CO Adjustments

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DL,

While you are under the hood,

check out your Coil Tangs as seen here to see if they are not bent to a shorting position:

https://www.fjrforum....ndpost&p=714281

Also, while I was looking for electrical/intermittent gremlins, I went through all the Wires (and Spark Plug Wires) and cut Rubber Hoses as Insulators at All Areas where the Wires were Touching Metal areas. This is when I ended up Finding the Main Harness Connector and found the contamination in the Contacts...

Good Luck with this...

 
i arrived home this week to find my PCIII waiting for me. I'm going on a weekend-long trip in a few hours, so I will have to wait until monday AM to start fooling around with it. I will be sure to post what I find.

Joe

 
I'm glad I found this thread because my FJR has been driving me nuts. Its a 2005 I bought used a year and a half ago. Unfortunately a lot of my riding is in city traffic where I experience the 1500-2000rpm sluggishness/burbling a lot. I hear exhaust popping at idle and up to 5000rpm. Its really bad just under 2000rpm, which is also where the surging/hesitation/rpm hunting is the worst, but I can hear slight popping at all rpm's if the engine isn't under load and the throttle input is constant. Is the popping I hear normal lean stuff and coincident with the surging others have commented on? One dealer said "these big I-4s don't like low rpms" and the other said "they all do that". I did the Barbarian/CO mod to no effect, cleaned wiring harness that can cause problems, TBS, etc., but to no avail. Am I just experiencing the normal GenI FJR behavior, and if so does a PCIII take care of most of it? I would gladly pay $300 for a PCIII (or a lot more, dammit!) if it fixed a bike that's otherwise the exact bike I was meant to be with! Basically I just want to know if what I'm experiencing is common and can be fixed.
dlfunk,

It depends on what you mean by your use of the word "popping".

Do these engines all idle a bit roughly, either warm or cold? Yes they do. They all have what sounds like an intermittent "miss" when they are idling. I have never heard an FJR that idles completely 100% smoothly. Here's a link to

of the uneven idle sound of a healthy FJR. this one is a second gen, but they all sound pretty much like this.
[edited to add] If someone thinks they have a bike that idles significantly smoother than the one in the above video, please post up a video. I'd sure love to see it.

Do all stock 1st gens have the lean surging condition at low load / low throttle openings? IMO, yes they do. It feels like the bike is slightly speeding up and slowing down, in a randomly occurring pattern when the bike is held at a steady throttle opening. It feels similar to the way the bike feels when you are riding through gusty / turbulent air, but happening even when the air is completely still.

Over the years, and on different bikes, I have found that not everyone is sensitive to this condition, which is why some people think they don't have it when they do. It is just a sensation, and not really bad enough to cause any driveability issues. Some folks just live with it. This condition can be fully ameliorated with a PCIII. BTDT.

Do all stock FJRs have an abrupt throttle transition from trailing throttle (throttle fully closed, engine braking) to when the throttle is first cracked open? IMO, yes they do. It's because the ECU cuts all fuel to the engine under trailing throttle, so when you first crack the throttle open the power comes on abruptly. The PCIII can also help soften this transition with appropriate fuel mapping in the low and zero throttle areas.

Do all FJRs have actual backfires (popping sounds) from their stock exhausts at idle and during cruise? Not in my experience. If you have this happening you should investigate further.

Hope that helps

 
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I have a 2009 and I had the stumbling symtoms exactly as Fred described. No need to do the Barbarian mod over here, we have direct access to the ECU. Changed all my CO settings to +15 (they were all 0) and it transformed the bike. Now it will roll along happily at less than 30 MPH in 5th gear and will pick up without hesitation from there. YMMV

Don
Don I had my co set at +9 above my stock settings and it was better than stock but still I wanted it better. So I tried your +15 and went for a nice long ride today. Wow it is even better now than before. I'm pretty happy with it now. I may try +18 to see if the leaness and on/off throttle would be gone completely

Eric

 
I have a 2007. ... I've always had a snatchy problem. For instance, when going through corners, I will down shift, and when I get back on the throttle, there is a sudden jerk. blah blah blah

Thanks, Lucas
Zactly. I also did the throttle spring unwind, then the G2, then the barbarian mod ... finally the PCIII and that helped the most (this on a 2007). Still not Honda-Smooth but much better.

 
I've just started monkeying with the PCIII and the gas bench. I wanted to give an update. This is NOT the final version, but here's what I've got so far.

map1.jpg


I've got quite a bit of test time in. My single goal it to get the engine to accelerate smoothly between 1000 RPMs and 3000 RPMs. Before messing with the PCIII the engine hesitated badly if accelerating slowly from a stop. It did the same thing at 1500-2500 RPMs at light loads. I have no interest in disconnecting my O2 sensor or screwing up my fuel mileage.

The map above has come REALLY close to solving my problem. The exception is that if I accelerate rapidly from low RPMs it will still misfire, then accelerate. I am going to try to solve this by overcompensating the fuel numbers over 10% under 2500 RPMs. We'll see how that works. It would be cool to get the mapping completely straightened out, but I'm not sure it's going to happen. What it really needs at this poin is better accleration enrichment from the Throttle Position Sensor, but that's programming that we just don't have access to.

In the mean time, I will enjoy my smooth/easy acceleration. Once I get a map that I'm happy with I will be sure to share it. It will be interesting to see how well it works on another bike.

Joe

 
Joe,

For your roll-on hesitation problem, you might want to considering enabling and programming the accelerator pump option on the PCIII. It's downloadable from their web site.

Unfortunately, to get rid of the lean surging issue that plagues (mostly) first gen bikes requires the disabling of the O2 sensor. I would have to assume that any mapping / programming that you come up with will probably be considerably different than for anyone that has the O2 disconnected. Having the O2 disabled has not resulted in any appreciable loss in fuel mileage for me. YMMV (literally).

Does subtracting the fuel in the idle cells actually have an effect on the exhaust gas when the O2 is enabled? I would expect that, once the O2 gets up to temp, when the ECU goes closed loop at idle it would over-ride any fuel added or subtracted by the PCII. No?

But something else is very weird. Your map looks a whole lot different than any other PCIII map that I have ever seen for an FJR. In the area that you are adding the most fuel (1500-2000 rpm, 10-40% throttle) most maps, including those made on a dyno, are subtracting fuel. :blink:

 
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I've just started monkeying with the PCIII and the gas bench. I wanted to give an update. This is NOT the final version, but here's what I've got so far.

map1.jpg


I've got quite a bit of test time in. My single goal it to get the engine to accelerate smoothly between 1000 RPMs and 3000 RPMs. Before messing with the PCIII the engine hesitated badly if accelerating slowly from a stop. It did the same thing at 1500-2500 RPMs at light loads. I have no interest in disconnecting my O2 sensor or screwing up my fuel mileage.

The map above has come REALLY close to solving my problem. The exception is that if I accelerate rapidly from low RPMs it will still misfire, then accelerate. I am going to try to solve this by overcompensating the fuel numbers over 10% under 2500 RPMs. We'll see how that works. It would be cool to get the mapping completely straightened out, but I'm not sure it's going to happen. What it really needs at this poin is better accleration enrichment from the Throttle Position Sensor, but that's programming that we just don't have access to.

In the mean time, I will enjoy my smooth/easy acceleration. Once I get a map that I'm happy with I will be sure to share it. It will be interesting to see how well it works on another bike.

Joe
Look forward to your progress with great interest. I have a 10 and have no complaints to speak of. The map I am running is the PCV map for a Two Brothers exhaust, just one of their pre canned ones.

You ability to run the PC and the O2 sensor is intriguing to me with $4.00 gas and rising.

Look forward to more information and a map from your testing.

Thanks for investing your time and sharing it with us.

 
Hey Joe, couple of questions. First, are you going to try to do anything with the lopey idle when TP is at 0? Or can anything be done? And second, can anything be done about the on/off herky jerky throttle? I'm guessing the PCIII won't allow tuning for this?

Lucas

 
Hey Joe, couple of questions. First, are you going to try to do anything with the lopey idle when TP is at 0? Or can anything be done? And second, can anything be done about the on/off herky jerky throttle? I'm guessing the PCIII won't allow tuning for this?

Lucas
Hi Lucas,

I had to take some fuel away in irder to get my idle settled down. A setting of -10 on my PC got my CO numbers in order, and smoothed out the idle nicely. I'm happy with it.

The transition between Decel Fuel Cutout, and Acceleration Enrichment is pretty abrupt on our bikes. I don't think it can be tuned out with a PC. I will give it a look once I get my low RPM problem where I want it, but I'm not hopeful anything can be done. A lot of smart guys have already had a whack at it before me.

Joe

 
I need to put a few more miles on the bike to confirm this is the final setting, but this feels pretty good. I'm sure I will end up tinkering with it in the future, but it's pretty darn close to what I was after. Under normal operating conditions, the hesitation is all but gone. The mixture is as close as it's going to get, so any other improvement are going to have to come from the timing advance MAP, and we don't have any access to that.

Note the large enrichment numbers between 1500-2000 RPMs/2-40% TPS. The mixture is not really that lean there. I'm trying to make up for poor acceleration enrichment by the PCM. It works, but you can't tune it for every RPM/Load MAP(Just RPM/TPS), so I took a shot at the middle of the range. If I accelerate too easy or hard through this range it will still hesitate a bit. If I accelerate normally, no miss or hesitation at all.

map2.jpg


Anyone with a GenII want to give it a try? I'd like to see what someone else with the same complaint thinks of it so far.

Joe

 
Joe,

For your roll-on hesitation problem, you might want to considering enabling and programming the accelerator pump option on the PCIII. It's downloadable from their web site.
How did I miss this part of you post!?!?

Scratch that last post (I don't want to edit it thought...)

Back to the drawing board.

Joe

 
For your roll-on hesitation problem, you might want to considering enabling and programming the accelerator pump option on the PCIII. It's downloadable from their web site.

I gave that accelerator pump program a try. I loaded it on my FJR and a buddies V-Strom. We were tuning both bikes all afternoon. I ended up uninstalling it on the V-Strom. It was way too sensitive, and the slightest throttle movement added fuel. You couldn't hold the throttle still enough to make it stop. I tried turning the sensitivity down, but at 20% it still did it. Uninstalling the software cleared the problem right up. I'm not impressed with it on my bike yet.

Unfortunately, to get rid of the lean surging issue that plagues (mostly) first gen bikes requires the disabling of the O2 sensor. I would have to assume that any mapping / programming that you come up with will probably be considerably different than for anyone that has the O2 disconnected. Having the O2 disabled has not resulted in any appreciable loss in fuel mileage for me. YMMV (literally).

Does subtracting the fuel in the idle cells actually have an effect on the exhaust gas when the O2 is enabled? I would expect that, once the O2 gets up to temp, when the ECU goes closed loop at idle it would over-ride any fuel added or subtracted by the PCII. No?

If our bikes ran at closed loop all the time you'd be exactly right, but I don't believe they do. The only time I've seen any O2 activity is at steady cruise above 3000RPMs. If our bikes operated in closed loop all the time I don't think we'd see such a wide range of fuel mixtures. I wish we had visibility on the fuel trims on our bikes. It would sure help me out right now.

But something else is very weird. Your map looks a whole lot different than any other PCIII map that I have ever seen for an FJR. In the area that you are adding the most fuel (1500-2000 rpm, 10-40% throttle) most maps, including those made on a dyno, are subtracting fuel. :blink:

I can't speak for how anyone else got their numbers, but I do trust a 5 gas to tell me what's going on. It's kind of like the Automovie Urine Test. They don't lie. :) My bike was pretty lean off idle, and below 2000 RPMs. When I corrected that, a lot of my hesitation cleared up, so I am confident I'm headed in the right direction. There is also a chance that something is wrong with my bike, making it different from the others. I won't know about that until I get my hands on a few more FJrs.

 

Joe

 
Sorry the accelerator pump was of no use. I should have forewarned you that I have no experience using it.

It just seemed like it would have been a good idea for your issue.

If our bikes ran at closed loop all the time you'd be exactly right, but I don't believe they do. The only time I've seen any O2 activity is at steady cruise above 3000RPMs. If our bikes operated in closed loop all the time I don't think we'd see such a wide range of fuel mixtures. I wish we had visibility on the fuel trims on our bikes. It would sure help me out right now.
Not sure at what rpm (or if there is even an rpm range) that the closed loop mode begins. All I do know is that when I hooked up my O2 sensor concurrently with the PCIII, it starts surging on cruise again noticeably. This leads me to believe that at those times (when it is surging) the ECU is in closed loop mode, and is over-riding the fuel adjustments made by the PCIII.

I believe that the 1st gens tend to surge a bit more than the second gens. The surging that I get on my bike (with the O2 sensor connect and without the PCIII) starts as low as 2000 rpm and runs right on up past 4k rpm. It occurs whenever the throttle is held steady. It is felt more in lower gears (3rd & 4th), but I believe that the higher gear ratio of 5th is just masking the same amount of surging at the engine. If all I needed to do was spin the engine up higher(as is often suggested by people that can't feel the surging) I'd have no problem. I do not lug my engine when riding, tending to cruise at between 3500 - 4500 rpm.

I can't speak for how anyone else got their numbers, but I do trust a 5 gas to tell me what's going on. It's kind of like the Automovie Urine Test. They don't lie. :) My bike was pretty lean off idle, and below 2000 RPMs. When I corrected that, a lot of my hesitation cleared up, so I am confident I'm headed in the right direction. There is also a chance that something is wrong with my bike, making it different from the others. I won't know about that until I get my hands on a few more FJrs.
My point exactly. I don't hear of a lot of other 2nd genners complaining about hesitation in the rpm range yours has it. I wonder if yours is "unique".

 
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Sorry the accelerator pump was of no use. I should have forewarned you that I have no experience using it.

It just seemed like it would have been a good idea for your issue.

No problem. It looked pretty interesting. I was excited about it, but I sure can't make it work correctly. I haven't given up on it yet. It definitely makes significant fueling changes, and has a lot of adjustability...some of which I don't fully understand yet (like the RPM Range tool).

Not sure at what rpm (or if there is even an rpm range) that the closed loop mode begins. All I do know is that when I hooked up my O2 sensor concurrently with the PCIII, it starts surging on cruise again noticeably. This leads me to believe that at those times (when it is surging) the ECU is in closed loop mode, and is over-riding the fuel adjustments made by the PCIII.

You are a keen observer! but I haven't made any ocrrections to the fueling in any other are except 1-3k RPMs, so cruise should be unaffected.

I believe that the 1st gens tend to surge a bit more than the second gens. The surging that I get on my bike (with the O2 sensor connect and without the PCIII) starts as low as 2000 rpm and runs right on up past 4k rpm. It occurs whenever the throttle is held steady. It is felt more in lower gears (3rd & 4th), but I believe that the higher gear ratio of 5th is just masking the same amount of surging at the engine. If all I needed to do was spin the engine up higher(as is often suggested by people that can't feel the surging) I'd have no problem. I do not lug my engine when riding, tending to cruise at between 3500 - 4500 rpm.

My surge is gone with my current mapping. The hesitation, however, is elusive. I can move it around, but I haven't been able to get rid of it yet.

My point exactly. I don't hear of a lot of other 2nd genners complaining about hesitation in the rpm range yours has it. I wonder if yours is "unique".

I don't care if it is. If it's broken, I will fix it. That's what mechanics do. :)

I'm going to have to try to make it to a Tech Day, or some other place I can find a bunch of FJRs and do some testing. Good thing my 5-Gas is portable...

PS: Thanks for the feedback Fred. One of the reasons for posting this stuff, beyond sharing, is to benefit from the observations of other people.

 
dlfunk,

It depends on what you mean by your use of the word "popping".

Do all stock 1st gens have the lean surging condition at low load / low throttle openings? IMO, yes they do. It feels like the bike is slightly speeding up and slowing down, in a randomly occurring pattern when the bike is held at a steady throttle opening. It feels similar to the way the bike feels when you are riding through gusty / turbulent air, but happening even when the air is completely still.

Do all stock FJRs have an abrupt throttle transition from trailing throttle (throttle fully closed, engine braking) to when the throttle is first cracked open? IMO, yes they do. It's because the ECU cuts all fuel to the engine under trailing throttle, so when you first crack the throttle open the power comes on abruptly. The PCIII can also help soften this transition with appropriate fuel mapping in the low and zero throttle areas.

Do all FJRs have actual backfires (popping sounds) from their stock exhausts at idle and during cruise? Not in my experience. If you have this happening you should investigate further.

Hope that helps
Thank you for the response! I've experienced the throttle on/off abruptness and the slight surging of the bike at low steady rpms and even though they are annoying I guess I'm used to them and don't notice them very much. I also mentioned a slight exhaust popping/missing I can hear from idle on up to 5k. Its not a backfire, its just a not-clean sound at idle or steady throttle (even when I'm riding). It clears up if the engine is under load. Its really not that big a deal. The main thing that bothers me is what I can best describe as a gurgling/sputtering just under 2000rpm. If the bike is in neutral and I crack the throttle to just under 2000rpm it sounds a lot rougher than other rpms. It clears up a lot (but not completely) over 2000rpms. Sometimes (especially in stop-and-go traffic) this can translate into rough gear shift transitions. For example, if I'm not trying to gun it and I shift from 1st to 2nd and the engine speed ends up around 1800-2000rpm when I let out the clutch then there's like a half second where it seems like the transmission doesn't engage. If I'm accelerating and shifting a little aggressively I don't notice it, but I can't do that when I'm in traffic. This is also the rpm range where the physical surging is the worst. Otherwise the bike accelerates smoothly and there aren't any other problems. Sorry about the slightly off topic post.

dl

 
I have found what seems to be jetting nirvana for my bike. I decided to return to the accelerator pump tool after abandoning it earlier when I struggled with it. On my earlier jetting attempts I was adding enrichment during 1-3K RPMs using the higher TPS% readings. After thinking about it this week I decided to start over.

I got home tonight and started my gas measurements again. After I re-established my baseline I turned the AP Function on, with all the settings turned low, and started road testing.

Here is a quick overview of how my adjustments progressed.

On the AP Tool I started with the enrichment at 10%. Sensitivty at 50%. Number of Revolutions at 1, because I only wanted enrichment as Throttle % was increasing.

Like I discovered eariler the AP tool could cause a rapid surge at cruise, and I turned the sensitivty down until it went away. The mgaic number was 30%. I ended up at 25%, just to add a safe margin.

Next I increased the fueling in 5% increments until the hesitation started cleaing up. 30% worked well to clear up the hesitation for normal acceleration in 1st gear. At 40% it worked well for everything from light to heavy acceleration through my target RPM range without negatively affecting anything else.

If I did a low RPM rollout in a higher gear it would still hesitate. Incresing enrichment didn't seem to help at all, but increasing the number of engine revolutions worked wonders.

I ended up at the settings below. I rode it for 20 minutes of stop/go city driving and it didn't goof up a single time. I'm going to ride a few hundred miles this weekend, so we will see how these settings hold up to regular riding.

Please keep in mind that this was not nearly as easy as the summary makes it sound. This process took a couple of hours to complete. I'm not complaining...just admitting that this wasn't a cake walk by any means.

nirvana.jpg


N2.jpg


 
Make sure you log your mileage from this weekend as well. I'm curious to see what this will do to the mpg's. In theory, you're adding fuel, so the mpg's should go down a bit, right? Also, did the accelerator pump do anything for the herky jerky off/on throttle problem?

Thanks, Lucas

 
...The mgaic number was 30%. I ended up at 25%, just to add a safe margin. Next I increased the fueling in 5% increments until the hesitation started cleaing up. 30% worked well to clear up the hesitation for normal acceleration in 1st gear. At 40% it worked well for everything from light to heavy acceleration through my target RPM range without negatively affecting anything else...
I have had good luck with:

85% sensitivity

18% fuel increase

25 engine revolutions

I agree that engine revolutions makes a significant difference.

 
Make sure you log your mileage from this weekend as well. I'm curious to see what this will do to the mpg's. In theory, you're adding fuel, so the mpg's should go down a bit, right? Also, did the accelerator pump do anything for the herky jerky off/on throttle problem?

Thanks, Lucas
I'm only adding fuel during low RPM acceleration, so I don't expect it to change much. I got my first 200 miles in today. Got 38 on this fillup, but one tank is hardly proof of anything.

The only problem I have right now is if I accelerate moderately fast from under 2000 RPMs. It will still hesitate. I'm going to fool around a little bit more with it, but if I can't work this out it won't kill me. I shouldn't be accerating hard from those RPMs anyway.

I don't think it's going to be possible to change the decel/accel jump. The FI system on our bikes just doesn't make a very smooth transition on that. Since the PCIII makes modifications to existing injector pulses, I don't know how we could use one to make any changes there. You just can't modify injector pulses when there aren't any being produced.

Ion, I'll try cranking up the sensitivity and turning down the fueling. It's free to try!!

Thanks,

Joe

 
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