what mods can a busa handle without a PC??
- Thread starter sproket
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Don't listen to me, when I tell you that the steel clutch plates have, "memory"... and if you install the clutch plates any old way, you'll ruin the whole assembly... i.e., clutch drag, hard shifting, difficult to find neutral, clutch slippage at high rpm, increased wear factor, etc.
Don't listen to me, when the logic shows you; There are fuel maps set to work in fail-safe mode. You don't see the analog is still feeding input voltages, so the ECM can finalize the correct spray at... partial analog/partial safe-mode.
I bought a computer bike (ZX14) in late April. It took a few weeks to watch the ECU default to backup when the tre came out for the Kawi 14.
Someone soldered a 270 ohm resistor in-line with the GPS. The same code (6 locked) came up on the dash, as if you installed a tre. That was my quick learning curve about DFI (digital fuel injection) and the black box. Meaning, the performance is inside the ECU. The analog settings are there for de-tuning purposes. You have to ride a stock 14 in "linear" acceleration, and then ride the bike when the ECU is triggered to open the subthrottle plates. It then rides like a BUSA!
But, you Professor, do not see the correlation; Observing the 270 ohm resistor triggering the 14's ECU, as does the same tre triggering, "c31" does in the Busa's ECM. Observing the de-tuned 'analog ride' as opposed to the 'fail-safe ride' the tre induced, is not proof enough?
This is so easy to understand, it's no wonder most people cannot walk themselves thru the 3 things to make an engine run. Now, add the ECM as another variable, and you will fall deeper into figuring out how to fix your bikes. I will reintroduce this (14) computer bike, because leaving out emperical knowledge validates everything I say. I can even back it up any statement using either the Busa or other bike's shop manual.
This is a study understanding and interpreting the problems associated with troubleshooting a drive-ability issue. The book is right there to prove me wrong, and here I am walking you through code 31. Tell me, who is confused here.
Professor, here is a quote by Chairman Mao Tse Tung's, Little Red Book; "No investigation, No right to speak."
Have you experimented with the ECM to quantify the results? Have you tried to set the low/high fuel maps in fail-safe mode? I have... On a 14. Did you reinstall the sensors back in analog mode to tell the seat of the pants difference? I had 4 backup codes in play... The bike was super responsive. I used no aftermarket parts. I simply disconnected sensors.
Professor, Do you still not understand what the TRE does to the ECU? Until you do, you are making, "assumptions." Read the shop manual. Tell me what page you don't understand. I have an imaginary Busa on the rack. We have a code 31. That c31 is part of the GPS sensor. How do you repair the bike? What caused the bike to set a code 31? How does the ECM resolve the situation so the bike still runs?
Don't listen to me, when the logic shows you; There are fuel maps set to work in fail-safe mode. You don't see the analog is still feeding input voltages, so the ECM can finalize the correct spray at... partial analog/partial safe-mode.
I bought a computer bike (ZX14) in late April. It took a few weeks to watch the ECU default to backup when the tre came out for the Kawi 14.
Someone soldered a 270 ohm resistor in-line with the GPS. The same code (6 locked) came up on the dash, as if you installed a tre. That was my quick learning curve about DFI (digital fuel injection) and the black box. Meaning, the performance is inside the ECU. The analog settings are there for de-tuning purposes. You have to ride a stock 14 in "linear" acceleration, and then ride the bike when the ECU is triggered to open the subthrottle plates. It then rides like a BUSA!
But, you Professor, do not see the correlation; Observing the 270 ohm resistor triggering the 14's ECU, as does the same tre triggering, "c31" does in the Busa's ECM. Observing the de-tuned 'analog ride' as opposed to the 'fail-safe ride' the tre induced, is not proof enough?
This is so easy to understand, it's no wonder most people cannot walk themselves thru the 3 things to make an engine run. Now, add the ECM as another variable, and you will fall deeper into figuring out how to fix your bikes. I will reintroduce this (14) computer bike, because leaving out emperical knowledge validates everything I say. I can even back it up any statement using either the Busa or other bike's shop manual.
This is a study understanding and interpreting the problems associated with troubleshooting a drive-ability issue. The book is right there to prove me wrong, and here I am walking you through code 31. Tell me, who is confused here.
Professor, here is a quote by Chairman Mao Tse Tung's, Little Red Book; "No investigation, No right to speak."
Have you experimented with the ECM to quantify the results? Have you tried to set the low/high fuel maps in fail-safe mode? I have... On a 14. Did you reinstall the sensors back in analog mode to tell the seat of the pants difference? I had 4 backup codes in play... The bike was super responsive. I used no aftermarket parts. I simply disconnected sensors.
Professor, Do you still not understand what the TRE does to the ECU? Until you do, you are making, "assumptions." Read the shop manual. Tell me what page you don't understand. I have an imaginary Busa on the rack. We have a code 31. That c31 is part of the GPS sensor. How do you repair the bike? What caused the bike to set a code 31? How does the ECM resolve the situation so the bike still runs?
2busa,
Performance on a stock Busa will improve with a Power Commander. The PC does not put the ECU in “default†mode. Suzuki had other worries when they tuned the Busa, Emissions, warranty etc. That is the reason there is some potential in tuning a stock Busa.
To dispute some of items you have posted in this tread.
1) “This bike is fuel injected. That means no 02 sensor in the exhaust system.“
Not all fuel infected motorcycles are without 02 sensors. It even appears some non-US spec Hayabusa’s are equipped with 02 Sensors. Maybe you meant the Busa has a open loop fuel injection system.
2) “TRE, GPS mod, S-Healer will harvest ECU codes.â€
The GPS, Speedohealer and TRE do not set the ECU in backup or trigger an ECU code. They are sending information to the ECU that is in parameters with the existing sensors they replace/supplement. Because the ECU is seeing information in spec, it responds accordingly.
3) “It's a comedy; Watching a rich running PC disrupt a perfect running bike….â€
A rich running PC is not a properly tuned PC. There is a difference. There is no doubt that some are screwed up, mine was tuned and was not optimal. It had to be changed a bit. Guess what, I picked up 1.75 MPH in the ¼ by only touching the 90-100% settings from 7000rpm up. Didn’t set any ECU trouble codes either and it was not in “backup modeâ€
4) “Have you experimented with the ECM to quantify the results?â€
Yes, I have experimented with the ECU a bit. Where do you think the measurements in the other thread came from? I didn’t pull them out of thin air or from testing on a ZX14. They came from a busa….. Yes, Virginia, these are real measurements.
5) “Don't listen to me, when I tell you that the steel clutch plates have, "memory"... and if you install the clutch plates any old way, you'll ruin the whole assembly... i.e., clutch drag, hard shifting, difficult to find neutral, clutch slippage at high rpm, increased wear factor, etc.â€
I guess you came up with this from another thread. I agree if the steel plates are not flat, it can cause drag when the clutch is pulled in. That is the reason the service manual calls for no more the .004†distortion. I disagree with the plates being able to be moved if they are in good shape.
6) “Read the shop manual. Tell me what page you don't understand. I have an imaginary Busa on the rack. “I’m not sure your imaginary Busa is like any other on this planet.
You base so much of your arguments on the ZX14 and installation of a TRE on it. The majority of the change in the 14 with a TRE installed comes from the secondary <s>injectors</s> throttle plates opening faster. The TRE locks it in 6th gear settings. How, or why on the 14, I don’t know (nor care at this time). I do know there are no secondary <s>injectors</s> throttle plates on the Busa.
Find me someone who agrees with you opinions. I’m seeing quite a few that disagree and have been hearing from a few by PM as well.
Edited to fix misleading statement on my part.
Performance on a stock Busa will improve with a Power Commander. The PC does not put the ECU in “default†mode. Suzuki had other worries when they tuned the Busa, Emissions, warranty etc. That is the reason there is some potential in tuning a stock Busa.
To dispute some of items you have posted in this tread.
1) “This bike is fuel injected. That means no 02 sensor in the exhaust system.“
Not all fuel infected motorcycles are without 02 sensors. It even appears some non-US spec Hayabusa’s are equipped with 02 Sensors. Maybe you meant the Busa has a open loop fuel injection system.
2) “TRE, GPS mod, S-Healer will harvest ECU codes.â€
The GPS, Speedohealer and TRE do not set the ECU in backup or trigger an ECU code. They are sending information to the ECU that is in parameters with the existing sensors they replace/supplement. Because the ECU is seeing information in spec, it responds accordingly.
3) “It's a comedy; Watching a rich running PC disrupt a perfect running bike….â€
A rich running PC is not a properly tuned PC. There is a difference. There is no doubt that some are screwed up, mine was tuned and was not optimal. It had to be changed a bit. Guess what, I picked up 1.75 MPH in the ¼ by only touching the 90-100% settings from 7000rpm up. Didn’t set any ECU trouble codes either and it was not in “backup modeâ€
4) “Have you experimented with the ECM to quantify the results?â€
Yes, I have experimented with the ECU a bit. Where do you think the measurements in the other thread came from? I didn’t pull them out of thin air or from testing on a ZX14. They came from a busa….. Yes, Virginia, these are real measurements.
5) “Don't listen to me, when I tell you that the steel clutch plates have, "memory"... and if you install the clutch plates any old way, you'll ruin the whole assembly... i.e., clutch drag, hard shifting, difficult to find neutral, clutch slippage at high rpm, increased wear factor, etc.â€
I guess you came up with this from another thread. I agree if the steel plates are not flat, it can cause drag when the clutch is pulled in. That is the reason the service manual calls for no more the .004†distortion. I disagree with the plates being able to be moved if they are in good shape.
6) “Read the shop manual. Tell me what page you don't understand. I have an imaginary Busa on the rack. “I’m not sure your imaginary Busa is like any other on this planet.
You base so much of your arguments on the ZX14 and installation of a TRE on it. The majority of the change in the 14 with a TRE installed comes from the secondary <s>injectors</s> throttle plates opening faster. The TRE locks it in 6th gear settings. How, or why on the 14, I don’t know (nor care at this time). I do know there are no secondary <s>injectors</s> throttle plates on the Busa.
Find me someone who agrees with you opinions. I’m seeing quite a few that disagree and have been hearing from a few by PM as well.
Edited to fix misleading statement on my part.
First of all, the PC is out of the bikes wire harness loop. Meaning, the PC adds voltage to the injector (after the map plot) signal. No code is set. Let's establish this right off. Show me where I ever mention, "a PC spits a code." I understand both the TFI/PC injector setup.
I figured you'd all understand the difference between open and closed loop. I was simply tapping you on the shoulder to remind you, we are talking about FI (OL) on the Busa. True, I've been out of the industry for 6 years, and did not keep up with any one's (other 02) product line.
The 'secondary injectors' are not 4 more fuel injectors to make 8 total. Technically (strictly book terms I use for both bikes, so there is no confusion) the 14's 'Subthrottle" plates are fully opened by a tre/270 ohm resistor. The ECU recognises an, "Output Signal Unstable Range or Criteria" voltage signal, and spits a code. The GPS defaults to, "backup" and guess what? The ECU sets a 6 lock, matching the same (not exactly of course) ECM computer as the Busa.
Notice the change by a simple wire connection with the, now strange "Unstable" unit plugged in between the correct "Output Signal." Funny how I can wire in an ohm resistor and achieve another unstable signal and boom, a dramatic improvement in the driveavility. Interesting observation. I then start removing more sensors, and more tune improves. Wire in a TFI, the bike smooths out even more, but right off, the throttle has a dead spot. I turn off the TFI and the dead spot is gone. The crisp throttle response is back. Same feeling Spro feels when he's toggling the analog stock condition, or when he re-installs the tre.... sans the PC.
This double plate action is what gives the 14 the, "Linear" feel when you ride it.. For the old farts; Like a CV (constant velocity) carb used to do at WOT... Lag. You might as well learn how both bike work. The new Busa might use similar technology if they want to edge ahead on the 14.
For #2, Professor. Are you sure? You quote. "They are sending information to the ECU that is in parameters with the existing sensors'... 'Because the ECU is seeing information in spec, it responds accordingly." Professor, Watch your words blow right into a 'fail-safe' mode..
Professor, answer me this: Pg. 4~31 (near bottom). Is the 6th gear signal fixed after you install a tre. Yes or No.
I figured you'd all understand the difference between open and closed loop. I was simply tapping you on the shoulder to remind you, we are talking about FI (OL) on the Busa. True, I've been out of the industry for 6 years, and did not keep up with any one's (other 02) product line.
The 'secondary injectors' are not 4 more fuel injectors to make 8 total. Technically (strictly book terms I use for both bikes, so there is no confusion) the 14's 'Subthrottle" plates are fully opened by a tre/270 ohm resistor. The ECU recognises an, "Output Signal Unstable Range or Criteria" voltage signal, and spits a code. The GPS defaults to, "backup" and guess what? The ECU sets a 6 lock, matching the same (not exactly of course) ECM computer as the Busa.
Notice the change by a simple wire connection with the, now strange "Unstable" unit plugged in between the correct "Output Signal." Funny how I can wire in an ohm resistor and achieve another unstable signal and boom, a dramatic improvement in the driveavility. Interesting observation. I then start removing more sensors, and more tune improves. Wire in a TFI, the bike smooths out even more, but right off, the throttle has a dead spot. I turn off the TFI and the dead spot is gone. The crisp throttle response is back. Same feeling Spro feels when he's toggling the analog stock condition, or when he re-installs the tre.... sans the PC.
This double plate action is what gives the 14 the, "Linear" feel when you ride it.. For the old farts; Like a CV (constant velocity) carb used to do at WOT... Lag. You might as well learn how both bike work. The new Busa might use similar technology if they want to edge ahead on the 14.
For #2, Professor. Are you sure? You quote. "They are sending information to the ECU that is in parameters with the existing sensors'... 'Because the ECU is seeing information in spec, it responds accordingly." Professor, Watch your words blow right into a 'fail-safe' mode..
Professor, answer me this: Pg. 4~31 (near bottom). Is the 6th gear signal fixed after you install a tre. Yes or No.
Fixed meaning the ECU is always acting like it is in 6th gear? Or fixed like something is wrong with the 6th gear signal. I think you are asking the first question. So my answer is accordingly.
NO!
The ECU responds in a constant in a constant 5th gear state after you install a simple TRE.
That is one of two main reason people install a TRE. To get past the 6th gear rev limiter. If it is “fixed†in 6th gear the engine will only rev to 10,200. In the other gears it will rev to 10,600rpm.
Thank you. Professor.
I meant if on the clock display, or somewhere on the LCD. I'm trying to understand if the clock or someplace else is acting like a "fail-safe" signal. I know the display is a flashing FI or a 6th gear in the shift window is locked on the 14. These are a few "Check ECU" warnings.
Has any one downloaded the, "Dealer Mode" code to verify c31 has been set, if not more codes set. Yes or No.
Please direct me to the (pg #?) information where in the shop manual it says, there is a 5th gear signal handling the failed GPS voltage signal.
Please direct me to the "Abstract" where it says the tre has the capability to hold a 5th gear voltage (fail-safe) signal and override code 31.
http://www.google.com/patents
Tell me the combined GPS/TRE signal is doing something different than what it says at the bottom of page 4~31.
I meant if on the clock display, or somewhere on the LCD. I'm trying to understand if the clock or someplace else is acting like a "fail-safe" signal. I know the display is a flashing FI or a 6th gear in the shift window is locked on the 14. These are a few "Check ECU" warnings.
Has any one downloaded the, "Dealer Mode" code to verify c31 has been set, if not more codes set. Yes or No.
Please direct me to the (pg #?) information where in the shop manual it says, there is a 5th gear signal handling the failed GPS voltage signal.
Please direct me to the "Abstract" where it says the tre has the capability to hold a 5th gear voltage (fail-safe) signal and override code 31.
http://www.google.com/patents
Tell me the combined GPS/TRE signal is doing something different than what it says at the bottom of page 4~31.
rdwarrior... Yes, I am running the Busa with those mods and have not had any issues with it. No stalling, fouling of plugs, running excessively rich/lean, nothing. Do I think it would benefit from tuning? Yes. Not necessarily PCIII, but yes, tuning will make the throttle transitions smoother, more predictable etc.
2busa, no offense, but you seem pretty hard pressed to get ppl to understand and/or agree with you on tuning etc, the ECM/ECU/PCM controlled bikes. If I were you, I would type a little more accurately, using the correct terminology will help your cause. Like, instead of the Busa not having an O2, then saying (OL) call it what it is, OLSD...Open Loop Speed Density. Without a MAF/MAS it is Speed Density, meaning the PCM is programmed that xx rpm @ yy baro = need for zz fuel to maintain proper AFR, and this references the MAP, RPM signal, and O2 sensors. OLSD uses only the MAP and RPM, there is no other check using the O2s.
As for the stock Busa, or any other stock public available bike, the factory has to tune, or if you feel better calling it de-tuned fine, for a compromise of regulated emissions, economy and performance, same as cars. I've tuned factory stock cars and picked up some very decent power, verified on a dyno and at the track.
Why dont you take your theories and apply them at the track, or at least a dyno and then post up the findings. How? Well, use your Busa to run on a dyno, three runs, corrected for SAE. Then put the TRE/GPS or whatever you want to do, make three runs, then again using the PCIII. Post results and we can go from there.
Respectfully,
Charlie
As for the stock Busa, or any other stock public available bike, the factory has to tune, or if you feel better calling it de-tuned fine, for a compromise of regulated emissions, economy and performance, same as cars. I've tuned factory stock cars and picked up some very decent power, verified on a dyno and at the track.
Why dont you take your theories and apply them at the track, or at least a dyno and then post up the findings. How? Well, use your Busa to run on a dyno, three runs, corrected for SAE. Then put the TRE/GPS or whatever you want to do, make three runs, then again using the PCIII. Post results and we can go from there.
Respectfully,
Charlie
CAT, Spro is scratching his head and can't keep up at it is. I'll assume even more feel the same way. CAT, you and Toona speak tech. I could read this all day. My deal is a challenge to myself. I'm wondering if I can show how a computer bike works and how to repair it. First, you need the basics. I'm more the abstract thinker being less technical, and explaining the complex into a more simple way of watching the, "action/reaction" way things happen between a sensor and computer.
We can all follow by downloading the shop manual. You can watch the diagnosis I use to repair said code. You can see if the computer received the proper "pre-set" signal to the ECM by matching the book's voltage value.
Keep it simple? I'm trying. I don't need to dyno the bike. The book, the members here, are giving me enough to see the bike does perform different. I also have felt the seat of the pants changes on my own computer bike using a deeper code set.
The joke I see, are the perpetual fallacies going on as to what the manual says the FI system does and what everyone else says it does.
CAT, your last sentence in the first paragraph says it all... "OLSD uses only the map/rpm..." says it all.
The reason I mention the tune factor, is to show the tre triggering the fail-safe... period. The fallacy that a 5th gear voltage signal is the rev limiter fix when you install the tre is incorrect... according to the shop manual.
I don't see the 5th gear info coming from the Professor. That's because there is none. Someone may have shifted gears, ohm'd the values and came up with a 5th gear signal for all I know. As far as my personal analog-to-digital settings for tuning goes, no one has ever tried it as far as I know. I have, and felt the difference connecting and reconnecting the sensors. The fallacy flying is the fear engine damage will occur. The manual says nothing about engine damage defaulting to fail-safe.
Professor, the 5th gear data please. I need to contact Suzuki and tell them to revise c31 as to what the ECM reads and does; switching to the 5th gear maps instead.
We can all follow by downloading the shop manual. You can watch the diagnosis I use to repair said code. You can see if the computer received the proper "pre-set" signal to the ECM by matching the book's voltage value.
Keep it simple? I'm trying. I don't need to dyno the bike. The book, the members here, are giving me enough to see the bike does perform different. I also have felt the seat of the pants changes on my own computer bike using a deeper code set.
The joke I see, are the perpetual fallacies going on as to what the manual says the FI system does and what everyone else says it does.
CAT, your last sentence in the first paragraph says it all... "OLSD uses only the map/rpm..." says it all.
The reason I mention the tune factor, is to show the tre triggering the fail-safe... period. The fallacy that a 5th gear voltage signal is the rev limiter fix when you install the tre is incorrect... according to the shop manual.
I don't see the 5th gear info coming from the Professor. That's because there is none. Someone may have shifted gears, ohm'd the values and came up with a 5th gear signal for all I know. As far as my personal analog-to-digital settings for tuning goes, no one has ever tried it as far as I know. I have, and felt the difference connecting and reconnecting the sensors. The fallacy flying is the fear engine damage will occur. The manual says nothing about engine damage defaulting to fail-safe.
Professor, the 5th gear data please. I need to contact Suzuki and tell them to revise c31 as to what the ECM reads and does; switching to the 5th gear maps instead.
Well, me personally, I would love to splice in an Accel DFI VII box, and run the engine functions (Injectors, Rev limiter, Advance/Retard etc) off the Accel box, and the "analog" gauges thru the almost dead factory ECM. However, $2100 for the setup is a bit much for a simple triple threat (Daily Rider, Occasional Drag and or Track Busa) Busa, not to mention all the wiring needing to be spliced, tinned, soldered, shrinkwrapped and tucked away. Too much hassle.
I personally dont under the TRE and all the Hype around it. I do know on the ZX13.5 it gets the secondary throttle blades to open early (or basically whenever the throttle is cracked) which makes the 13.5 perform dramatically better. I am using a BoostbySmith modified GPS w/ Gear Indic. which has a "TRE" built into the modded GPS, basically cross-references the ECM to think the Busa is in 5th gear when it really is in 6th. My understanding is, the factory ECM is programmed that in 6th gear the limited is two fold, one at 186mph (a product of the European GUV from 1999 that decided it was unnecessary to have ANY vehicle sold to the public capable of speeds beyond 186...bastages) and one limiter set at 10,200rpms for 6th gear only (10,600 for 1-5 gears).
Well, back to my regularly scheduled programming.
Charlie
I personally dont under the TRE and all the Hype around it. I do know on the ZX13.5 it gets the secondary throttle blades to open early (or basically whenever the throttle is cracked) which makes the 13.5 perform dramatically better. I am using a BoostbySmith modified GPS w/ Gear Indic. which has a "TRE" built into the modded GPS, basically cross-references the ECM to think the Busa is in 5th gear when it really is in 6th. My understanding is, the factory ECM is programmed that in 6th gear the limited is two fold, one at 186mph (a product of the European GUV from 1999 that decided it was unnecessary to have ANY vehicle sold to the public capable of speeds beyond 186...bastages) and one limiter set at 10,200rpms for 6th gear only (10,600 for 1-5 gears).
Well, back to my regularly scheduled programming.
Charlie
As far as I know, the recent Euro Busas are running an O2 sensor so they operate in closed loop mode during constant throttle conditions. They go open loop during warm up and during large or rapid throttle openings
I have 3 bikes, a 04 Busa, 05 VN2000 and an 06 FZ1. The VN2000 and FZ1 both have sub throttle plates. Sub throttle plates are used primarily to meet emissions and also to provide "drivability". The drivability part is being used in the marketing hype by manufacturers to justify their use. Many new bikes are going to need either sub throttle plates or drive by wire like the new R6/R1 to meet the newer emissions. The new 07 GSXR1K has them and the new Busa probably will too. Better get used to them and what mods work on them.
There are a number of mods to try and alter the operation of the sub throttle plates. Some people choose to remove the plates and use a PC3. On bikes with gear sensors, a "TRE" may work.
On my FZ1, which Yammi chose to emasculate with crappy software, I added a "Tweaker" circuit between the sub Throttle Position Sensor and the ECU. The circuit alters the voltage versus position output from the sensor. My low end performance improved a bunch with this simple mod. I am going to do the same to my VN2000 and see what it yields.
I have 3 bikes, a 04 Busa, 05 VN2000 and an 06 FZ1. The VN2000 and FZ1 both have sub throttle plates. Sub throttle plates are used primarily to meet emissions and also to provide "drivability". The drivability part is being used in the marketing hype by manufacturers to justify their use. Many new bikes are going to need either sub throttle plates or drive by wire like the new R6/R1 to meet the newer emissions. The new 07 GSXR1K has them and the new Busa probably will too. Better get used to them and what mods work on them.
There are a number of mods to try and alter the operation of the sub throttle plates. Some people choose to remove the plates and use a PC3. On bikes with gear sensors, a "TRE" may work.
On my FZ1, which Yammi chose to emasculate with crappy software, I added a "Tweaker" circuit between the sub Throttle Position Sensor and the ECU. The circuit alters the voltage versus position output from the sensor. My low end performance improved a bunch with this simple mod. I am going to do the same to my VN2000 and see what it yields.
Thanks for the info, Tommy. OK if I point out a few things? Notice the computer setting an open loop for the upper performance band.
The subthrottle system is a computerized CV (constant velocity) power delivery component. The sub's slow the power down. When you installed the Tweaker, all you did was set the fail-safe. Sounds like the same effect a computer bike I'm familiar with does = opens subs by default mode.
If you've been following the fuel injection system remarks, you can identify the subs have nothing to do with emissions. The sensors and rpm spin; do not care how many plates are lined up behind the throttle bodies main plates. You're right, it's a driveability helper.
Fuel tank (gas) vapor is routed to a charcoal canister. Throttle bodies are vented to suck the vapor from the canister. The exhaust pipes are more (emissions) honeycombed internally. The crankcase venting is routed for emissions. The block-off plates are emission related to feed air into the exhaust to clean up emissions.
Subthrottles are not emission related. Subs are used to counter the abrupt response the tweaker exposed inside the ECM.
The subthrottle system is a computerized CV (constant velocity) power delivery component. The sub's slow the power down. When you installed the Tweaker, all you did was set the fail-safe. Sounds like the same effect a computer bike I'm familiar with does = opens subs by default mode.
If you've been following the fuel injection system remarks, you can identify the subs have nothing to do with emissions. The sensors and rpm spin; do not care how many plates are lined up behind the throttle bodies main plates. You're right, it's a driveability helper.
Fuel tank (gas) vapor is routed to a charcoal canister. Throttle bodies are vented to suck the vapor from the canister. The exhaust pipes are more (emissions) honeycombed internally. The crankcase venting is routed for emissions. The block-off plates are emission related to feed air into the exhaust to clean up emissions.
Subthrottles are not emission related. Subs are used to counter the abrupt response the tweaker exposed inside the ECM.
First let me state I only have a rudimentary understading about EFI. I'm sure there are plenty on the board who could point out my mistakes.
The FZ1 and Busa use an older form of EFI called Speed Density, SD. The MAP sensor, Temp sensors and RPM are used to infer input air density. Any modification that alters intake vacumn, will screw up the accuracy in determining air density. A more accurate way to determine air density is to use a Mass Air Flow, MAF sensor like most cars which can measure air density and temperature directly. Cars also have MAP sensors and can alternate between SD and MAF controlled EFI depending on conditions or sensor failure. The addition of an O2 sensor improves emissions by keeping the CAT converter "happy" and also fuel economy. It is only used during steady state driving.
The MAP sensor is the primary input in an SD EFI in determining how much fuel to add. The Throttle Position Sensor, TPS has secondary control over how much fuel is added. The MAP sensor measures the vacumn change that occurs when you open the main throttle plates. The TPS is used to sense static throttle and sudden throttle changes.
If you alter the MAP sensor output by running it at a different voltage, adding an external circuit or by altering manifold vacumn, the ECU will change the fueling. Most vehicle also measure Atmospheric pressure and compare it to manifold pressure. If you alter the MAP output too much, you will probably throw a code since the ECU will flag a problem.
If the bike is stock, the ECU can infer air density with reasonable accuracy. A US Busa does not have to meet stringent emissions rules. If you stab the throttle, the ECU will sense the main plates opening via the MAP sensor and TPS and dump a lot of fuel. The MAP info will dominate. Out the tailpipe will come a lot of noxious emissions.
In any EFI system, there are multiple software tasks running. The tasks are interdependant on each other and sensor inputs. The sub Throttle Plates are primarily used by the ECU to directly effect manifold vacumn. If the MAP output change is "attenuated" when you stab the throttle due to the sub plates being closed, the software task using the MAP sensor will not dump more fuel. This allows the manufacturer to control emissions regardless of your wrist input. It also won't allow a bog due to a too lean condition. The engine slowly spools up. This allows manufacturers to claim the sub-throttle plates improve "drivability".
My circuit does not allow the ECU to "choke off" the input via the sub plates. The plates also open at a faster rate. All that is being done is too fool the ECU into thinking the plates are in the position commanded. Since the plates are not closed, the MAP now senses without "attenuation" the main plates being opened. This mod may not work on all bikes with sub plates. Any bike that has a throttle response improvement with the sub plates removed would probably be a candidate.
In the future, do not be suprised that the EFI on a 4 cyl bike to include more than 1 MAF sensor and multiple O2 sensors as well as a fly by wire throttle. That is probably the only way to meet emission rules. The ECU will probably swiitch to limp home mode if any tampering is done.
The FZ1 and Busa use an older form of EFI called Speed Density, SD. The MAP sensor, Temp sensors and RPM are used to infer input air density. Any modification that alters intake vacumn, will screw up the accuracy in determining air density. A more accurate way to determine air density is to use a Mass Air Flow, MAF sensor like most cars which can measure air density and temperature directly. Cars also have MAP sensors and can alternate between SD and MAF controlled EFI depending on conditions or sensor failure. The addition of an O2 sensor improves emissions by keeping the CAT converter "happy" and also fuel economy. It is only used during steady state driving.
The MAP sensor is the primary input in an SD EFI in determining how much fuel to add. The Throttle Position Sensor, TPS has secondary control over how much fuel is added. The MAP sensor measures the vacumn change that occurs when you open the main throttle plates. The TPS is used to sense static throttle and sudden throttle changes.
If you alter the MAP sensor output by running it at a different voltage, adding an external circuit or by altering manifold vacumn, the ECU will change the fueling. Most vehicle also measure Atmospheric pressure and compare it to manifold pressure. If you alter the MAP output too much, you will probably throw a code since the ECU will flag a problem.
If the bike is stock, the ECU can infer air density with reasonable accuracy. A US Busa does not have to meet stringent emissions rules. If you stab the throttle, the ECU will sense the main plates opening via the MAP sensor and TPS and dump a lot of fuel. The MAP info will dominate. Out the tailpipe will come a lot of noxious emissions.
In any EFI system, there are multiple software tasks running. The tasks are interdependant on each other and sensor inputs. The sub Throttle Plates are primarily used by the ECU to directly effect manifold vacumn. If the MAP output change is "attenuated" when you stab the throttle due to the sub plates being closed, the software task using the MAP sensor will not dump more fuel. This allows the manufacturer to control emissions regardless of your wrist input. It also won't allow a bog due to a too lean condition. The engine slowly spools up. This allows manufacturers to claim the sub-throttle plates improve "drivability".
My circuit does not allow the ECU to "choke off" the input via the sub plates. The plates also open at a faster rate. All that is being done is too fool the ECU into thinking the plates are in the position commanded. Since the plates are not closed, the MAP now senses without "attenuation" the main plates being opened. This mod may not work on all bikes with sub plates. Any bike that has a throttle response improvement with the sub plates removed would probably be a candidate.
In the future, do not be suprised that the EFI on a 4 cyl bike to include more than 1 MAF sensor and multiple O2 sensors as well as a fly by wire throttle. That is probably the only way to meet emission rules. The ECU will probably swiitch to limp home mode if any tampering is done.
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