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I just wanted to know if anybody had the issue with your bike when just cruising down the street. My bike seems to want to pull or coast. There really isn't no in between. This happens when cruising low speeds in residential areas.
 

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Look into getting your ecu tuned, it can absolutely be fixed by modifying the factory calibrations.

BTW, two questions... First of all which bike/year are you talking about? And have you tried riding in B mode? It's not as good as a properly tuned engine can be, but it is fairly soft as far as throttle response.
 

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2016 .. It has a power commander and I ridden in A, B ' &Standard mode .. I just took another round the block. It's seems it's not the motor but in the trans or chain . hard to pin point . feels kinda jerky. WOT it's a beast or At least it is to me .
 

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A chain with excessive slack can cause lash. Clean, lube and adjust your chain; see what that gets you.
 

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this is a product of the stock ecu mapping. To fix this you need to turn off the o2 sensor which you can not do with the pcv

The o2 sensor is active at light throttle and lower rpm. The o2 sensors job is to make sure the bike passes EPA inspection. To pass the sniff test the bike must be too lean for proper throttle response. So while it is active the response on the throttle is soft and weak and off throttle it falls on it face.

When you roll on the throttle the o2 sensor is initially on so the bike is soft. You roll on a little more and the o2 sensor shuts off and now you have proper power. You roll off and the o2 sensor turns on and the bike falls on it face.

if you cruise around 25-30 mph in second gear on most of these bikes you can find the spot where the o2 sensor is turning off and on. The bike will actually surge. It speeds up as it turns off and slows down as it turns on

My $200 flash will fix all of this

 

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I just wanted to know if anybody had the issue with your bike when just cruising down the street. My bike seems to want to pull or coast. There really isn't no in between. This happens when cruising low speeds in residential areas.
From the title of your post and what you said in your first comments I'm taking it NOT as a surging problem but a power control issue? Poor throttle control of an engine with good power and torque can do exactly what you're describing. It's making so much power that it's either accelerating or decelerating, no steady cruise power. This is mostly in the throttle mapping, but can also be helped with mixture and ignition timing tuning. In other words, it's fixable. You either fix it by giving the throttle more resolution/fine control in just off idle conditions or you soften the off idle power itself. I prefer to give the throttle mapping more control over low areas and then exponential opening past half throttle so no overall range is lost.

Sometimes you actually have to change the throttle hardware itself, like Throttle Tamer does. It can also be done right at the cam on the throttle body itself. On Yamaha marine engines I've machined replacement throttle cams with finer control off idle but then ramp up the movement past half throttle. The main cause of all of this sensitive off idle throttle response of these bikes is the fact it's opening 3 throttle bodies at once. It's hard to get fine initial opening control when you're opening throttle bodies that also need to be big enough for 12k rpm flow.

So can you please clarify if you're talking about a surge or a situation where the power delivery is either on or off? Those are two VERY different things.
 

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Adjust the throttle cable so there is almost zero slack/play in it.
 

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The main cause of all of this sensitive off idle throttle response of these bikes is the fact it's opening 3 throttle bodies at once. It's hard to get fine initial opening control when you're opening throttle bodies that also need to be big enough for 12k rpm flow.
I don't agree that the number of throttle bodies has anything to do with it. Early KTM V Twins had notoriously vicious off idle twitchiness. And most 4 cyl bikes are more progressive off idle.
The problem here, as Vcyclenut said is the factory maps being optimised for emmisions, on an engine that makes a lot of low and mid range torque for it's capacity.
 

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I'd comment on the last two posts but until the OP comes back and clarifies what his issue is, discussing this further is pointless.

Throwing uneducated guesses and cures for shortness of breath when the patient actually has a broken leg is pointless.
 

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I'd comment on the last two posts but until the OP comes back and clarifies what his issue is, discussing this further is pointless.

Throwing uneducated guesses and cures for shortness of breath when the patient actually has a broken leg is pointless.

i was the one that brought up surging but that is not what i was saying is the problem he is describing, i was just showing him a way that he can actually feel the o2 sensor turn on and off. Which is what i believe is causing the on/off throttle he is describing. I receive multiple phone calls/ emails a week about the same thing on stock mt/fz09. Its one of the main reasons people get the ecu flash.

I do not think my opinion is an uneducated guess, I thought it was very clear what he was describing especially when it is a very common complaint. but hey what do I know
 

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I can confirm that Vcyclenut’s ECU flash fixed this problem . I had it flashed back in 2016 and haven’t looked back . As long as I’m smooth with the throttle this doesn’t happen anymore
 

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I'd comment on the last two posts but until the OP comes back and clarifies what his issue is, discussing this further is pointless.

Throwing uneducated guesses and cures for shortness of breath when the patient actually has a broken leg is pointless.
If you are going to start posting disparaging comments you are not going to be very popular around here. You have no idea about my level of mechanical/technical knowledge, and Vcyclenut is a long term member on here with a great deal of knowledge that he has hard earned and is willing to help with free advice.
For your info, I have ridden nearly all the Triumph triples, they do not have the twitchiness of early 09's. I believe MV's are smooth too. They have 3 TB's.
Later model KTM's were also improved.

It'd pay to tone it down.
 
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If you are going to start posting disparaging comments you are not going to be very popular around here. You have no idea about my level of mechanical/technical knowledge, and Vcyclenut is a long term member on here with a great deal of knowledge that he has hard earned and is willing to help with free advice.
For your info, I have ridden nearly all the Triumph triples, they do not have the twitchiness of early 09's. I believe MV's are smooth too. They have 3 TB's.
Later model KTM's were also improved.

It'd pay to tone it down.
 

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If you are going to start posting disparaging comments you are not going to be very popular around here. You have no idea about my level of mechanical/technical knowledge, and Vcyclenut is a long term member on here with a great deal of knowledge that he has hard earned and is willing to help with free advice.
For your info, I have ridden nearly all the Triumph triples, they do not have the twitchiness of early 09's. I believe MV's are smooth too. They have 3 TB's.
Later model KTM's were also improved.

It'd pay to tone it down.

Nor do you know mine sir.

When I mentioned the throttle bodies, I was talking on the level of Fluid Dynamics, exposed surface area between plate and bore, plate angles, throttle body bore diameters and even bore shaping, intake velocities and vacuum levels, and of course fundamental engine design characteristics.

Just one of those factors, bore shaping, can fix these kinds of issues. In this particular application, that's simply a cost item. In other words, it would cost Yamaha too much to source or spec a throttle body without a straight bore before and after the plate. Radiused bores around the throttle plate greatly improve smoothness and control of the initial airflow through the bore as the plate is opened.

You talked on the level of "I rode a bike once and it felt like this so you're wrong". lol.

Oh and "being very popular" has NEVER been a goal of mine. At almost 5k posts on a forum with almost no traffic, I'm guessing it's important to you. I'll stay out of your sandbox, sorry.
 

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Congratulations. The first ever on my ignore list.

It didn't take long for your true colours to show.

Bye
 

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Wow that escalated quickly....
To the OP - I'll 2nd the advice to tighten up your throttle cable - I think getting the throttle cable snug made as much difference as the flash for me personally. More time riding helps to - you'll learn to be extra smooth at the transition point.
 

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Wow that escalated quickly....
Yep. We don't need newbies coming here and bagging guys like Vcyclenut in their first few posts. He knows more about 09's and probably many other bikes than Mr GM will ever know.
 
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Further to adjusting the throttle cable. If the OP doesn't already know, make sure the TB's are fully closing on full lock - both sides. Open the throttle about half way and let it return on it's own. You should hear a click as they close.
 

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Oh and "being very popular" has NEVER been a goal of mine. At almost 5k posts on a forum with almost no traffic, I'm guessing it's important to you. I'll stay out of your sandbox, sorry.

Problem solved!
 

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2016 .. It has a power commander and I ridden in A, B ' &Standard mode .. I just took another round the block. It's seems it's not the motor but in the trans or chain . hard to pin point . feels kinda jerky. WOT it's a beast or At least it is to me .
All other B.S. put to the side. Call a local Yamaha dealer and have them run your V.I.N. See if there is a ecu update recall. Free to you and may solve all your issues, Assuming it needs to be done.
 
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