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I went ahead and pulled the STV plates out and then went for a ride thinking I would see some dramatic improvement in snappyness, torque, etc. I was underwhelmed to say the least. Virtually no difference in power, whether at part throttle or WOT. I detected a slight improvement in throttle response time, but that's it. So i went ahead and machined some smaller STV plates, and installed, and saw a slight smoothing, but not much else. My conclusion right now is that either the bike is already tuned to the max and there's no room for improvement (highly doubtful), or in such a poor state of tune that it cant take advantage of it (again, somewhat doubtful). Trying to figure out why there's so little change.

(yes, the new plates are centered, the photo makes it look offset.)



Thanks Rob. Exactly the info i was looking for. As i stated way back in the original post, i'm gonna do the undersized STV's to start because i like to tinker. great thing is i can remove, resize, whatever and then return to stock if i want.

--Joel
 

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Rob, I mean this in the most respectful way but you need to spend more time learning what the pc actually does.
This. Based on rpm and throttle position, the PC adjusts the injector pulse by a % you set. It's a 2D map. It isn't enough to determine overall fueling, it's just to tweak the ECU's fueling.
 

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Discussion Starter · #104 ·
I went ahead and pulled the STV plates out and then went for a ride thinking I would see some dramatic improvement in snappyness, torque, etc. I was underwhelmed to say the least. Virtually no difference in power, whether at part throttle or WOT. I detected a slight improvement in throttle response time, but that's it.
Do you by chance have a TRE installed? If so, your experience here would lend credence to my thinking that the STV's are the primary thing/s that are altered when going from one gear to another. Mine would not open them up in 1st gear...not even close...and as a result you could give it pretty much a full handful of throttle and just barely lift the front end...maybe. With the STV's out...about 1/4 throttle has the front tire 3' in the air....so I don't believe they were programmed to open.

Besides that, every closed throttle gearchange had a hesitation when going back to full throttle like the STV's were slower to open...again, once they were removed the power comes on instantly. This tuning might differ from year to year or CA to 49 State...I don't know.

And did you guys read the link I put up from Dobeck? You remember he's the guy who INVENTED the Power Commanders...and he says they aren't 'load sensitive'...so I'm tending to believe him. But...I asked the question because I really don't know, and trying to find that particular tidbit of information on the Web is proving to be a difficult task. Seeing as the CA version of PC's blanks out any adjustments below mid-revs, (where the SD function will be working) while the 'race' versions allow you to mess about with them....just has me wondering if the IAP sensors are coming into play when the stock ECU is making use of them. Dobeck seems to be saying no.....so I guess until someone comes up with something concrete saying otherwise I'm leading toward believing him.
 

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so I guess until someone comes up with something concrete saying otherwise I'm leading toward believing him.
rob, maybe this will help...

So if I took my power commander and set the entire map (every single box) to zero....(or just deleted the map entirely) by your thinking it won't run.

Wrong.

It will run exactly like if the power commander wasn't hooked up at all. But let's say we change one single box (let's say 10 percent throttle and 2000 rpm) to +1

Then

At every other box it will run like stock, and at that parameter (10% throttle and 2000 rpm) it will run exactly like stock...but with an extra 1% more injector duty cycle. Change the number to -1 and it will be exactly like stock minus 1% of the injector duty cycle.

The stock ECU is still doing all of the work it would normally do using all the sensors it normally would to control the injectors.

Make sense?
 

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just has me wondering if the IAP sensors are coming into play when the stock ECU is making use of them. Dobeck seems to be saying no.....so I guess until someone comes up with something concrete saying otherwise I'm leading toward believing him.
Dobeck is saying the PC doesn't use the IAP sensor, and he's right. He is not saying that the ECU is ignoring the IAP sensor, though.

The ECU uses all of the sensors to generate a SD or closed loop or whatever it would normally do map...THEN the PC tweaks it after the fact (with a basic 2 dimensional AN tweak)

Speaking of sensors...you can even leave your stock O2 sensor plugged in while running a PC. The ECU will look at the O2 sensor and modify the stock fuel tables in real time closed loop, just like it would without a PC. I used to do it with my Busa. 177hp and 44mpg!!!!
 

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Discussion Starter · #107 ·
Sorry for seeming to be so dense...I can't argue that I'm not sometimes.:) BUT....I think I just found the answer that I've been seeking: http://kawasakiworld.com/zx-12r/47321-how-fix-muzzy-flat-spot.html

Now what they're saying makes sense to me! Horray! To paraphrase it and save you from wading through 5 pages: The ZX12's with Muzzy exhaust were having a problem with a bad flat-spot off idle to about 3000 and no amount of PC tuning was solving it. People were giving up saying it couldn't be fixed...but a fellow DID fix it....by reflashing the ECU. The Kawasaki unit is very much like ours in that it runs SD at light loads then switches to A/N and this is why the PC wasn't able to tune out the bog.

The bog was happening when the ECU was running in SD mode...and wasn't making the changes shown on the map! Only when the fellow reflashed the internal SD map was the bog conquered.....so if this is all true, it fully explains why the PC isn't modding the fueling when in SD mode...because it can't!:)

The CA Compliant PCIII apparently won't allow you to muck about with the low rpm fueling at all...which is likely where the engine must run to pass CA emissions. And seeing that SD will normally only be working at 10% throttle and down, it also seems to explain why most people don't get big gas mileage improvements when commuting after PC tuning. If they run the bike harder where the changes are taking effect then they can see better or worse depending on how it's been tuned, but going for a 'Max Mileage' type tune won't really work with the PC. At least that's what I'm thinking right now. The TEKA WILL change the fueling across the board, so if someone is interested in 'Max Mileage' stuff....the TEKA is the tip.:)
 

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The bog was happening when the ECU was running in SD mode...and wasn't making the changes shown on the map! Only when the fellow reflashed the internal SD map was the bog conquered.....so if this is all true, it fully explains why the PC isn't modding the fueling when in SD mode...because it can't!:)
The guy in your link has the software and ability to edit individual aspects of the ECU maps directly. We can't do that for the SV...or at least the 650.

The TEKA WILL change the fueling across the board
Yea, JUST LIKE THE PC. Neither the PC or TEKA can edit the fuel parameters of an SD map and leave an AN map unchanged, nor can they affect whether the ECU elects to use SD vs AN mapping at any given moment. They both just add 10% fuel (or whatever number you chose to input) to everything at that throttle position and RPM, albeit by different methods.

I'm done arguing. Believe whatever you want.
 

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Discussion Starter · #109 ·
Wow...I didn't realize you were arguing. With whom? ME? Nope....no argument here. I'm just trying to wrap my head around how something works, and say it does 'this and that' without anything to back it up really doesn't help.

The stock ECU is chock full of maps, and when in SD mode those maps are constantly switching to the one that's programmed for whatever particular manifold pressure is being read at that instant. I saw (with my own eyes) the idle mixture and light throttle change with TEKA changes....and still have read nothing that says the PC can do the same. The guy who invented it says it can't. The Kawasaki guys had to reprogram the SD maps to do what the PC couldn't. I would really like to see something that explains HOW the PC can affect the SD map...beyond 'yes it does'. Not arguing with you...just asking the question and trying to find the answer. You very well might be correct...and don't have any grudge or something.:) If you should happen to find some documentation on this subject...please post it up! Knowledge is Power.
 

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I would really like to see something that explains HOW the PC can affect the SD map...beyond 'yes it does'.
Rob. It simply intercepts the signal into the fuel injector and modifies it by the % you enter, then outputs a new signal into the injector.

Who gives a crap about maps. It doesn't matter how the signal was created!!!!

IF A FUEL INJECTOR IS FIRING, THE PC CAN ADJUST IT!!!

I can't figure out how you can't understand that. I'm starting to think you're just messing with me.
 

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I'm just trying to wrap my head around how something works, and say it does 'this and that' without anything to back it up really doesn't help.
OK, let me help you by using the 2 links you posted as well as a youtube link

I saw (with my own eyes) the idle mixture and light throttle change with TEKA changes....and still have read nothing that says the PC can do the same. The guy who invented it says it can't.
https://www.youtube.com/watch?v=PuBIAav8ktA skip to 230. He's using autotune to build a map and inserting the values he gets into the PC. Notice the AFR and idle improves as he does it. I can see it with my own eyes, and judging by the post count 12,000 other people have too.


The guy who invented it says it can't.
Show me where he said that? All he said in your link was that PC is AN technology. It is YOU that is misinterpreting it to mean "the PC can only tune AN technology".

The Kawasaki guys had to reprogram the SD maps to do what the PC couldn't.
Yes, So what? That kind of advanced editing software isn't available to us SV riders.

If there are two ECU maps that overlap at a given rpm/throttle position, the PC will just add the same amount of fuel correction to both...just like your link pointed out. I've never heard of that being a problem for anybody, other than the Ninja people with exhaust mods in your link.

By the way...your TEKA does the same thing. If you really think your TEKA is special and can tell the difference between multiple maps, then post screenshots of individual SD and AN maps like the one in your link.

I would really like to see something that explains HOW the PC can affect the SD map...beyond 'yes it does'.
Are you even reading what you post??? The reprogrammer in the kawasaki thread you linked says in post #9 how a PC works. It doesn't rewrite the internal ECU code...it just intercepts the signal to the injector and modifies it...just like I have been saying.
 

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hmmm... yes i have one of steve's switchable TRE's installed. The issue i've got is that with STV's in or out, the power seems to be the same. full throttle, and the bike will barely lift the wheel as everyone else seems to indicate it should. i'll try to switch the TRE and see if it makes a difference, but what else would be limiting the power? As an indicator, it doesn't seem to be much quicker than my 99 honda VFR, even though it should have more torque and weighs less.

Do you by chance have a TRE installed? If so, your experience here would lend credence to my thinking that the STV's are the primary thing/s that are altered when going from one gear to another. Mine would not open them up in 1st gear...not even close...and as a result you could give it pretty much a full handful of throttle and just barely lift the front end...maybe. With the STV's out...about 1/4 throttle has the front tire 3' in the air....so I don't believe they were programmed to open.

Besides that, every closed throttle gearchange had a hesitation when going back to full throttle like the STV's were slower to open...again, once they were removed the power comes on instantly. This tuning might differ from year to year or CA to 49 State...I don't know.

And did you guys read the link I put up from Dobeck? You remember he's the guy who INVENTED the Power Commanders...and he says they aren't 'load sensitive'...so I'm tending to believe him. But...I asked the question because I really don't know, and trying to find that particular tidbit of information on the Web is proving to be a difficult task. Seeing as the CA version of PC's blanks out any adjustments below mid-revs, (where the SD function will be working) while the 'race' versions allow you to mess about with them....just has me wondering if the IAP sensors are coming into play when the stock ECU is making use of them. Dobeck seems to be saying no.....so I guess until someone comes up with something concrete saying otherwise I'm leading toward believing him.
 

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hmmm... yes i have one of steve's switchable TRE's installed. The issue i've got is that with STV's in or out, the power seems to be the same. full throttle, and the bike will barely lift the wheel as everyone else seems to indicate it should. i'll try to switch the TRE and see if it makes a difference, but what else would be limiting the power? As an indicator, it doesn't seem to be much quicker than my 99 honda VFR, even though it should have more torque and weighs less.
I will attest that with the STV's out of an SV1000S, it did not become a wheelie monster for me. All my power wheelies have been off raw power throttle pulls being in the right gear at the right moment. IE low 2nd gear and wacking open. It does not happen ALL the time. Wheelies are very rare for me. Perhaps I'm just too fat for the bike, 185 lbs w/o gear.

Just doing a WOT run won't show you the difference of having the STV's out. You need to hit the corners and roll on/off the throttle. The low and mid range will show you the improvement. Just straight line acceleration with STV's in or out is nearly identical. You wack it open, STV's stick open, you stay on the throttle the STV's won't shut. It's about the throttle control when you reduce it after you've had it open and then roll it back open. Hit some corners, then you'll feel it.
 

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Yep, the main thing I noticed when I got rid of the STVs is that the throttle response was significantly better (quicker). This was especially true in the lower gears. That did lead to easier wheelies, but it doesn't come up on me unless I'm trying.
 

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I have a question for everyone who has gotten rid of STVs and fast idle. Is there a good way to add a fast idle lever? Sometimes it would be nice to be able to start the bike and have it idle without nursing the throttle. I suppose I could get an idle adjustment cable off something else that I could turn by hand rather than needing a screwdriver, but a fast idle cable on the handlebars would be nice.
 

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Junkie,

by fast idle, are you referring to the ECU goes into Open Loop when the motor is cold?
 

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Discussion Starter · #117 ·
I have a question for everyone who has gotten rid of STVs and fast idle. Is there a good way to add a fast idle lever? Sometimes it would be nice to be able to start the bike and have it idle without nursing the throttle. I suppose I could get an idle adjustment cable off something else that I could turn by hand rather than needing a screwdriver, but a fast idle cable on the handlebars would be nice.
On the bars would be asking a lot...but a manual button to pull hidden inside the frame somewhere would be pretty simple to fab up. Something like this: [ame]http://www.amazon.com/Dorman-HELP-55101-Choke-Conversion/dp/B000CO7CK0/ref=sr_1_5?ie=UTF8&qid=1427252785&sr=8-5&keywords=manual+choke+cable[/ame] with the cable end attached to the Fast Idle cam lever so you could pull it forward a bit when you wanted it to idle faster. Would take a little ingenuity to do...but it could be made to work.

Getting the cable up to the bars could be done..but would be a lot harder with them moving so much...would need solidly mounted both ends so it wouldn't change revs when you steer, but shouldn't be beyond doing if you are so inclined. Mine almost never needs 'help' once it's running...how fast are you idling when hot? Setting mine to showing 1400 at most has it at 1250 most of the time and will stay running about 1200 when cold with no attention.
 

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From the factory, isn't there a servo that opens the butterflies a little when the engine is cold? There's something that significantly increases the idle rpm when cold.

When you say "open loop", what do you mean? With no O2 sensor, isn't it always open loop?

I suppose I could figure out a cable operated device to open the throttle a little bit when actuated. I know there are some EFI bikes with fast idle levers mounted on the bars (like chokes on many carb'd bikes).
 

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Discussion Starter · #119 ·
The STV's are connected directly to the Fast Idle Cam...so when they're fully open the FI is fully activated. As the engine warms up the STV's close down which drops the FI. Without the STV's in place....you'd need to leave the arm and roller on the end that the Fast Idle Cam pushes on to give you something to pull on, or activate the throttle directly at the grip through the cables. Or something.
 

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When you say "open loop", what do you mean? With no O2 sensor, isn't it always open loop?
Okay, the confusion was on my behalf. I wasn't aware the fast idle was due to the STV system. I currently only have the butterflies removed from the STV's, so my bike still fast idles on warm up to which I confused with running open loop. You are correct, with no O2 sensor closed loop isn't happening.

I have had the D'eccose circuit board in my "mod" box. Just haven't taken the time to pull the tank off and remove the rest of the system. I want to do a valve check soon so that's a good time to pull the rest of the STV junk off and do it.

I suppose I could figure out a cable operated device to open the throttle a little bit when actuated. I know there are some EFI bikes with fast idle levers mounted on the bars (like chokes on many carb'd bikes).
The 05 Ducati Monster 1000 has such a lever on the handle bars. I would imagine it could be rigged up to work on the SV?
 
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