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So I have had this bike for over a month and today I started having an issue out of it where the RPMS would stay at 3000 rpms in first gear. Immediately I assumed there was an idle issue, but upon further inspection I noticed that if I put it in neutral it goes back to normal RPMs. Pulling the clutch does nothing, but actually leaving 1st gear it goes to normal operating RPMs. If I am not mistaken doesn't the power commander have the ability to map out individual gears?

Anyone ever had this issue?
 

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It's not your PCV, disconnect it from the ECM and restart your grom if it does the same stuff as before do the reset ECM, TPS, and clear memory
 

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Is it just me or is there suddenly a rash of people with idle 'issues' related to the clutch lever switch? Because this sounds exactly like the clutch lever switch having gotten disconnected.
 

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The ECU uses the clutch lever switch as another neutral switch. If the lever is depressed (and not in neutral), it will drop to idle speed, just like being in neutral.
 

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The ECU uses the clutch lever switch as another neutral switch. If the lever is depressed (and not in neutral), it will drop to idle speed, just like being in neutral.
The ECU, that is where the problem is located.

You can test the clutch lever switch by disconnecting the wire and shorting it and see if there is a change in the idle if it changes the ECM is working ok, now connect the wires back up to the clutch lever and press in the clutch lever and if the idle changes than the lever and the clutch wiring circuit is working and it is back to the ECM or the ECM wire connection.
 

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the ecu uses the clutch lever switch as another neutral switch. If the lever is depressed (and not in neutral), it will drop to idle speed, just like being in neutral.
the ecu, that is where the problem is located.

You can test the clutch lever switch by disconnecting the wire and shorting it and see if there is a change in the idle if it changes the ecm is working ok, now connect the wires back up to the clutch lever and press in the clutch lever and if the idle changes than the lever and the clutch wiring circuit is working and it is back to the ecm or the ecm wire connection.

lololol.....

Seriously guys. the ECU can not decern between the clutch, sidestand and neutral.... just have a look at the wiring diagram for christ sake.

the ECU 100% DOES NOT change idle speed if its in neutral / clutch in / clutch out. HOW THE FUCK CAN IT??? 1. again, the ecu cant make out the difference between sidestand / clutch. 2. the ECU has NO POSSIBLE WAY to control idle speed. The high idle valve is ONLY used for cold starting and is NOT an idle air control valve with finite control... the high idle valve is ON or OFF, nothing in between. The ECU has NO way to partially open throttle at idle. This is why we have 1. the idle air mixture screw for fine tuning of idle, and 2. the throttle stop screw on the throttle body....

So stop spreading this shit that the clutch position and ecu changes idle up and down because there is simply no possible way for it to do so.

clutch.png
 

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Thats it, exactly there. The green and red are hooked into the neutral switch (on the shift cylinder). The magic happens in the diode shown off the image.

yup. Shoot me a pm and ill get my info to you.

Quick video of it.

The jump in rpm to ~2k is from the neutral switch in the lever being engaged/disengaged, so listen to it when its at the higher rpm, and then as i let off the clutch, you can hear (and see) it start to drop and drag. Im trying my best to let only the bike do it, but i didnt want to roll into the wall in front of me.

I guess i should have shown where the resting position is too. brb.
You can clearly see it happening here.

Lemme go lift the rear wheel off and get a video with it on/off, not an intermediary clutch position (basically let out) as in the video tho.
 

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and with the rear tire off the ground...

First it is in neutral, and i pull the lever in and out.
then we put it in gear and pull the lever. Youll see when its let out, it revs up, because its in gear but because the clutch is pulled. When the lever is pulled, the ecu thinks its in neutral (because, well... it is, just not the actual gears).

The cluster doesnt light up because the cluster is only for the actual neutral gear, otherwise it'd light up every time you went to shift, and may be hella confusing sitting at a stoplight. Am i in neutral? is it because i have the clutch pulled? Of course, you cant let the clutch out to see if its actually in neutral or if the lever is causing it because what if its not actually in neutral? The grom would jerk forward a bit and die.


So, consider the following.

Well, actually consider the previously stated.
 

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FYI the diode is there so that the neutral light works as it should and isnt always lit. If the diode was not there the positive out of the dash for the neutral light (that gets grounded by the neutral switch to complete the circuit and light up the neutral light in normal operation) would feed through the clutch switch to the side stand switch that is grounded when the sidestand is up, thus lighting up the neutral light if the bike was in gear and the clutch was out.

either way Interesting. I still dont see how it could possibly increase the idle that much without being able to control an air opening to the motor (idle air control valve).


Almost makes me want to throw my stock ecu back on my bike to see if its actually true..... i NEVER noticed this when i was running the stock ecu and im almost certain i would of if it did it.
 

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:)

Not sure how noticeable it is in the video, but the AFRs do change, however after a few seconds it stabilizes back to stoich. I don't see why it couldn't be opening the idle air.
Between the 3 wires/switches there are a few different possibilities.

neutral grounded and sidestand down -- neutral
neutral open (in gear) and sidestand down -- kill
-- (makes no difference if clutch is pulled -- diode prevents this, iirc)
neutral open, sidestand up, clutch pulled -- neutral
neutral open, sidestand up, no clutch -- gear.

from quick glance, it looks can detect if the lever is pulled by checking between the sidestand switch and the neutral wire.

Anyway, you didn't notice it because at a stoplight you pulled your clutch lever in and it fell. But as you let off the clutch, you added gas and started moving. If you had lifted the wheel off the ground, it would be apparent.
Or if you pulled the clutch in, but played around with the switch/wires you would have seen it too.
Mainly it went unnoticed because Honda did such a good job with their controls and feedback that you never would have thought about it.
 

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ACtually, I thought about the idle air comment while laying in bed and... well... that thing is always open, right? So that cant be right. Its the cold start that opens and closes.

Im sure the idle air circuit is plenty large enough to supply air for it to idle at 3000 rpm, but it seems like it.

125ccs*3000 rpm / 2 revs/bang = 187.5 liters/min = 49.5 gal/min = .83 gal/sec...
actually, that seems like a lot. Youd have to factor in the volumetric efficiency, which at that state might be pretty low, maybe even less than 70%. Buuut... a low volumetric efficiency at that point (because its being restricted by the tbody) might just be helping it out allow for the 3k idle without any air changes.

Might have to get out the meter and see if its flipping the cold start solenoid or something.
 

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ACtually, I thought about the idle air comment while laying in bed and... well... that thing is always open, right? So that cant be right. Its the cold start that opens and closes.

Im sure the idle air circuit is plenty large enough to supply air for it to idle at 3000 rpm, but it seems like it.

125ccs*3000 rpm / 2 revs/bang = 187.5 liters/min = 49.5 gal/min = .83 gal/sec...
actually, that seems like a lot. Youd have to factor in the volumetric efficiency, which at that state might be pretty low, maybe even less than 70%. Buuut... a low volumetric efficiency at that point (because its being restricted by the tbody) might just be helping it out allow for the 3k idle without any air changes.

Might have to get out the meter and see if its flipping the cold start solenoid or something.

definitely not turning the cold start on and off, you can hear that sucker click on and off real easy.

Also the idle air screw is set for the current idle RPMS, it does not open more so it cant flow more air for the higher idle.
 

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Discussion Starter #16
I followed the procedure for a reset and everything is fine now! BTW the problem didn't seem care about the lever switch. I could be IN first with the lever pulled, and click the gear into neutral and it would drop RPM, then WHILE the lever is STILL pulled drop it into first again it would shoot up to 3k. Never even releasing the lever. Never tried it with the wheel in the air banging the gears, but the problem is fixed so I'm happy! Thanks for the input guys
 

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lololol.....

Seriously guys. the ECU can not decern between the clutch, sidestand and neutral.... just have a look at the wiring diagram for christ sake.

the ECU 100% DOES NOT change idle speed if its in neutral / clutch in / clutch out. HOW THE FUCK CAN IT??? 1. again, the ecu cant make out the difference between sidestand / clutch. 2. the ECU has NO POSSIBLE WAY to control idle speed. The high idle valve is ONLY used for cold starting and is NOT an idle air control valve with finite control... the high idle valve is ON or OFF, nothing in between. The ECU has NO way to partially open throttle at idle. This is why we have 1. the idle air mixture screw for fine tuning of idle, and 2. the throttle stop screw on the throttle body....

So stop spreading this shit that the clutch position and ecu changes idle up and down because there is simply no possible way for it to do so.

View attachment 55401

Makes sense. I am thinking about putting on an aftermarket clutch perch and bridging the clutch switch wires. Must be fine to do since so many folks run this bike that way.

Thanks for the post!
 
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