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Discussion Starter #1 (Edited)
why idle rpm goes up when putting in 1st?

Hi,

Not all the time, but very recent change, it idles on neutral at let's say 1400 rpms but 2000rpm in 1st gear (while holding the clutch in both cases).

-it is not related to cold or warm engine (it did that after 45min of highway at 5000rpm)
-I suspected oxygen sensor but I have no self-diag code other than the normal 12, and the idle is smooth despite having variable rpms. Consumption didn't change.
-it's not related to throttle cables stretching or handlebar position (clutch, throttle and handlebar are not moving, just the shifter from 1st to/from neutral).

I noticed it the first time while passing gears on the rear stand.
But it did it on the ground too without turning wheels.
(2015 model, bike has over 45000 miles).
If anything, I would have thought clutch plates should have caused a minor slowdown when passing 1st, not higher rpms.

Any idea what's up?
 

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These are unrelated issues. My issue is beyond the title...which I will edit.
You obviously never clicked on the first link, as Fly-Sig said exactly what you said , this from his post ;Twice the idle has been normal until kicking it into 1st gear, then the rpms rise.

I also did a post #24 in that thread linking this one. My link with TPS settings is for reference, areas I would check, is the plug to the air temperature sensor, the connection to the engine / water temperature sensor and both main and sub-throttle sensor plugs, the first two the ECU uses a default of colder settings when it gets a bad signal, this is covered in the DFI chapter. It is not uncommon to have a corroded socket or loose connection. I was hoping Fly-Sig would chime in here.
https://www.kawasakiversys.com/forums/1017025-post11.html
 

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Hi,

Not all the time, but very recent change, it idles on neutral at let's say 1400 rpms but 2000rpm in 1st gear (while holding the clutch in both cases).

-it is not related to cold or warm engine (it did that after 45min of highway at 5000rpm)
-I suspected oxygen sensor but I have no self-diag code other than the normal 12, and the idle is smooth despite having variable rpms. Consumption didn't change.
-it's not related to throttle cables stretching or handlebar position (clutch, throttle and handlebar are not moving, just the shifter from 1st to/from neutral).

I noticed it the first time while passing gears on the rear stand.
But it did it on the ground too without turning wheels.
(2015 model, bike has over 45000 miles).
If anything, I would have thought clutch plates should have caused a minor slowdown when passing 1st, not higher rpms.

Any idea what's up?
MY '15 V650 basically does the SAME thing....
 

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Discussion Starter #6
You obviously never clicked on the first link, as Fly-Sig said exactly what you said , this from his post ;Twice the idle has been normal until kicking it into 1st gear, then the rpms rise.

https://www.kawasakiversys.com/forums/1017025-post11.html
(Thanks for clarifying the link with specific posts.)

I did click both and within few posts, the symptoms were not matching.
Post 11 was too far; seems to match 50%.

For mine, it is irrelevant if engine is warm or cold, it happens anyway (like I wrote, 45 minutes of highway).

But I can imagine the root cause could be the same. I'd like to know what it is though.

From that thread, I can't understand the diagnosis, what could have suddenly changed or what to fix if that behavior is not normal (after 3 years, I believe it's not normal).

There is mention of temp sensor, how rich/lean, thr. body position and sensors and etc... all of which I didn't touch. Heck, I don't even touch the right grip.

It's a bit reassuring that others have had that behavior (if not problem).

What puzzles me is why passing in gear rises the rpm. If any sense can be made of that, it would be good start.
 

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It's simply how it's calibrated... What mileage are you at, and have you not already vacuum synchronized your throttle bodies and inspected your valve clearances?
 

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Discussion Starter #8
It's simply how it's calibrated... What mileage are you at, and have you not already vacuum synchronized your throttle bodies and inspected your valve clearances?
I wrote that mileage is about 45000miles.
Valves were adjusted last may.
I thought throttle body sync would only affect smoothness of idle (which is smooth).
How would TBS or valves influence rpms only when shifting in gear?

My understanding is that the neutral sensor feeds also the ECU and for some reason not explained, it opens the throttle as if cold (which it isn't). So, the temperature sensor comment is making a bit of sense, but why would it be ignored when in neutral? I mean, is the ECU really having a completely different operational mode just for neutral?!! Temp sensor is certainly not ignored in neutral as we all heard the fan start or stop when idling...
 

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I wrote that mileage is about 45000miles.
Valves were adjusted last may.
I thought throttle body sync would only affect smoothness of idle (which is smooth).
How would TBS or valves influence rpms only when shifting in gear?

My understanding is that the neutral sensor feeds also the ECU and for some reason not explained, it opens the throttle as if cold (which it isn't). So, the temperature sensor comment is making a bit of sense, but why would it be ignored when in neutral? I mean, is the ECU really having a completely different operational mode just for neutral?!! Temp sensor is certainly not ignored in neutral as we all heard the fan start or stop when idling...
Okay I remember now when my 2007 does that. It's only when it's still on cold fast idle.

I assume your spark plugs were also replaced when valves were adjusted? You should definitely check and adjust throttle body vacuum synchronization, which is performed at 1,300 rpm idle. Idle speed will be even more stable and less affected once your TB's are perfectly synchronized for optimal state of tune.
 

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Discussion Starter #10
Okay I remember now when my 2007 does that. It's only when it's still on cold fast idle.

I assume your spark plugs were also replaced when valves were adjusted? You should definitely check and adjust throttle body vacuum synchronization, which is performed at 1,300 rpm idle. Idle speed will be even more stable and less affected once your TB's are perfectly synchronized for optimal state of tune.
It may be good advice but "how" does that cause rpms to go higher when I pass in gear? My question is "why/how". It is still not making any sense. :surprise:
 

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It may be good advice but "how" does that cause rpms to go higher when I pass in gear? My question is "why/how". It is still not making any sense. :surprise:
ECU is simply calibrated that way to help prevent stalling when engine is still cold.

Just vacuum synch your TB's already and it won't be so bad... You did replace your spark plugs when valves were adjusted?
 

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Well if it is any help, my 2015 did exactly that, went to 2000 RPM , at a stop light in first gear, after coming from a 2 hour ride with 80'F ambient, shortly after I pulled the various sensors, checked the main and sub TPS and also checked the ECU grounds ( which are hidden under the seat bracket ) . Never done it again. From reading the DFI chapter, several defaults are to lower temperature from actual if a malfunction on the sensor, you are correct, doing my latest Polaris regulator tests the fan cycled about 5 times over 30 minutes. I am only guessing but that increase in RPM would probably happen if you went from neutral directly to second, I assume the neutral is under a certain criteria , once you are in gear all sensors are active with the ECU , when they quite possibly were bypassed during idle.
For myself, the very first thing I do when trying to find intermittent problems is eliminate the simple. For me top of the list is frame grounds including the ECU , I think there are something like 5 frame grounds on the 2015 and 1 engine ground. Next I would pull apart all the sensors ( main and sub TPS )and make sure no corrosion then apply a small amount of dielectric grease, making sure that the plugs were well seated. The very last would be to check the engine water temp sensor connection .
 

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My 2015 no longer does this to the extreme. A higher idle when cold, yes, and it seems normal compared to all the other kinds of vehicles I've owned.

What's changed since then? I found the vacuum leak.

In my case it was the shiny thin plastic vacuum line that runs to the intake pressure sensor (not quite the exactly correct part name) which is mounted to the left side of the fuel tank under the left plastic trim. It is very near the charcoal canister. Sorry, the Kawi website parts diagrams aren't helping me today. Anyhow, there is a very thin-walled plastic line that runs to this sensor. Mine had a hidden crack new from the factory, and others have reported the same problem. Replacing it with a regular thick rubber vacuum hose solved the problem.

The sensor tells the ECU what the air pressure is inside the intake air system. The leak was causing a bad lean misfire in the 2500-3500 rpm range, which was cured with replacing the vacuum line. Since then I have never had the runaway idle problem.
 

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My 2015 no longer does this to the extreme. A higher idle when cold, yes, and it seems normal compared to all the other kinds of vehicles I've owned.

What's changed since then? I found the vacuum leak.

In my case it was the shiny thin plastic vacuum line that runs to the intake pressure sensor (not quite the exactly correct part name) which is mounted to the left side of the fuel tank under the left plastic trim. It is very near the charcoal canister. Sorry, the Kawi website parts diagrams aren't helping me today. Anyhow, there is a very thin-walled plastic line that runs to this sensor. Mine had a hidden crack new from the factory, and others have reported the same problem. Replacing it with a regular thick rubber vacuum hose solved the problem.

The sensor tells the ECU what the air pressure is inside the intake air system. The leak was causing a bad lean misfire in the 2500-3500 rpm range, which was cured with replacing the vacuum line. Since then I have never had the runaway idle problem.
I recall some mention of this in a different thread, so looks like I am going to have a look at that on my Versys.
 

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Discussion Starter #16
Interesting thread. For the record never had this problem with my 2015 650, 51000 K.
To warn the passing reader about the mingling of symptoms:
:nerd:

A fast idle (vacuum leak)?
A mildly faster idle on cold engine (normal)?
A rough or twitchy idle (throttle body unsync)?
A fast idle in gear only on warm engine? (possibly faulty sensors connections)

This thread is perhaps interesting but I certainly didn't intend for it to be a hub of tangential symptoms around idling engine... :smile2:
 

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Be careful What You Wish For

To warn the passing reader about the mingling of symptoms:
:nerd:

A fast idle (vacuum leak)?
A mildly faster idle on cold engine (normal)?
A rough or twitchy idle (throttle body unsync)?
A fast idle in gear only on warm engine? (possibly faulty sensors connections)

This thread is perhaps interesting but I certainly didn't intend for it to be a hub of tangential symptoms around idling engine... :smile2:
And yes I intend to take a look on my bike. Before this thread started I figured I was fine for the season, now I have some doubt.>:)
 

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My 2015 no longer does this to the extreme. A higher idle when cold, yes, and it seems normal compared to all the other kinds of vehicles I've owned.

What's changed since then? I found the vacuum leak.

In my case it was the shiny thin plastic vacuum line that runs to the intake pressure sensor (not quite the exactly correct part name) which is mounted to the left side of the fuel tank under the left plastic trim. It is very near the charcoal canister. Sorry, the Kawi website parts diagrams aren't helping me today. Anyhow, there is a very thin-walled plastic line that runs to this sensor. Mine had a hidden crack new from the factory, and others have reported the same problem. Replacing it with a regular thick rubber vacuum hose solved the problem.

The sensor tells the ECU what the air pressure is inside the intake air system. The leak was causing a bad lean misfire in the 2500-3500 rpm range, which was cured with replacing the vacuum line. Since then I have never had the runaway idle problem.
I got a feeling we aren't talking the same thing, this is the air pressure sensor for elevation.I did remove the hose and inspect it, notice the wall thickness, when done I routed it differently so I have more slack now. Man the left side doesn't look anything like when I bought it. FYI to the left is my thermo-bob #4 for snow bikes, coming out of the old thermostat housing, no stratification and it works flawlessly .The 90' fitting is my bypass line, the hose going straight down goes to the rad, the hose from the T Stat housing goes through the frame into the 90' inlet not visible from this angle, and the solution to my many adaptations with the original T Bob. You will see some white what is K wool to protect my auxiliary wiring, which is wire tied to the frame.




FYI it wasn't a waste of time, as I have been having problems with my hidden 12V outlet for my GPS, turns out the ground was damaged internally . So I got lucky and found these on clearance at Canadian Tire clearance $8.23 with fuse holder :https://www.canadiantire.ca/en/pdp/autotrends-12v-truck-bed-outlet-0374554p.html#srp and the one I installed in place of the vertical one, clearance $5.93 without a fuse https://www.canadiantire.ca/en/pdp/autotrends-12v-power-outlet-0374547p.html#srp

So here is my old set up, under the plastic on the left side of the bike, my Garmin GPS adapter was always a struggle to get in, plus in heavy rain, water would go into the outlet



same one that is live all the time form my stop and go compressor mounted below the battery on the left side
and at CTC for $8.23

The one I have now mounted with the tab down and the opening facing towards the gas tank, 100% easier to get the adapter in, plus no way for water to run inside

Clearance CTC $5.93

 
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