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WRF-Rowdy

WR450F 2012 real time AFR

27 posts in this topic

A couple months ago I played with the stock euro YAMAHA O²sensor and found

stoichometrically perfect mixture to occur only at a CO setting of -26 :

http://www.thumpertalk.com/topic/1143864-efi-co-value-fi-diagnostic-vs-af-ratio/

 

 

I finally got the WideBand AFR sensor kit http://www.ebay.at/itm/APSX-V2-Anti-Glare-D2-Digital-Wideband-O2-AFR-Gauge-Sensor-Kit-Black-GREEN-/271971970568?hash=item3f52caee08:g:gtAAAOSwVL1WBWjY

I swapped back to the stainless steel muffler and euro O²sensor header

20160128_100957_50.jpg

 

It comes complete with a Bosch LSU 4.2 wide band multi fuel O² sensor

20160128_102836_50.jpg

 

I decided to siphon some 12V off the headlamps parking light:

20160128_131310_50.jpg

 

drove around to heat up the engine and was very amazed what AFR readings the display did show,

remember stoichometric AFR is 14.7, any lower number means rich, higher means lean.

at my current CO setting of -18 the AFR was 12.5!

maxxing out the CO setting to -30 I got an AFR of 13.7, still rich :jawdrop:

 

Here is the quick and dirty idle mixture AFR check video:

 

 

I find that rather hard to believe, here are some other findings:

Switching off ignition while riding instantly had the AFR jump to 19 (max reading)

Heavy engine braking at high rpms yields AFR 15, switching off the ignition (kill switch) gives 19, and switching back on 15 again.

Normal cruising shows AFR to be 12.5 !

Even moderate acceleration has the AFR drop to 10, slightly backing off a crack restores 12.5

 

Considering that installation &%$#@!ups like header sealing issuses etc would lead to lean readings

and the immediate snap to AFR 19 when switching off ignition (100% air in the header)

would insinuate my rich readings to be correct.  :naughty:

 

Anyone got an idea why engine braking (with presumed EFI fuel shutoff)

repeatedly reads 15 and not the 19 I see when killing ignition?

Why does the EFI still inject fuel during engine braking?

 

This is a research in progress, these values seem way on the rich side.

Maybe I've change the fuel type the sensor is using, I'll check and post back in the thread.

 

edit: I think I'll switch to lambda setting,

check out the table Air/Fuel (A/F) Ratios of Common Fuels at the end

http://www.hotrod.com/how-to/engine/1307-wideband-oxygen-sensor/

Edited by WRF-Rowdy

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How about reporting what you get with high positive numbers?

 

Are you saying all your previous claims may possibly be wrong?

Edited by AtomicGeo

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How about reporting what you get with high positive numbers?

 

Are you saying all your previous claims may possibly be wrong?

Au contraire, my previous claims are heavily supported by the numbers,

they might have been on the conservative side, even.

 

BUT

As you can see in the vid even with a CO = -30 (maxxed out) 

I get a reading below 14.7 that means CO = - 30 is still rich idle mixture. :jawdrop:

 

if you recall my checks with the narrow band sensor at

http://www.thumpertalk.com/topic/1143864-efi-co-value-fi-diagnostic-vs-af-ratio/

there is a contradiction:

 

if the WB sensor sez AFR=13.5 (slightly rich) at CO= -30

and the NB sensor found true lean at CO= -26 one of them must be lying :devil:

(or water temp was still too low, so the ECU still did cold start enrichment? :(

 the narrow band measurements were done at an OAT of 35°C in summer)

 

 

The only occasion where I currently get to see an AFR number of 14 to 15 is

at very slight throttle openings above the idle stop, like when very gently taking off at a 4-way stop intersection.

 

This might explain the "guys, open the throttle a tiny bit for starting" mantra propagated by Bass Mechanic:

Cracking the throttle a tiny bit is the only way to lean the normally way too rich idle mixture some people are driving around with.

Exactly what I was preaching:

Had they set the CO right (way down negative) they wouldn't have to lean the mixture for starting by opening the throttle.

 

 

Everywhere else she's running rich, and when I blip the throttle at mid rpms for a short acceleration jolt

AFR drops down to below 11 which is extremely rich!

I definitely have to check what PowerTuner mapping I currently running,

appears to be waaaayy too rich, because if you regard the table near the bottom of that page

http://www.hotrod.com/how-to/engine/1307-wideband-oxygen-sensor/

anything below an AFR of 12.5 is waste of fuel :banghead:

edit:

ign all zeroes, fuel mapping at above observations was
-2  0 +4
-2 -2 -2
-2 -2 -2 

findings:

=> so the ECU does have a hefty acceleration enrichment programmed in

=> "leanest" idle mixture is with CO at -30 resulting in an AFR of 13

=> opening the throttle slightly as idle sees AFR rise from 13.5 to 14/15 (leaning!)

=> -2 fuel mapping runs very rich, even more soe when accelerating

Edited by WRF-Rowdy

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I think mine runs lean under engine braking too.  There's a certain RPM range where it always pops, probably exhaust reversion.  If I crack the throttle slightly it pops more; must be that spot you're talking about where the fueling doesn't really kick in yet.  If I had a power commander I could probably tune that out.

 

Have you tried advancing the timing to see what effect it might have on AFR?  You might be able to get a more complete burn.  I imagine most of the off the shelf maps would be conservative on timing.

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I believe, if you adjust the TPS resisistance higher, you can 'trick' the ecu to be in the second map (partial throttle) sooner, rather than in the first map (idle) allowing you to have more adjustment range.

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Have you tried advancing the timing to see what effect it might have on AFR?  You might be able to get a more complete burn.  I imagine most of the off the shelf maps would be conservative on timing.

 

Well my big plan is:

 

1) get the fuel mixture right:

 

no richer then 12.5 and  no leaner than 13.5 everywhere

except for cruising (bottom row of PowerTuner) where Id like to see 15-16 (max economy)

 

 

2) advance ignition until knocking then back off a bit.

 

That should be the perect mapping whatever weird the numbers will be,

combining efficiency at 1/8th throttle with max. power at WFO.

 

 

3) If that would be more than I'd like to handle, retard ignition only.

 

So I'll certainly have to turn my attenting to timing somday this year.

For me that's always been a very oblique but dangerous area.

Personally I see a messed up ignition timing as much more dangerous that "lean" on the PT,

because with too andavanced a timing you knock your crank to pieces and

with too late a spark you'll looes 50% horse power.

(I'll never forget a buddy's WR426F where the CPU has died:.

  In "limp home mode" she'd fired right up as usual first kick,

 but lacking any ignition advancing you'd be going 10mph WFO in 2nd.

 outright scary.)

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As I have stated to you at least 100 times already and apparently you are not comprehending or refuse to believe The reason the bike starts easier with a slightly open throttle is because a fully closed throttle limits the amount of compression your able to get combined with the use of a decompressor mechanism. Opening the throttle slightly allows more air in the cylinder, restores the compression significantly (despite the de compressor) and with the additional air pressure in the cylinder makes starting easier.

Your bike starts easy without cracking the throttle because you modified the decompressor pin when you installed the YZ cam and I am pretty sure you live at a lower elevation than most people who are having problems.

I suspect that the mixture goes leaner off idle because either the ecu is changing maps from idle to off idle or the TPS may need a slight adjustment.

It is possible that your readings are on the rich side because your AFR gauge and sensor may not be grounded correctly. I had the same issue on a supercharged truck I had installed gauges on once upon a time

And even if my bike is running rich and the gauge is accurate, who cares?

I used to be OCD like you about stuff like this but in the bigger picture, the bike runs great! Why go to all this trouble? Why put all that crap on your bike?

How about you find yourself a nice trail and just ride the damn thing?

I'm heading out this next week and I'm going to enjoy my new yz450fx I loaded one of the maps I found here on TT which added some timing and fuel to my tune. The bike hauls ass! I can pull wheelies in 4th gear!

And I couldn't give 2 shits what my AFR is!

Now the tune on my 6.2 Sierra with a supercharger, that is a totally different story!

On my bike, I can get 70 miles out of a tank! More than enough range for me. When I ride I pay attention to the terrain, improving my skills and most importantly having an AWESOME TIME riding. I take my bike out to relieve the stresses of life and enjoy the time with my friends, forget about work enjoy the scenery and the very last thing on my mind is "is my AFR too rich? Is it stoic? Is it not exactly perfect?"

WHO CARES!!

You know what? The ONLY time I worry about my air fuel ratio is when I fly airplanes! If you've ever been in one you would note that even the fuel injected engines require you to manually adjust the fuel flow from startup to cruise. Because in an airplane you change altitude all the time, you consequently have to change the fuel flow.

In an airplane we use cylinder head temperature on an air cooled engine to determine if we are running too lean or rich. Then to make matters worse, for fuel economy reasons you can run the engine what's called "lean of peak" meaning you run the engine lean to the point the cylinder head temp peaks, then lean it more until the temperature drops another 50 degrees lean of peak. At this point the engine is running very lean, so lean that your on the edge of stalling the engine! "The worry you would be experiencing at this point might just put you in a state of panic!"

I could just imagine the total state of panic you would find yourself in if you were a pilot because airplanes don't have any AFR gauges!!! Imagine that! Can you believe that an airplane who's engine running so perfectly to keep it aloft and purring like a kitten has no means of keeping the AFR perfectly stoic and a fuel mixture knob that you can pull and push a distance of about 4 inches would drive a guy like you completely insane not knowing if your too rich or too lean! Your engine might not be making the maximum Hp or getting the best fuel economy!

That would literally eat you alive I can see it now...

When I fly I need to make sure of 2 things, 1 engine is running smoothly, 2 is it rich enough while I'm doing my approach to land that if I have to abort the landing and go around again that it won't stall if I need full power when I abort. If I am in a carburetor plane do I have carb heat on and how much too rich will that affect my setting at this altitude?

You see the range of fuel ratios can be between 11-16 and still keep the engine running smoothly and making good power.

Are you working for the EPA or something?

Or are you just the nerdy type with a heavy dose of OCD mixed in?

Dude! You going to drive yourself bonkers and go broke looking for that last bit of performance and fuel economy that a dirt bike simply was never meant to have!

Now that you've come back to reality.. Trust me the AFR ratio between lean or rich doesn't make that much difference for performance especially on a WR and most importantly I'm sure at your skill level you probably just putt putt the thing around on a trail or a road it seems where you never even come close to using half the power the bike has anyway!

Try this.. Put your tools away.. Forget about fuel ratios, enjoy the fact your bike starts up on the first push of the button. Go find a trail and ride your bike and just enjoy it. Let all your worries melt away!

Lmao!

Edited by Bass Mechanic

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you know having thought about it for a bit. i am not at all surprised the AFR is rich. makes sense with the compression ratio all the way up to 12.3:1 and the fact the exhaust runs so close to the plastic and other parts i am surprised it stays as cool as it does.

i bet if you leaned it out to 14.7:1 you'll end up with detonation and likely an exhaust so hot it melts the side panel off the bike.

i am also certain that the yamaha engineers decided that if your going to sell an programmable ECU and a "power tuner" all it takes is for some back yard mechanic who thinks they know a lot about engines to discover online that you can get maximum power and torque out of an engine by leaning out the mixture and advancing the timing. and before you know it you've got a whole host of people complaining online that bikes are catching fire, engines are failing and give your brand a really bad reputation!

yep i am sure the engineers designed the bike rich and retarded the timing so that if you set everything at full advance and full lean your still able to make the bike run with some degree of safety margin.

the tuner changes the fuel 1 think 1% fuel for every setting and i think .5 degrees timing for every setting if i remember correctly.

so that means you can only lean it out 9% which might put it close to stoic. on the rich side 9% more fuel wont hurt anything except make the bike run cooler and sluggish.

makes perfect sense now!

 

on second thought, you should definitely see what you can do to get that mixture spot on! and send us some pictures on a hot day after you've ridden in the woods for a couple hours and up some gnarly hills.

that might be worth a good laugh!  :p

Edited by Bass Mechanic

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As I have stated to you at least 100 times already and apparently you are not comprehending or refuse to believe The reason the bike starts easier with a slightly open throttle is because a fully closed throttle limits the amount of compression your able to get combined with the use of a decompressor mechanism. Opening the throttle slightly allows more air in the cylinder, restores the compression significantly (despite the de compressor) and with the additional air pressure in the cylinder makes starting easier.

Your bike starts easy without cracking the throttle because you modified the decompressor pin when you installed the YZ cam and I am pretty sure you live at a lower elevation than most people who are having problems.

I suspect that the mixture goes leaner off idle because either the ecu is changing maps from idle to off idle or the TPS may need a slight adjustment.

It is possible that your readings are on the rich side because your AFR gauge and sensor may not be grounded correctly. I had the same issue on a supercharged truck I had installed gauges on once upon a time

And even if my bike is running rich and the gauge is accurate, who cares?

I used to be OCD like you about stuff like this but in the bigger picture, the bike runs great! Why go to all this trouble? Why put all that crap on your bike?

How about you find yourself a nice trail and just ride the damn thing?

I'm heading out this next week and I'm going to enjoy my new yz450fx I loaded one of the maps I found here on TT which added some timing and fuel to my tune. The bike hauls ass! I can pull wheelies in 4th gear!

And I couldn't give 2 shits what my AFR is!

Now the tune on my 6.2 Sierra with a supercharger, that is a totally different story!

On my bike, I can get 70 miles out of a tank! More than enough range for me. When I ride I pay attention to the terrain, improving my skills and most importantly having an AWESOME TIME riding. I take my bike out to relieve the stresses of life and enjoy the time with my friends, forget about work enjoy the scenery and the very last thing on my mind is "is my AFR too rich? Is it stoic? Is it not exactly perfect?"

WHO CARES!!

You know what? The ONLY time I worry about my air fuel ratio is when I fly airplanes! If you've ever been in one you would note that even the fuel injected engines require you to manually adjust the fuel flow from startup to cruise. Because in an airplane you change altitude all the time, you consequently have to change the fuel flow.

In an airplane we use cylinder head temperature on an air cooled engine to determine if we are running too lean or rich. Then to make matters worse, for fuel economy reasons you can run the engine what's called "lean of peak" meaning you run the engine lean to the point the cylinder head temp peaks, then lean it more until the temperature drops another 50 degrees lean of peak. At this point the engine is running very lean, so lean that your on the edge of stalling the engine! "The worry you would be experiencing at this point might just put you in a state of panic!"

I could just imagine the total state of panic you would find yourself in if you were a pilot because airplanes don't have any AFR gauges!!! Imagine that! Can you believe that an airplane who's engine running so perfectly to keep it aloft and purring like a kitten has no means of keeping the AFR perfectly stoic and a fuel mixture knob that you can pull and push a distance of about 4 inches would drive a guy like you completely insane not knowing if your too rich or too lean! Your engine might not be making the maximum Hp or getting the best fuel economy!

That would literally eat you alive I can see it now...

When I fly I need to make sure of 2 things, 1 engine is running smoothly, 2 is it rich enough while I'm doing my approach to land that if I have to abort the landing and go around again that it won't stall if I need full power when I abort. If I am in a carburetor plane do I have carb heat on and how much too rich will that affect my setting at this altitude?

You see the range of fuel ratios can be between 11-16 and still keep the engine running smoothly and making good power.

Are you working for the EPA or something?

Or are you just the nerdy type with a heavy dose of OCD mixed in?

Dude! You going to drive yourself bonkers and go broke looking for that last bit of performance and fuel economy that a dirt bike simply was never meant to have!

Now that you've come back to reality.. Trust me the AFR ratio between lean or rich doesn't make that much difference for performance especially on a WR and most importantly I'm sure at your skill level you probably just putt putt the thing around on a trail or a road it seems where you never even come close to using half the power the bike has anyway!

Try this.. Put your tools away.. Forget about fuel ratios, enjoy the fact your bike starts up on the first push of the button. Go find a trail and ride your bike and just enjoy it. Let all your worries melt away!

Lmao!

 

Erroneous

False

Inaccurate

Inflamatory

 

The real question is why are YOU so upset about another persons tuning journey?

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...yep i am sure the engineers designed the bike rich and retarded the timing so that if you set everything at full advance and full lean your still able to make the bike run with some degree of safety margin...

 

Not sure if sarcasm but I read on another forum that's exactly what they did.  Supposedly someone from yamaha said you won't blow it up with the power tuner no matter what numbers you enter.  I mostly ride on the street on 17s so too much power from a 450 isn't really a thing in my case

Edited by chu

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Not sure if sarcasm but I read on another forum that's exactly what they did.  Supposedly someone from yamaha said you won't blow it up with the power tuner no matter what numbers you enter.  I mostly ride on the street on 17s so too much power from a 450 isn't really a thing in my case

I can counter that profoundly:

Setting the PT fuel map to lean (e.g. "a mapping NOT reading rich everywere")

AND

andvancing the ignition WILL give you massive detonation at medium load

(accelerating on mountain road) BTDT!

 

So personally I'd estimate that lean fuel map + advanced ignition map will ruin your engine,

especially when (ab)using the bike on the road.

Edited by WRF-Rowdy

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I'd be surprised if every bike off the floor didn't run rich, its intentional...

 

If you want to make this worth your while put down a few bucks for a dyno session and seat tune the bike

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I'd be surprised if every bike off the floor didn't run rich, its intentional...

If you want to make this worth your while put down a few bucks for a dyno session and seat tune the bike

I think they run lean from the factory due to EPA, and that's why they run hot and are hard to start.

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I think they run lean from the factory due to EPA, and that's why they run hot and are hard to start.

I'm right with you here, have been thinking green sticker and what not but they are really running very rich.

On my WR idle is rich AFR-wise down to -26/-30 (depending on how/when I measured AFR)

But my european WR is fully de-restricted, complete with PowerTuner adjustable "racing-ECU".

In this configuration them WRFs do run rich everywhere in stock trim.

 

A couple months ago, I was trying to find a PowerTuner lean fuel mapping

and I had to use very negative numbers to see a "lean" AFR, see my post

http://www.thumpertalk.com/topic/1143752-efi-powertuner-maps-vs-af-ratio/page-2#entry12497115

 

One has to be very cautious not to active the builtin acceleration enrichment function,

e.g. even slightly opening the throttle will give you enrichment for ~2 seconds.

Currently when I'm coasting around I get  an AFR of 12.5, upon adding throttle it drops to 10.5!

 

So when whacking it WFO doing 40mph in 5th to test fuel mapping

you'd have to add rear brake to hold the rpms in the 3000 range for a couple of secs,

before you can see the AFR of the "top left" fuel map setting.

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I'm right with you here, have been thinking green sticker and what not but they are really running very rich.

On my WR idle is rich AFR-wise down to -26/-30 (depending on how/when I measured AFR)

But my european WR is fully de-restricted, complete with PowerTuner adjustable "racing-ECU".

In this configuration them WRFs do run rich everywhere in stock trim.

A couple months ago, I was trying to find a PowerTuner lean fuel mapping

and I had to use very negative numbers to see a "lean" AFR, see my post

http://www.thumpertalk.com/topic/1143752-efi-powertuner-maps-vs-af-ratio/page-2#entry12497115

One has to be very cautious not to active the builtin acceleration enrichment function,

e.g. even slightly opening the throttle will give you enrichment for ~2 seconds.

Currently when I'm coasting around I get an AFR of 12.5, upon adding throttle it drops to 10.5!

So when whacking it WFO doing 40mph in 5th to test fuel mapping

you'd have to add rear brake to hold the rpms in the 3000 range for a couple of secs,

before you can see the AFR of the "top left" fuel map setting.

I can't comment on the AFR as I only play with the power tuner and that is basically the extent of my tuning. I'm running the race ECU with full FMF exhaust and the FMF map, and I can tell it is quite rich.

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I think they run lean from the factory due to EPA, and that's why they run hot and are hard to start.

Maybe the Calif. green sticker version.  The de-restricted version with powertuner-ECU definitely runs rich:

 

Mine certainly did. The preowner rode and raced it that way for three years. :facepalm:

He never experienced push button in gear starts in that time because he had CO at stock zero setting.

Poor slob, thought it has to be that

he's got to get into neutral, release the clutch, reach for the knob, "and slightly pull it out, to eanble button e-starts"

 

He probably will tell anyone who asks him about the bike, that he'd liked it a lot, except for the faulty (in gear) e-starting when hot. :banghead:

 

These rumors damaging the reputation of a really perfect bike with perfect in-gear e-starts are the major reason

why I had to counter the wrong  hint/trick Bass Mechanic claimed to be necessary to easily e-start it.

It may be true that it helps the wrongly setup bike, but it positively is a clueless lie that "it has to be that way, that setting CO right won't help."

 

 

I know that for sure because I bought one of those "hard to e-start when hot bikes ".

I was pissed at the PITA when trying to e-start it in the woods.

I was relieved that setting CO right made the whole issue disappear.

I was even more happy that I manged to trim a YZ cam to exactly the same decomp properties as the stock WR cam

and thereby PRESERVED the perfect button-startability when transitioning from WR-cam to YZ-cam.

(Check out my posting on how to mimic WR decomp on a YZ cam, it was really easy:

http://www.thumpertalk.com/topic/1141940-wr450f12-how-to-grind-a-yz-cam-for-e-startability/)

Edited by WRF-Rowdy

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Maybe the Calif. green sticker version. The de-restricted version with powertuner-ECU definitely runs rich:

Mine certainly did. The preowner rode and raced it that way for three years. :facepalm:

He never experienced push button in gear starts in that time because he had CO at stock zero setting.

Poor slob, thought it has to be that

he's got to get into neutral, release the clutch, reach for the knob, "and slightly pull it out, to eanble button e-starts"

He probably will tell anyone who asks him about the bike, that he'd liked it a lot, except for the faulty (in gear) e-starting when hot. :banghead:

These rumors damaging the reputation of a really perfect bike with perfect in-gear e-starts are the major reason

why I had to counter the wrong hint/trick Bass Mechanic claimed to be necessary to easily e-start it.

It may be true that it helps the wrongly setup bike, but it positively is a clueless lie that "it has to be that way, that setting CO right won't help."

All the ones sold in America are the green sticker California tuned version I believe. Haven't messed with my CO yet.

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All the ones sold in America are the green sticker California tuned version I believe. Haven't messed with my CO yet.

But surely yours is de-restricted? Otherwise you'd be stuck with a 250lbs 12hp diesel pig. :goofy:

 

Noone over here in Austria rides the street legal closed loop O² sensor version.

Everyone wants the 40hp type complete with PowerTuner adjustable ECU.

 

But hey, if your bike starts in gear with one push of the button don't mess with the CO setting, it's already perfect. :thumbsup:

 

However if not, get the FI diag tool connected and try +/- 10, -/+20 and +/-30 and see how they affect in-gear e-starts. :devil:

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But surely yours is de-restricted? Otherwise you'd be stuck with a 250lbs 12hp diesel pig. :goofy:

Noone over here in Austria rides the street legal closed loop O² sensor version.

Everyone wants the 40hp type complete with PowerTuner adjustable ECU.

But hey, if your bike starts in gear with one push of the button don't mess with the CO setting, it's already perfect. :thumbsup:

However if not, get the FI diag tool connected and try +/- 10, -/+20 and +/-30 and see how they affect in-gear e-starts. :devil:

Yes, I've fully derestricted mine. I didn't know the Euro street models came with O2 sensors until reading this thread. I don't know much about FI and would think that all FI bikes need O2 sensors to work properly but I guess not. My bike is usually a 2 push starter, ocassionally it will fire right up on the first try but mostly not. What is interesting is when I kick it she goes on the first time every try when hot.

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Yes, I've fully derestricted mine. I didn't know the Euro street models came with O2 sensors until reading this thread. I don't know much about FI and would think that all FI bikes need O2 sensors to work properly but I guess not. My bike is usually a 2 push starter, ocassionally it will fire right up on the first try but mostly not. What is interesting is when I kick it she goes on the first time every try when hot.

It's a weird setup, using a closed loop Lambda sensor capable ECU to run in open loop mode, w/o any feedback regarding AFR she's producing, but apparently the accuracy of the MAP sensor combinend with TPS and a lot of test runs enabled YAMAHA to create mappings/algorithms that produce a very stable carburator impersonation.

 

Regarding hot start: That's exactly what I had to endure. Before taking the to me new bike onto one week of off road vacation to Italy, I "fine tuned" the CO setting some 5 notch towards rich, because I've read so on the net and wanted to improve hot start.

That week was a dreadful torture. Bike would mostly start on third(!) button stab or first kick in neutral.

I tried a lot of e-start procedures, including but not limited to rolling on the throttle, holding it open a tad like in TT600 times, blipping it etc.etc.

Buddy on 450EXC would shook his head at my sorry e-start attempts on my then new bike, courteously not commenting on YAMAHA vs. e-start.

 

Things became happy again only after returning home and playing with the FI diagnostic tool in the direction of what I then regarded as "crazily lean".

Today I know better, and in hindsight find it amazing, that the bike back then did startup by button press at al.

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