2008 Fz6 CO adjustment Leo Vince how to find the best values?

Ital

Member
Hi All,
I got the Leo Vince installed installed about a year ago and right away at the dealer I immediately had them do the CO adjustment mod and had them set both co values to 24 however the bike was running way to rich and I lowered it to 14.
I think the bike runs good, but I feel at low RPM it is still a bit rich, when I tried to lower down to 9 it did not run good, it would bog down a bit when trying to accelerate at low RPMs, do you guys think that was because it was running to lean?
Just wondering what is your guys experience to get this down to just perfect? Should I keep these values always in sync?
The dealer did this the first time for me so I am not sure what were the stock values, but from what I read other 2008 were both set to zero.
 

TownsendsFJR1300

2007 FZ6
Site Supporter
Most of the factory values are different between cylinders.

I have open Scorps and never touched the CO settings(don't even know what they are). I don't have any issues(loping, richness, etc).


*I suspect at this point, W/O having the stock settings, your going to have to experiment with the settings until you find the sweet spot.
 

FinalImpact

2 Da Street, Knobs R Gone
Super Moderator
Site Supporter
Put the CO values back to where it runs best >14 ?? and
then set your idle speed to say 1300rpm. Confirm you can obtain 1600 to 900 rpm change. i.e. is it in the middle of of its travel??? Return to 1300 rpm.

Now take those 4 sync screws and for example turn them all equally in/out 1/2 to one turn.

At 1300 rpm you should get roughly 220mmHg / 8.6inHg of vacuum.

If you can get that close AND retain idle speed control, i.e. the thumb screw still moves idle above 1300 and below 1300, you should be good.


Too lean and they get slugish and can stall when coming down from RPM. With no cats at that vacuum setting it may stink a little. IIRC that equates to about 12.5:1 AFR which is rich compared to say 14.7:1 where the cats can burn more efficiently.

Buried in a post somewhere are values of AFR to CO value. Not the gauge cluster CO.

Let us know how it goes.
 

Ital

Member
Put the CO values back to where it runs best >14 ?? and
then set your idle speed to say 1300rpm. Confirm you can obtain 1600 to 900 rpm change. i.e. is it in the middle of of its travel??? Return to 1300 rpm.

Now take those 4 sync screws and for example turn them all equally in/out 1/2 to one turn.

At 1300 rpm you should get roughly 220mmHg / 8.6inHg of vacuum.

If you can get that close AND retain idle speed control, i.e. the thumb screw still moves idle above 1300 and below 1300, you should be good.


Too lean and they get slugish and can stall when coming down from RPM. With no cats at that vacuum setting it may stink a little. IIRC that equates to about 12.5:1 AFR which is rich compared to say 14.7:1 where the cats can burn more efficiently.

Buried in a post somewhere are values of AFR to CO value. Not the gauge cluster CO.

Let us know how it goes.
Thank you Finallimpact, I think this is a bit over my head.. hahaha
I goggled what are the fz6 4 sync screws and I could adjust the throttle body, but then I have no clue where or how to check "the 1300 rpm you should get roughly 220mmHg / 8.6inHg of vacuum"
 

FinalImpact

2 Da Street, Knobs R Gone
Super Moderator
Site Supporter
Sync screws are under the tank.
You need a vacuum gauge, some hose and suitable "T" to connect the vacuum gauge to sensor by the TB.





Sensor is on the right.
 

FinalImpact

2 Da Street, Knobs R Gone
Super Moderator
Site Supporter
Or just tune by ear. Turn all screws equal amounts until its better! Blah!
 

Senior

My brother is Junior
The CO settings are set specific to each bike at factory.

The FZ6 has 2 settings
C1 controlling cyclinder 1&4 and
C2 controlling cylinders 2&3

I had a fiddle and increased the set values by a small amount by adding a uniform 15 to both (I'm sure it does go up past 100 from memory).

Note that C2 (controlling the inboard cyclinders 2&3) is set higher than C1, anecdotally this would appear to be desirable to have slightly more fuel to aid cylinder cooling [emoji848]

I did this change about 7000 miles ago (I'm now at 57000 miles and have had the FZ6 since Nov2008).

Has it made the bike into a rocket ship - No. It's actually made a slight improvement in miles per gallon, maybe i don't need to open the throttle so hard, it definitely doesn't bog down when accelerating in a higher gear.

But what it has done is made it easier to cruise in 6th gear at high motorway speeds, where as before i was constantly changing between 6th and 5th.

Before
C1 -3
C2 8

After
C1 12
C2 23

20181229_121054.jpg

Sent from my SM-G950F using Tapatalk
 

Ital

Member
The CO settings are set specific to each bike at factory.

The FZ6 has 2 settings
C1 controlling cyclinder 1&4 and
C2 controlling cylinders 2&3

I had a fiddle and increased the set values by a small amount by adding a uniform 15 to both (I'm sure it does go up past 100 from memory).

Note that C2 (controlling the inboard cyclinders 2&3) is set higher than C1, anecdotally this would appear to be desirable to have slightly more fuel to aid cylinder cooling [emoji848]

I did this change about 7000 miles ago (I'm now at 57000 miles and have had the FZ6 since Nov2008).

Has it made the bike into a rocket ship - No. It's actually made a slight improvement in miles per gallon, maybe i don't need to open the throttle so hard, it definitely doesn't bog down when accelerating in a higher gear.

But what it has done is made it easier to cruise in 6th gear at high motorway speeds, where as before i was constantly changing between 6th and 5th.

Before
C1 -3
C2 8

After
C1 12
C2 23

View attachment 69769

Sent from my SM-G950F using Tapatalk
Thanks for the input, from what I read I found that all 2008 s2 have a default setting of both zero. I hope mine was as well.
where as the s1 seem to be all over the place in values. I just change mine to +14 as well. Hopefully it wont rain tomorrow and I can try those setting out. I've been riding with +19 and the bike pulls very strong, only issue I have is at idle it is not very smooth, but it could be that i need to adjust the throttle body.
Also when the bike is cold if I try to give it gas fast it wont rev up, like it is getting to much fuel, but I am guessing that is normal. It was odd that the mechanic at the dealer was telling me that was not normal and it was running rich... i dunno as I don't have a lot of experience, but when it is fully warm it revs right up with no hesitation.
 

TownsendsFJR1300

2007 FZ6
Site Supporter
Thanks for the input, from what I read I found that all 2008 s2 have a default setting of both zero. I hope mine was as well.
where as the s1 seem to be all over the place in values. I just change mine to +14 as well. Hopefully it wont rain tomorrow and I can try those setting out. I've been riding with +19 and the bike pulls very strong, only issue I have is at idle it is not very smooth, but it could be that i need to adjust the throttle body.
Also when the bike is cold if I try to give it gas fast it wont rev up, like it is getting to much fuel, but I am guessing that is normal. It was odd that the mechanic at the dealer was telling me that was not normal and it was running rich....
That mechanic is correct, it should NOT load up when cold and rev normally.

When cold, the revs (as you likely know) are slightly higher and the engine sounds different (richer)



Here's a video of mine (made to show charging voltages) on a COLD start.

NOTE, I keep my regular idle at 1,100 on purpose (the cold idle will be lower as well):

https://www.flickr.com/photos/[email protected]/29303851750/
 

Ital

Member
That mechanic is correct, it should NOT load up when cold and rev normally.

When cold, the revs (as you likely know) are slightly higher and the engine sounds different (richer)



Here's a video of mine (made to show charging voltages) on a COLD start.

NOTE, I keep my regular idle at 1,100 on purpose (the cold idle will be lower as well):

https://www.flickr.com/photos/[email protected]/29303851750/
Thank you FJR, that is helpful. Are you able to see what is your CO is set too? Since your bike is an S2 I am wondering if both setting are set to 0
My bike was bugging down cold when you GUN it.. if you rev it like you did in the video it is fine as well.
That said I did go from +19 to +14 and the bike runs a bit smoother and idles better, did not try to GUN it (for a split second) cold but that will be my next test, but overall I think I am happy with the +14

+14 noticed\changes compared to +19
* Smoother idle with very little fluctuations
* Less Vibrations while cruising
* Not as loud
* Bike seems more responsive with less gas
* Feels a bit less powerful\less torque
* When downshifting I noticed less gear drag, meaning the bike does not slow down has hard when downshifting

I have my Revs at about 1,250 I am sure I can lower it some now. I had it set higher to try to smooth it out. I will adjust the revs and perhaps do a video of a cold start in the next coming days, once I find it running right. Thanks!
 

TownsendsFJR1300

2007 FZ6
Site Supporter
I found at 1100, the bike idles smoother, more engine braking, less clunking into first (from neutral), no more than 50RPM movement tops...

I don't rev the engine while cold (and I'm in SW Florida) , there's no reason to. Back the bike out of the garage while cranking up, put on my helmet, gloves, etc, roll down the driveway, drop in gear while rolling and go. It doesn't go over 4,000 RPMs till fully warm, engine cases warm(IE oil is warm).

As for my CO #'s. I have no idea, never checked. Everything is stock (no fuel add on's, etc) except for my open Scorps (as in the video). Ran like a top with that mod, no need to touch it.

On the FJR, none of the FOUR separate throttle bodies have the same CO # from the factory. And I've never heard of all being set at 0.

Whenever someone plans on adjusting the CO, I post, scratch the #'s on the WALL so they don't get lost as no two bikes will have the exact same #'s.
I'm guessing Yamaha, at the factory, checks CO emissions and adjusts accordingly.
 
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trepetti

It's all good!
Elite Member
Site Supporter
for what its worth, my 05 bas co of 15 on 1 and 6 on 2. i left them and do all mf fueling changes on my PCFC. its largly guess work and butt dyno testing. i am contemplating purchasing stuff from innovate. putting in an o2 sensor and setting ny afr 2ith their data logger.

Sent from my SM-G930V using Tapatalk
 

Ital

Member
Here is my idle after adjusting it with my co at +14
I've adjusted as soon as i got home from work so the bike was nice and hot
https://youtu.be/NpQ-vBv98pE

That is the RPM it runs best, if I go higher it jumps around a bit and then stabilizes again around 1300 rpm

Let me know what you guys think if that is good. Thanks!
 

FinalImpact

2 Da Street, Knobs R Gone
Super Moderator
Site Supporter
08 mine was 0/0. Ran it as high as 35/35 and at that there was no idle control recovery. Simply too much fuel.

FWIW there is no logical reason to fuel 1 - 4 differently than 2 - 3. Its neither an FJR or an R6. It has batch fueling and ignition. You can't fuel them differently and have a proper running engine.
A couple years back I connected an oscilloscope to the batch injectors and ran one side -35 the other -35. There was no change in duty cycle at low rpms.
That's because c1 changes fueling higher up the rpm band.
 

Ital

Member
08 mine was 0/0. Ran it as high as 35/35 and at that there was no idle control recovery. Simply too much fuel.

FWIW there is no logical reason to fuel 1 - 4 differently than 2 - 3. Its neither an FJR or an R6. It has batch fueling and ignition. You can't fuel them differently and have a proper running engine.
A couple years back I connected an oscilloscope to the batch injectors and ran one side -35 the other -35. There was no change in duty cycle at low rpms.
That's because c1 changes fueling higher up the rpm band.
From what I read, i found in multiple threads every time the 2008 had both settings set at zero. Finalimpact, what do you have your co set to now and what exhaust and air filter do you have? Thanks!
 

TownsendsFJR1300

2007 FZ6
Site Supporter
Here is my idle after adjusting it with my co at +14
I've adjusted as soon as i got home from work so the bike was nice and hot
https://youtu.be/NpQ-vBv98pE

That is the RPM it runs best, if I go higher it jumps around a bit and then stabilizes again around 1300 rpm

Let me know what you guys think if that is good. Thanks!
That video sounds and looks good to me...


FI, I have to disagree about the #'s. I don't believe Yamaha would haphazardly put in different CO adjustments just because...

In my old FJR, it had an issue (turned out to be a corroded wiring connection which the techs couldn't find), however I did bitch about it being so lean on the bottom end (noticeable surging below 3,000). They offered to make an "adjustment" (no further info) and I declined. They F'ed up my throttle sync (FJR) I later found (after buying a manometer for the FZ back in '09) .

And no, the FZ is not an R6 or FJR however the CO #'s adjust the same thing.

*Lastly, why would Yamaha allow those adjustments, or even make them available if not for a reason?
 
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FinalImpact

2 Da Street, Knobs R Gone
Super Moderator
Site Supporter
Ital, 0/0. See sig it has fuel controller that adjusts down low. AFR at idle is 12.5:1.

The R6 of this era had 4 Cx adjustments. All 4 went up the RPM range overlaping each other. There was NO group fire or group injection. They could have controlled each cyl independently but you don't do that as the engine would self destruct.


The FZ is the same way. C0 for idle to 2200 rpm or so and C1 from 2k to 4500. Hence driving them up lessons throttle chop. So ya. We have to agree to disagree there. All this BS about running cylinders 2/3 richer is nonsense because its hotter in the middle... NO!!! If those Cx numbers did that you would never be able to synchronize the TBs if 1 and 4 are fueled differently (different injector duty cycle) than 2/3. Not to mention the engine would run like crap and wear itself out.

Think about it. If fueling at idle is 13 parts air to 1 part fuel and turning tiny air bleed sync screw changes anything at all what happens if change that ONE part fuel? (13:1 ratio) you would never be able to compensate. Right?

Obviously turning those silly little brass sync screws to change the AIR volume could never make up the disparity if C0/C1 altered the fueling at idle of 1/4 vs 2/3. It makes zero sense. Turn up C1 to 30 and see what happens to your S2 idle.... nothing. C1 impacts fueling at a higher rpm. Not cylinder 2 and 3.

If its not raining this weekend I'll try to get the beast out and show you.
 

Ital

Member
Ital, 0/0. See sig it has fuel controller that adjusts down low. AFR at idle is 12.5:1.

The R6 of this era had 4 Cx adjustments. All 4 went up the RPM range overlaping each other. There was NO group fire or group injection. They could have controlled each cyl independently but you don't do that as the engine would self destruct.


The FZ is the same way. C0 for idle to 2200 rpm or so and C1 from 2k to 4500. Hence driving them up lessons throttle chop. So ya. We have to agree to disagree there. All this BS about running cylinders 2/3 richer is nonsense because its hotter in the middle... NO!!! If those Cx numbers did that you would never be able to synchronize the TBs if 1 and 4 are fueled differently (different injector duty cycle) than 2/3. Not to mention the engine would run like crap and wear itself out.

Think about it. If fueling at idle is 13 parts air to 1 part fuel and turning tiny air bleed sync screw changes anything at all what happens if change that ONE part fuel? (13:1 ratio) you would never be able to compensate. Right?

Obviously turning those silly little brass sync screws to change the AIR volume could never make up the disparity if C0/C1 altered the fueling at idle of 1/4 vs 2/3. It makes zero sense. Turn up C1 to 30 and see what happens to your S2 idle.... nothing. C1 impacts fueling at a higher rpm. Not cylinder 2 and 3.

If its not raining this weekend I'll try to get the beast out and show you.
ahh that makes sense, I feel I can run it a bit leaner down low and richer on top.
I think I will turn down C0 and turn up C1, I will experiment a bit... thanks!
 

FinalImpact

2 Da Street, Knobs R Gone
Super Moderator
Site Supporter
Shoot for c0 = 7, c1 = 25.
You should be able to get a nice idle, retain full idle adjustment/sync screw compensation. But was this thread the one with stinky idle as main complaint?
Maybe 0/25 to reduce throttle chop...

If so it depends what is important to you. Lean idle can lead to stalling especially with a cold engine.

O/T extreme fueling:
Here's one for you. One time I let the data logger inputs make the correction fuel map / compensation to obtain a fuel ratio of 12.8:1 from 3k up.
Well it hosed up and made it like 10:1 and although it never fouled plugs, mpgs went from 45 to 25mpg and there were few happy spots as it was so rich, it pretty much killed its performance. Reset and make manual corrections. Under high loads like idle to 4k 12.8:1 is the sweet spot with 13.1:1 taking care of business up top from ---> 4k to 13.6k where ignition cut occurs.

Few people run the Bazzaz F/C or I'd share the map. Its pretty well dialed in right now.
 
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