Question TRYING to solve the snatchy throttle

[Piggy]

So I’ve been giving some thought to the throttle response issues that some experience. From what I gather, the real complaint is a delayed response off idle. I don’t hear that the problem exists from part-throttle roll-ons. Further, the issue doesn’t necessarily present itself while the bike is in neutral. This suggests that the ECU is using either speed related data or gear position to change from a “neutral” map to an “in-motion” map.

There are two parts of the EFI system; The Fuel Delivery System and the Control System. Hear are the parts that make up each:

Fuel Delivery System

• Fuel pump
• Pressure regulator
• Fuel injector
• Throttle body

Control System

• Engine Control Unit
• Throttle position sensor
• Intake air pressure sensor
• Coolant temperature sensor
• Crankshaft position sensor
• Intake air temperature sensor

Does anyone notice what is missing from these lists? Speed or gear-position data.


For those of you that have this problem, can you conduct some tests for me?

Test 1. Confirm/Disprove that the delayed throttle exists in neutral.

Test 2. While in motion and the problem is present, determine if the delay is a result of throttle position, or time.

Test 3. Confirm/Disprove that the delayed throttle exists only from an idle position, not a part throttle roll-on.

Test 4. Confirm/Disprove with the bike in motion, but in neutral, that the delayed throttle exists

Test 5. Confirm/Disprove with the bike in motion, in gear but with the clutch engaged, that the delayed throttle exists

Test 6. Confirm/Disprove that the throttle delay issue is NOT present in 6th gear. (added from post #71).


Depending on your inputs we can determine what ADDITIONAL input the ECU reads besides the noted Control System inputs. This problem could be as simple as a speed sensor or a faulty neutral/gear position switch. If one of the above sensors has a fault, it registers a fault code, however if other data is being used no fault codes exist for the failure.

I will try and do this 6 test list later this week if I can

 

[Morelius]

good day everyone! Wow I totally missed all these replies since my last.. .been a long winter with suspension upgrades and I've ridden the bike only twice since going to DynoJet HQ in UK and getting an on the dyno tune. The bike rips and has more power all over the range but that issue is still present.

It is well described by a few of you here... the throttle goes from 0-5% in one step if you like...

Things I have done;

AIS delete.
Perfect throttle cable adjustment.
TPS adjustment (and replacement)
New chain and sprockets and cush drive. Chain tension changes make no difference.
Balanced the throttle bodies
Tested fuel pressure
...the list goes on.

It is the "dreaded Yamaha fuel cut" issue as descibed and if I cannot find a solution this year (despite throwing a grand at the bikes suspension upgrades)... I will be looking to get a different bike next year

One chap here described well how scary it is in 2nd and 3rd when leaning over and it hits hard despite focusing on smooth throttle input. Once throttle open... say holding at 20%, then gently opening it and its not there...

Its from 0% to throttle open... injection delay.

The resistors solution above I am very curious about but I'd like to know what it actually does... what is it tricking the ecu into thinking??

Tricks the ecu to think there is still suction or slight pressure in the airbox and therefore it does not cut fuel. There is a lot of info if you want. Just google "zady5". It works. I was very close to sell the bike til I tried it.

I did the 6 test. Worth nothing. You should go straight to the mod.

 

[Piggy]

Tricks the ecu to think there is still suction or slight pressure in the airbox and therefore it does not cut fuel. There is a lot of info if you want. Just google "zady5". It works. I was very close to sell the bike til I tried it.

I did the 6 test. Worth nothing. You should go straight to the mod.

So the ECU cuts fuel when it sees vac at the manifold but 0% tps and idle switch not engaged?...

zady5 the original thread on the FZ1 forum really explains all this... wish I had found it sooner... he describes perfectly what i could "see" in my head the ecu was doing and it explains why a PC/dynojet remap will not solve it as the ECU is using the map sensor for fuel on/off cut below 18% on the fz1.. .I cant imagine they changed that much for the fz6

 

[Morelius]

So the ECU cuts fuel when it sees vac at the manifold but 0% tps and idle switch not engaged?...

zady5 the original thread on the FZ1 forum really explains all this... wish I had found it sooner... he describes perfectly what i could "see" in my head the ecu was doing and it explains why a PC/dynojet remap will not solve it as the ECU is using the map sensor for fuel on/off cut below 18% on the fz1.. .I cant imagine they changed that much for the fz6

Try it... You have nothing to lose

 

[Lukenzo]

good day everyone! Wow I totally missed all these replies since my last.. .been a long winter with suspension upgrades and I've ridden the bike only twice since going to DynoJet HQ in UK and getting an on the dyno tune. The bike rips and has more power all over the range but that issue is still present.

It is well described by a few of you here... the throttle goes from 0-5% in one step if you like...

Things I have done;

AIS delete.
Perfect throttle cable adjustment.
TPS adjustment (and replacement)
New chain and sprockets and cush drive. Chain tension changes make no difference.
Balanced the throttle bodies
Tested fuel pressure
...the list goes on.

It is the "dreaded Yamaha fuel cut" issue as descibed and if I cannot find a solution this year (despite throwing a grand at the bikes suspension upgrades)... I will be looking to get a different bike next year

One chap here described well how scary it is in 2nd and 3rd when leaning over and it hits hard despite focusing on smooth throttle input. Once throttle open... say holding at 20%, then gently opening it and its not there...

Its from 0% to throttle open... injection delay.

The resistors solution above I am very curious about but I'd like to know what it actually does... what is it tricking the ecu into thinking??

It raises lower side of MAP signal a bit so ecu sees air being drawn (or rather doesn't see rapid throttle close) in and doesn't shut down fuel all the way down (keeps injectors open for longer) after you close a throttle, it's like a buffer between accel and decel maps. Fuel cut still happens but it's in lower rpm's and does not bother me much. I noticed some weird fueling on cold engine (too rich) and it probably does change a/f ratio out of spec in some rpm's even on hot engine, but as long as it's on rich side and below like 6K rpm it should be fine.

 

[Piggy]

AN UPDATE!!!! FIXED (almost)

Lets make some things clear here... I have not just stabbed in the dark in this long process... I have gone through everything twice if not three times.

The list of things replaced, tested or tried;

• Chain, sprockets, cush drives, wheel bearings, trailing arm bearings.
• TPS (position and tested), throttle balancing, throttle cable (adjust and test)
• AIS system blanked off. Timing changes. CO2 settings changed along with airbox mod and exhaust.
• Piggyback plug in booster plug thingy (what a bodge and waste of money that is,sent it back)
• Biggest expense; Power commander and went to DynoJet HQ in the UK and had a rolling road custom tune...

None of it made a difference. (they all made a difference of course, to be pedantic, but not to the delay)

These DO have it and yes, it IS common. I have had SO many private messages, post replies and youtube comments from those who assumed it was just normal or a qwerk or they'd tried things and given up/lived with it/sold the bike. Like with so many other common issues with cars/bikes/washing machines etc, just because 100% of people dont post or ring the ITV for an exclusive about it, doesnt mean it isnt common.

Those who argue aabout it (and they seem so confident they are right) and say its not an issue and its not common...
I can only assume two things; they ride so poorly that the jerky input isnt noticable or they are fortunate to have a fazer that doesnt do it (some do not, it seems S2 are more common for it than S1, IE, almost ALL s2 riders mention it)

Which is why I would not give up on finding something that would work. I have found on track too, the faster you go, the more dangerous it can get, mid corner, rolling on the throttle and its a big jerk of power input despite the actual throttle being smooth....

here are a couple of videos to get up to date... the fix was the Zady5 fix... video for that comes out next week and I will post it and with a link to his forum post and info.

...watch this space....

 

[Gary in NJ]

Those who argue aabout it (and they seem so confident they are right) and say its not an issue and its not common...
I can only assume two things; they ride so poorly that the jerky input isnt noticable or they are fortunate to have a fazer that doesnt do it (some do not, it seems S2 are more common for it than S1, IE, almost ALL s2 riders mention it)

This bothers me. I can see that you are passionate about solving this issue, but there is no need to insult people just because they don't experience the same issue as you. Couldn't you simply state "not everyone will experience this issue, but for those that do I will continue to identify a resolution"'

 

[Piggy]

This bothers me. I can see that you are passionate about solving this issue, but there is no need to insult people just because they don't experience the same issue as you. Couldn't you simply state "not everyone will experience this issue, but for those that do I will continue to identify a resolution"'

I'm sorry you find it bothers you. Welcome to people being honest about facts. I'm not here to tickle people's ears with things they want to hear to make them feel better when a possible solution to improve their riding or ride is available.

If you think you ride poorly/have not considered your poor throttle control and are offended by me suggesting this... Then maybe improve your throttle control? It would improve your joy on the bike and safety in control of the bike.

If you don't think you ride poorly or don't have poor throttle control, then that part doesn't apply to you, surely?

As such, the second part of my sentence would apply? No? I'm assuming you didn't read after the bit that bothers you as you suggest I add a part about it "not being experienced by everyone", yet I put exactly that.

I've seen dozens and dozens of riders mention how jerky their modern injection bike is and then I watch them ride and it's all in their wrist. I first assumed the same of my riding when I experienced this issue on the Fazer, took advanced schools and riding classes to get as naturally smooth/automatically smooth as much as I could.

Improved throttle control by the rider is my No1 fix for a majority of riders who experience this snatchy throttle issue on a variety of different bikes.

I'm not sorry one of my solutions bothers you.

I don't take it personally and ask you try to do the same as I have no idea of your personal experience with snatchy throttle control or response.

I am being direct, informative and as helpful and honest as I can be.

I'm really stumped as to why you think I'm being insulting to riders who cannot ride very well?!? If they can't ride very well, they should be told, it's their life on the line everytime they ride poorly. If I beat around the bush I find such riders just don't get it.

 

[Piggy]

 

[Dennis.vd.holly]

Where did you get the plugs for the loom? Can't find that anywhere

As Jack sparrow would say: GOT IT!

 

[Piggy]

Where did you get the plugs for the loom? Can't find that anywhere

As Jack sparrow would say: GOT IT!

Google search was my saviour.

In the zady5 thread he gives some parts numbers I think pal.

By the second part of your message... Just checking you DID get them ok?

 

[Dennis.vd.holly]

Here is how to do the Zady5 mod adapted to the fz6 wiring. First locate the IMAP sensor. Under the tank and right side of the bike:

View attachment 75709

You will need x4 1N4007 diodes. welded in serial conection and a pair of denso type conectors. model 174359 and 174357. Should like something like these:


View attachment 75711 View attachment 75712

Then follow the diagram and assemble. It's in spanish but you can translate it

View attachment 75713

You should end with something like this:

View attachment 75714

Disconect the original harness and put that shit in between.

Enjoy.

I did the pigtail and can't get it to function without throwing an engine light fault. Did you do this on an S2 or S1? And did you get the engine light as well? I've checked everything from wire colors to polarity and voltage, it all pans out. It appears to run fine, but that light will not go out.

 

[Piggy]

I did the pigtail and can't get it to function without throwing an engine light fault. Did you do this on an S2 or S1? And did you get the engine light as well? I've checked everything from wire colors to polarity and voltage, it all pans out. It appears to run fine, but that light will not go out.

S2.
I believe it works for S1 and S2.

I think I replied to your post or messages elsewhere but good to clarify here on this thread too.

I would think it important to read the code to understand why its throwing a fault first of all. Lots of people have done this mod in the past and most recently, your the first to mention this issue.

Now, the first is the first and it could be the first of MANY... there has to be a first with any issue... BUT it does seem odd that everyone else is fine. . . ?
Check the code.
Triple check connections and pins. Only takes one pour solder joint or pin connector to cause an issue.

 

[francesco21]

I have done the mod on my S2.

For Dennis post above, I also had an engine fault code on the first try (I think it was fault code number 13).

After some research, there was a false contact in my assembly.
And after correction, the engine fault code disappeared ; so, no engine fault code on S2 if the assembly is correct, I am sure of that.

Effectively, I feel that things are improved on on/off and off/on throttle transitions.
And therefore gear shift seems also to be improved.

Thank you Piggy for all the work and the report on the forum of this great bike !

Anf for information, here are links to 2 others Youtube videos where the mod is also explained (in addition to Piggy's one).

 

[Dennis.vd.holly]

I have done the mod on my S2.

For Dennis post above, I also had an engine fault code on the first try (I think it was fault code number 13).

After some research, there was a false contact in my assembly.
And after correction, the engine fault code disappeared ; so, no engine fault code on S2 if the assembly is correct, I am sure of that.

Effectively, I feel that things are improved on on/off and off/on throttle transitions.
And therefore gear shift seems also to be improved.

Thank you Piggy for all the work and the report on the forum of this great bike !

Anf for information, here are links to 2 others Youtube videos where the mod is also explained (in addition to Piggy's one).

In my case it was the sketchy AliExpress connector. When plugging it in, it pushed one of the pins up. It sprung back on removal. Fixed that this week and works now.

 

[Cocoloco]

I'll just share some of my experience regarding this. Been through tps sparkplugs and coils, advanced rotor seems to help a bit

So i decided to replace my fuel regulator with a new one from toyota corolla i believe its higher about 40psi than the stock 36psi
I adjust my CO values lower
With aftermarket exhaust

This solved my problem even when its hot or cold no more hesitation
I gained confidence cornering.

 

[Dennis.vd.holly]

You must have had a heck of a lot more hesitation than I had
Been running this cheapest mod I've ever done on any vehicle and already have no hesitation left