm running position when the bike is switched off ) and nursing it to warm up to the point where the rpm is stable enough and taking it for a ride to see if the idle is usable without the iacv valve connected.
In other words: because it is now fixed in one ( correct ) position it cannot change idle rpm and mess with idle speed.
Ignore the check engine light flashing.
+1 on Doc; max
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(03-09-2018, 06:52 AM)Mechanix_imp Wrote: (03-08-2018, 07:14 PM)max_imp Wrote: Thanks Mech, nice video's and very surprising action on the clutch, from the video it is not clear if the switch is operating to cause the increased rpm effect, is it possible to disconnect the switch and see if any change occurs?
And has this behaviour started at the same time the low idle started?
Thanks for posting the video's they are perfect for us to work with as we are mostly in the dark about the exact behaviour since none of our team actually have the issue ourselves.
max
Ok, this morning was a bit cool so I started the bike and had it in neutral, no issue. Put bike in gear and had idle at 1200rpm until I began to let out the clutch lever...up to 1700rpm. I shut off the bike and disconnected the clutch switch, restarted bike and cold idle was 2000rpm. A few twists of the throttle and idle rpm still at 2000 and no reaction with clutch. I had to leave for work so no video to post but I will try this again on another cool morning and start off recording.
That's just crazy. Watched the video and never seen anything like that. Why would the idle go up just because the clutch is being let out? (except if you have Suzuki's easy start lol). I don't understand the relation.
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Just a guess- let the clutch out, rpms drop, system tries to regulate and over compensates because something is out of wack.
Every modern vehicle compensates something like neutral or park to drive.
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(03-09-2018, 07:58 PM)max_imp Wrote: Mechanix i think your video's are very educational but the next one can be a bit better and longer, good idea and very good of you to recognize this.
What i also wonder is if the clutch effect works in all gears and neutral or just 1st gear ( both with connected and disconnected switch ) you could comment this in the video.
I suspect this behaviour is possibly programmed into the ecm hence the gear test.
You are doing great, we can come up with enough hints to narrow this down quite a bit but we need your help and i will try to explain why things happen the way they do along the way.
cheers max
Thanks, I’m pressed for time in the cool mornings before work but I will be sure to get up early on my day off to try again.
I can tell you it happens in every gear but not in neutral, and seems to take a while to get out of the cold high idle condition...the colder it is the longer it takes. I will comment on the next video or videos with switch connected and disconnected. But I’m running out of cold days here!
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I have a 2009 CBF1000 and also 2012 CBF1000. The 2012 when you let the clutch out, RPM will increase 200 to 300 RPMs. That happens so it'll prevent it from stalling when engaging 1st gear. The 2009 CBF doesn't have that feature. I also read the last few pages on this and nobody mentioned cleaning their negative cable to the body. Sometimes corrosion gives you a lot of Gremlins. The one guy I remember that posted a few pages down changed his battery I wonder if he was able to clean the negative cable to the body so he didn't have any problems after that. The 2009 CBF is notorious for burning out stator. My preventive maintenance is to make sure that the ground cable is always clean and a battery gauge to monitor the stator output. So far, the 2009 is still running good. This thread really interests me because I have a used 2014 with 19000 Km that i'm looking at.
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I would believe this cold idle increase with clutch engagement is a FACTORY deal but it didn't do it in last year's cold days. It came around near the time the hot low idle issue showed up...about 5700 miles. I'm going to tear this thing apart after I get my truck running!
Here is a link to another high idle video...hopefully better than the last one. Temperature in the morning was 42 degrees.
https://youtu.be/J5KvMBxo-sc
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Mine has never done that, and in 5 years I don't remember anyone on the board mentioning or questioning it either. Have never read it in a road test either by the magazines either or in Honda's designer talk series. I don't think that is normal for our CB's.
Some new Suzuki's do that and they labeled it something like "easy start" or something so that newbies wouldn't stall when taking off.
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Here is a link to another high idle video...hopefully better than the last one. Temperature in the morning was 42 degrees.
https://youtu.be/J5KvMBxo-sc
My 2012 CBF1000 also does that, it's very normal. I think it's called easy start for newbies.
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Bindir. Watched the video again. Does it do it once it reaches normal idle of 1050 and you put it in gear?
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(03-12-2018, 01:57 AM)The ferret_imp Wrote: Bindir. Watched the video again. Does it do it once it reaches normal idle of 1050 and you put it in gear?
No, this issue only happens when it's cold. The other day it was around 70 degrees and it didn't happen, but it was at normal idle speed after I started it and not cold idle. I will check it out some more but I believe when the cold goes away so will the issue. I need to document all I can so when I take it in (under warranty) they can see exactly what I'm wanting fixed. I'm sure they will throw a bunch of parts on it hoping it goes away.
