Rpm . idle warm /hot

georgerdp

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Hi , I am confused badly .
Idle should stay fix at a point like 1250 or 1340 ?
Or is normal to change 1260 1340 continously ?
When engine is cold is at about 1140 -1200
Warm 1200 - 1260.
And when goes very hot is 1260 - 1340 and time to time 1200.
Is that normal ?
I have done the plug caps thing , new plugs , new oil .
Throttle body sync and the rpm do the same .
Sorry if my questions are stupid .
 
IME idle speed variations are most often due to air control (think vacuum leaks), fuel quality (cleanliness), Ignition quality but there can be other factors.

- Fuel quality and moisture content effects idle
+ Spark plug gap can play a role when fuel quality is questionable
+ Spark plug gap in excess can lead to hunting constant variation in RPM
- Vacuum leaks, hoses, TB boots
- Thermostat operating erratically, impacts IDLE AIR CONTROL VALVE (IACV), impacts idle speed.
- Dirty air being passed through IACV can lead to it being sticky or gummy.
- Valve lash impacts intake manifold vacuum and fuel distribution as well as timing. It can create a lope in the idle.
}} FSM tune tune up begins with: Valve lash adjust, TB sync, & Idle speed set.
- TB sync. More for vibration reduction than correcting varying idle speeds.

Those are the items that come to mind. Notice here the three hoses. 2 are for the IACV and are filtered air for Idle to say 3000 RPM. Notice to right are smaller hoses going forward; those are coolant hoses so the IACV can vary the idle air volume (engine speed) based upon engine coolant temperature.
picture.php


Abstract items include:
- Charging system health. Is it maintaining Stable voltage
- Bad connections to the ECM from any of the sensors
 
What you describe is how my 2006 ran when it was brand new and the same way it runs now that it has 21,000 miles! :thumbup:

The digital display may bounce around but it's interpolating the RPMS digitally so it will jump around a bit. So long as the engine sounds smooth at idle and doesn't sound like it's loping or revving up and down you are fine.
 
What you describe is how my 2006 ran when it was brand new and the same way it runs now that it has 21,000 miles! :thumbup:

The digital display may bounce around but it's interpolating the RPMS digitally so it will jump around a bit. So long as the engine sounds smooth at idle and doesn't sound like it's loping or revving up and down you are fine.

^^ mine gets a bit of lope to it on occasion but is otherwise pretty stable. From the tach it might vary a needles width (08).

Does yours change tone (rpm) or just the tach being fickle?

PS - left off the whole TPS issue.
 
^^ mine gets a bit of lope to it on occasion but is otherwise pretty stable. From the tach it might vary a needles width (08).

Does yours change tone (rpm) or just the tach being fickle?

PS - left off the whole TPS issue.

Mine does lope once in awhile, usually when restarted warm for the first 15 seconds and then it smooths right back out at around 1200 rpms.
 
Mine occasionally changes tone. I can hear it in the exhaust. But I've never had stalling or starting issues. So I can't imagine what I'm hearing is a bad sign. :thumbup:
 
Hi , I am confused badly .
Idle should stay fix at a point like 1250 or 1340 ?
Or is normal to change 1260 1340 continously ?
When engine is cold is at about 1140 -1200
Warm 1200 - 1260.
And when goes very hot is 1260 - 1340 and time to time 1200.
Is that normal ?
I have done the plug caps thing , new plugs , new oil .
Throttle body sync and the rpm do the same .
Sorry if my questions are stupid .

Nope, its not normal. When starting a cold engine, the idle should be approx 2-300 RPM's higher. Depending on how cold it is, it may be a minute, might be 2 or 3.. Once warmed up, the idle shold be (at least per the manual) approx 1,300.

Some slight variation is normal.

If its starting cold with a low idle and then rising when warm, there's an issue.

A TPS check may be in order.

Final impact as I re-call, had a thread (Randy if you have it handy) about the coolant going to / for the cold idle circuit. If this is clogged up it'll cause issues.

If the manifold block (for adjusting the throttle bodies) is crapped up (another member had that years ago, pulled it apart and cleaned it), yep, issues.

How close did you get your throttle sync in MM's?.. Did you see it or did the shop do it behind closed doors? The closer you can get the vacuum on all cylinders the better.

A strong dose of a fuel cleaner may help, depending on if its a fuel issue (certainly can't hurt)..

NOT asked, do you have a power commander, remove cats, aftermarket pipes, adjust the idle CO settings??


I have my hot idle set at about 1,100. Cold start, about 1,300. Right now during summer, high idle isn't quite a inute... If it varies 50 RPM's hot, its alot..
 
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Nope, its not normal. When starting a cold engine, the idle should be approx 2-300 RPM's higher. Depending on how cold it is, it may be a minute, might be 2 or 3.. Once warmed up, the idle shold be (at least per the manual) approx 1,300.

Some slight variation is normal.

If its starting cold with a low idle and then rising when warm, there's an issue.

A TPS check may be in order.

Final impact as I re-call, had a thread (Randy if you have it handy) about the coolant going to / for the cold idle circuit. If this is clogged up it'll cause issues.

If the manifold block (for adjusting the throttle bodies) is crapped up (another member had that years ago, pulled it apart and cleaned it), yep, issues.

How close did you get your throttle sync in MM's?.. Did you see it or did the shop do it behind closed doors? The closer you can get the vacuum on all cylinders the better.

A strong dose of a fuel cleaner may help, depending on if its a fuel issue (certainly can't hurt)..

NOT asked, do you have a power commander, remove cats, aftermarket pipes, adjust the idle CO settings??


I have my hot idle set at about 1,100. Cold start, about 1,300. Right now during summer, high idle isn't quite a inute... If it varies 50 RPM's hot, its alot..

When I said cold is after first 1-2 min when goes about 1600.

I am at work now and can't upload a video now .
I will do it in the morning at first start and you will understand
What i mean .
Thank you guys for replays .
 
I looked up some previous posts of yours and need to ask the following;

When you replaced the spark plugs, did you check or adjust the gaps(iridiums or regular)?

When you did your throttle sync, you asked about re-checking at 5,000 RPM's.

Can you elaborate on you final check/adjustment, ie, at idle 1,300 and at 4,000 RPM's, 5,000RPM's or ? And just how close did you get averaging out between the two?

Did you adjust the CENTER SCREW between the two throttle bodies at all (it adjusts the butterfly shafts to each other-has a spring on it to keep it from moving).

And probably, most importantly, do you have a little bit of throttle cable play? This is noticed pretty easily at the throttle grip but at the throttle cable cam (left side, below the tank, above the frame), there should be a little bit of up and down play. Besides checking that, turn the steering in both directions and check for and thriottle cable binding, (ie, that cam opening the throttle).

For others, this was the same bike with the whistling after the air filter BUT the bike ran good after that.
 
I looked up some previous posts of yours and need to ask the following;

When you replaced the spark plugs, did you check or adjust the gaps(iridiums or regular)?

When you did your throttle sync, you asked about re-checking at 5,000 RPM's.

Can you elaborate on you final check/adjustment, ie, at idle 1,300 and at 4,000 RPM's, 5,000RPM's or ? And just how close did you get averaging out between the two?

Did you adjust the CENTER SCREW between the two throttle bodies at all (it adjusts the butterfly shafts to each other-has a spring on it to keep it from moving).

And probably, most importantly, do you have a little bit of throttle cable play? This is noticed pretty easily at the throttle grip but at the throttle cable cam (left side, below the tank, above the frame), there should be a little bit of up and down play. Besides checking that, turn the steering in both directions and check for and thriottle cable binding, (ie, that cam opening the throttle).

For others, this was the same bike with the whistling after the air filter BUT the bike ran good after that.

At iridium spark plugs I have read on the back of the box to NOT ADJUST the gaps . So I did not .

Sync is done at idle with carbtune morgan and 4000 rpm .

I did not adjust the centre screw at all (the butterfly ) .

It is a little throttle cable play (left side, below the tank, above the frame)
as when I did buy the bike was too loose and now it is just with a little play as much as not get grip .

Here is video done this morning .

https://www.youtube.com/watch?v=sPkOX6jT3ow

The video is done from 3 parts ( 3 videos added together )

First at start 24 sec , second cold engine idle 13 sec and last warm 15 sec .
In first 24 sec the sound difference it is how I did positioned the phone .

Why I have done , plugs oil and the sync ? Because I have at 5000 5500 vibrations which are very annoying in my foot . (right foot ) . Is not strong but is annoying at after 1 Hour journey on the bike ... I feel it there .
 
Most everything above sounds good, (plugs may be an issue-see below)


Re the vibrations, check the torque on ALL FIVE of your engine mounting bolts. Theres two long steel bolts with nuts at the rear as well. I've gotten some vibration from 2 of the "arm" bolts that loosened to maybe 37 ft lbs (on their own). That little bit fixed the new vibs that developed. (dry threads, no loctite, etc). 40 ft lbs exactly on everything. A good going over won't hurt either.

The video is very helpful. Once running, your not getting more than 60 RPM's variance at any one clip. 60 RPM's is minimal and IME, very acceptable.


The video, (at least for me) is somewhat confusing. At least the middle video-temp gauge shows COLD but its idleing as if to temp. Perhaps just what your labeling each section, please read on;

If the "start" video is dead cold, 1600 RPMs is fine. The last, at temp, the RPM's are fine. The middle video its idleing down BUT the coolant appears to NOT BE AT normal operating TEMP. If the bike was just started, idles high(as earlier shown), then idled down even thou the coolant temp is still low, that's normal. (My bike after a minute or so will idle down with coolant temps at 120F)

Can you please video, if possible one long clip and try and keep the temp gauge with the rev's in the video. (That or clarify the middle section of video)

Start from dead cold, bike still running, warming up, keep it running until up to normal operating temp (don't need the fan kicking on hot.

And lastly, starting while at temp. (obviously, you have to turn it off). Should idle at your normal, lower setting..



What are your current outside temps when recording (F please..)? And how close did you get your sync(as you re-call?)


**I doubt its an issue but you can indeed adjust the iridiums. One of mine was off by .001 so I didn't mess with it. You may get a slightly smoother idle should one or two be off and adjusted CORRECTLY- your call.. Those Iridiums are not made for only the FZ obviously, so the stock, "factory gap", may very well be off...

From the NGK website; NGK Spark Plugs USA
 
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I have to ask, did you check the gap?
Even tho it says not adjust the gap, if the installed plug exceeds the gap IT MUST BE ADJUSTED TO THE PROPER GAP! Although too little you may not notice while too much could cause issues like inability to burn the mixture depending on the conditions i.e. cylinder pressure, fuel quality, AFR....
I would pull the plugs and corret that.
 
I have to ask, did you check the gap?
Even tho it says not adjust the gap, if the installed plug exceeds the gap IT MUST BE ADJUSTED TO THE PROPER GAP! Although too little you may not notice while too much could cause issues like inability to burn the mixture depending on the conditions i.e. cylinder pressure, fuel quality, AFR....
I would pull the plugs and corret that.


Post #11, plug gaps were NOT checked, just installed

For the OP, click on that link I posted, it shows you how to correctly and safely check and adjust tghe Iridiums..
 
Post #11, plug gaps were NOT checked, just installed

For the OP, click on that link I posted, it shows you how to correctly and safely check and adjust tghe Iridiums..

Wednesday I will get by post the gap tools from ebay and I will adjust the spark plugs to 0.7mm . I will let you know if is any change .
The bike run very well except 5000 5400 rpm .
If is the problem from the gap of the plugs , should not be vibrating at all Rpm ?

Here is video with full rpm progress , cold to warm engine .

https://www.youtube.com/watch?v=S5eSHl82qcA
 
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That video was much better, thanks...

The cold start high idle may be a little high, but acceptable, the rest of it normal short of the end.

When you revved it, seconds later (just about at the end), the temp gauge dropped down.

**The water pump is pumping more volume with more rev's, that may be the reason however mine doing that(while stationary, revving), will increase the temp, NOT drop.**

How many temp bars did it normally run at, normal running about?
A bit higher than shown in that video? (S1 owners, PLEASE CHIME IN).

When was the coolant last changed out?

IF the temp gauge was running a bit higher normally(before issues), and is making wide swings in the temp, I'd be leaning towards the thermostat being stuck open.

The video, somewhat confirms this. Cold start, high rev's for about a minute(normal), the rev's drop(normal), the temp gauge eventually shows one bar(normal).

When you rev it, the temp drops, not normal... Back to the above **'s ^^. If the thermostat is stuck open, the extra rev's is allowing the coolant to flow and cool the engine quickly vs REGULATING the amount of flow thru the thermostat..

The thermostat should keep the temps from jumping about, gradually rising and lowering depending on the riding conditions.

The FSM shows thermostat replacment requiring throttle body removal, etc. One member was able to change his out his thermostat strictly by working under the TB's and not removing anything else(short of the hose). It was tight but doable.

Did you check the frame to engine mounting bolts?

You are getting a little more RPM variation in tha video. You may want to run a couple of tanks of Chevron Techtron fuel system cleaner (on the heavy side), it may help smooth things out a little.

Re 5000, 5400 RPM's, what is happening? While riding, with some load on the engine, misfire or ?


Another possibility but NOT likely (from what I'm seeing) is the temp switch in the engine itself. It can be tested electronically:
Part #20; Yamaha Motorcycle Parts 2005 FZ6 - FZ6ST ELECTRICAL 1 Diagram

Randy, your thoughts? [MENTION=15974]FinalImpact[/MENTION]

Double click to enlarge;
 
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In city 3 lines temp and motorway 2 lines all the time , this are temp I am running at .

5000 5400 is where my bike has the vibrations on right foot .
 
In city 3 lines temp and motorway 2 lines all the time , this are temp I am running at .

5000 5400 is where my bike has the vibrations on right foot .

Are the temps (3 or 2 bars current) and what you were getting normally or is it showing just one bar NOW (with the issue)?


And did you re-check the torque on the engine mounts, sub frame(specifically the lower bottom, where it bolts to the main frame), etc?
 
Are the temps (3 or 2 bars current) and what you were getting normally or is it showing just one bar NOW (with the issue)?


And did you re-check the torque on the engine mounts, sub frame(specifically the lower bottom, where it bolts to the main frame), etc?

temperature is ok and was the same for last 1400 miles since I have the bike .
I did not re-checked the torque on the engine mounts as I do not have the right wrench yet.
 
temperature is ok and was the same for last 1400 miles since I have the bike .
I did not re-checked the torque on the engine mounts as I do not have the right wrench yet.

Ok.

Try to get the most accurate wrench you can (preferably max torque on the wrench 80-100 ft lbs), so your 40 ft lbs is about in the middle(dry threads BTW).

I suspect something has loosened up slightly. And check the lower sub frame bolt (to the frame) too when you can..
 
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