Power Commander III

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Blue Crab

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Just ordered a Power Commander III for my '07 FJR. Mostly trying to eliminate deceleration popping and to smooth out the idle.

What can I expect after installing this mod?

Sorry if this has been discussed before, I searched the forum but didn't see any reviews of the PC3.

 
Just ordered a Power Commander II... Mostly trying to eliminate deceleration popping and to smooth out the idle...I searched the forum but didn't see any reviews of the PC3.
Deceleration popping should only happen when your motorcycle is cold as determined by the thermostat not being open yet. During this time the Air Injection System is active. Upon deceleration the AIS injects air into the exhaust ports in the cylinder head to provide a secondary burn of left over hydrocarbons. Once the engine is warmed up (the thermostat opens) the AIS is only active at idle. If this is the popping you are talking about, the PC III won't fix it, but a set of WinPro block-off plates will.

The PC III won't have little to no impact on smooth idle. Some PC III fuel maps don't address operation until the engine is above idle. IMO, you idle not being stable can be part of or all of many things like TBS, plugs, idle speed and CO settings.

In this Forum there is a ton of info on the PC3; PC III; PCIII and other variants of the name. This Forum will not search on terms 3 letters or less. It would find Dynojet but most people don't use that in their posts. The work-around is to go to Google and type in PC III [space] site:fjrforum.com You can do any search like this regardless of the number of letters. PCIII site:fjrforum.com don't forget the .com

 

It will make your throttle control and regulation easier, take away lean surging at steady speeds, soften Yamaha's abrupt acceleration/deceleration FI mapping for better control entering corners and *may* make it run just a tad cooler.

 

 
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Didn't make any difference on my '04, but I have ridden an 06 - same as 07 - and the throttle response was not as good as my 04 and the on/off throttle transition was pretty harsh. Good luck hope it helps.

 
a set of WinPro block-off plates will.
Thanks, I'll look into a set of the block-off plates. I'm not too keen on the decel popping.

The PC III won't have little to no impact on smooth idle. Some PC III fuel maps don't address operation until the engine is above idle. IMO, you idle not being stable can be part of or all of many things like TBS, plugs, idle speed and CO settings.
I just performed a TBS on my bike, it's perfect. Also just installed a new set of Iridium plugs. Idle speed is spot on at 1,100 RPM. Not sure what else to check, but the idle is not "perfect" ... it fluctuates every now and then. I was hoping the "smoothness" map running on the PC3 would resolve this, but it sounds like it won't from what you say.

It will make your throttle control and regulation easier, take away lean surging at steady speeds, soften Yamaha's abrupt acceleration/deceleration FI mapping for better control entering corners and *may* make it run just a tad cooler.
Everything that you just mentioned are things that I've noticed about my bike. I can't wait to give the PC3 a try to see if those issues are resolved. Not sure what to do about the idle though.

 
...I just performed a TBS on my bike, it's perfect. Also just installed a new set of Iridium plugs. Idle speed is spot on at 1,100 RPM. Not sure what else to check, but the idle is not "perfect" ... it fluctuates every now and then...Not sure what to do about the idle though.
From your description it sounds like your idle fluctuation is normal. I would say to just ignore it, but some people just can't :) If your idle speed just fluctuates a little bit, every now and then, what's the harm? Other than it irritating you. Small, high performance engines with low flywheel weight may not have the same stable idle as a large displacement engine with a large flywheel and a mild state of tune.

 
All very good advice, but one more thing; if you have a shop with a dyno nearby and have the funds, get a custom map done on your bike. Running someone else's map will only get you close, no two bikes are exactly the same due to mfg tolerances.

 
From your description it sounds like your idle fluctuation is normal. I would say to just ignore it, but some people just can't :) If your idle speed just fluctuates a little bit, every now and then, what's the harm? Other than it irritating you. Small, high performance engines with low flywheel weight may not have the same stable idle as a large displacement engine with a large flywheel and a mild state of tune.
I guess I'm one of those people who just can't ignore it! :)

My new Power Commander III shipped yesterday so I should have it in a couple of days. I'll report back with my observations.

 
I installed my new PCIII and removed the PAIR (Wynpro block-off plates). Also unwound my throttle spring by one turn.

The first thing that I noticed is that the bike idles PERFECTLY now. I have no idea why... the PCIII should not have affected the idle. And the PAIR removal shouldn't affect idle either, but in any case, my idle is much smoother than before with little or none of the fluctuation that was present before... it's very steady. And the idle sounds deeper too. My wife even noticed the difference. Maybe the sound difference is due to the PAIR removal.

Riding the bike is noticeably better. I find it easier to shift now and the throttle seems to be less jerky. In the past, when making a sharp low-speed turn (in first gear), it was very difficult to give the bike a little throttle without it being jerky... like suddenly too much throttle. I think the PCIII is what fixed that (running the GenII "smoothness" map).

I really like the feel of the throttle with the spring unwound by one turn. Less stress on the wrist for sure.

My next farkle is being shipped as we speak... a G2 throttle tube. I'm pretty confident that this will be the crowning glory for the bike that will make low speed throttle maneuvers as close to perfect as possible.

Steve

 
Have an 07AE and have not had any uneven idle issues. Did the G2 and unwound the spring. Found it much better. Still haven't found a reason to do a TBS or anything else since it's so good now. When i get to the valves i'll synch em up and see if it gets better.

Let me know if you want to get rid of the block off plates.

 
I have an 07AE and my idle is always rock steady. Sometimes it's rock steady at 1000 RPM, then at the next light it will be rock steady at 750 RPM, at the 3rd light it will be rock steady at 900 RPM, and so on. I never know in advance what RPM it will idle at when I roll to a stop, but so far I have always been able to count on it being steady at whatever RPM it settles at.

The service manager at my local dealer asked, when I had it in for the spider recall and leaking fork seals recently, "Does it always do that?" Yep, it always does that. (Meaning MY bike always does that. I don't think other people's bikes do that.)

 
Have an 07AE and have not had any uneven idle issues. Did the G2 and unwound the spring. Found it much better. Still haven't found a reason to do a TBS or anything else since it's so good now. When i get to the valves i'll synch em up and see if it gets better.

Let me know if you want to get rid of the block off plates.
I've got a G2 throttle tube on order... should be here in a few days. I honestly believe that the new tube will fix the last remaining annoyance of the bike and make it perfect for me (I hate the low-speed throttle jerkiness). Regarding the block off plates, don't think I'll be getting rid of them anytime soon... I love how clean the engine looks without the PAIR system installed.

 
Put a PCIII on my 08' FJR about a month ago and have just over 1000 miles logged. I used the map for aftermarket exhaust since I am using Staintune exhausts. The PCIII reduced the popping but did not eliminate it completely. What it did do is smooth out the throttle control when rolling off the line and at slow speeds. Plus, my mileage has increased by 6 to 8 mpg. I'm quite happy with the improvements so far. What additional improvements might I see if I went to a shop and did the dyno tuning? Any idea how much I might expect to spend for the service? Just moved up from a 04' FJR to the 08' and gotta say, I LOVE IT!

Note: The av.mpg computer on the bike seems to be overly generous giving up 4 mpg extra on the readout. Based on doing the math, miles driven divided by actual gallons purchased. Can that be re-calibrated?

 
Note: The av.mpg computer on the bike seems to be overly generous giving up 4 mpg extra on the readout. Based on doing the math, miles driven divided by actual gallons purchased. Can that be re-calibrated?
This can't be fixed. The ECU determines MPG info based on how much fuel it has attempted to inject. The PCIII intercepts and adjusts the fuel injector signals, so there's no way for the ECU to know how much fuel was actually used. I just leave my display on the air temperature setting all the time now :)

 
I just installed a PCIII yesterday. I have the PAIR system blocked, and I have 2 Bros. M2s. I loaded the 2 Bros. Vale map.

First ride today, and I'm very pleased. Almost eliminated the surging at low RPMs, which sucked in traffic. 1/2 way through the ride I was thinking about the whole process and realized I had forgotten to disconnect the O2 sensor. I've read everything there is to read but can't find some things I THINK I read in the past regarding the O2 sensor.

1. Someone recommended against disconnecting the O2 sensor and explained the benefit. Am I imagining that I read this?

2. Someone else said if you DON'T disconnect the O2 sensor it effectively disables the PCIII. This seems resonable.

Also, Warchilds install is for a Gen I if I recall. Is his description of the wire color for the O2 sensor correct?

I appreciate anyone's input on this.

 
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With the O2 sensor connected, the bike will adjust injector signals to obtain a 14.7:1 air:fuel ratio during certain conditions, such as steady cruising, idling, etc. The fact that the PCIII is also adjusting those signals doesn't matter, because the PCIII adjusts them by a fixed amount no matter what, but the bike's ECU uses feedback from the O2 sensor to decide how to adjust the injector signals. This is called "closed loop" mode because of this feedback loop.

You will only enjoy the PCIII's adjustments when the bike is not in closed loop mode (aka, "open loop" - the ECU uses various environmental sensors and lookup tables to determine how much fuel to provide, but does not directly measure the results to make further adjustments; no feedback loop). If the O2 sensor is plugged in, this will mainly be during acceleration, and probably at high RPMs.

Some people choose to leave the O2 sensor plugged in because they like the better fuel economy of the closed loop mode. If you want to experience the PCIII fully as intended, then unplug the O2 sensor. It will probably improve any little bit of hesitation/surging that you are experiencing now. Of course, doing so will likely decrease your fuel mileage a bit.

Maybe someone else can answer the question about wire colors.

 
With the O2 sensor connected, the bike will adjust injector signals to obtain a 14.7:1 air:fuel ratio during certain conditions, such as steady cruising, idling, etc. The fact that the PCIII is also adjusting those signals doesn't matter, because the PCIII adjusts them by a fixed amount no matter what, but the bike's ECU uses feedback from the O2 sensor to decide how to adjust the injector signals. This is called "closed loop" mode because of this feedback loop.

You will only enjoy the PCIII's adjustments when the bike is not in closed loop mode (aka, "open loop" - the ECU uses various environmental sensors and lookup tables to determine how much fuel to provide, but does not directly measure the results to make further adjustments; no feedback loop). If the O2 sensor is plugged in, this will mainly be during acceleration, and probably at high RPMs.

Some people choose to leave the O2 sensor plugged in because they like the better fuel economy of the closed loop mode. If you want to experience the PCIII fully as intended, then unplug the O2 sensor. It will probably improve any little bit of hesitation/surging that you are experiencing now. Of course, doing so will likely decrease your fuel mileage a bit.

Maybe someone else can answer the question about wire colors.

I found another post that pointed me to the right connector for a Gen II. I disconnected the sensor last night and will see what it's like on today's commute.

 
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