FJR Computer swap for Seq EFI?

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My suspicions are verified by Ignacio moving my question to the useless section of the forum even though his and other answers did not meet the question asked.
Now you're guilty of failing to read the Forum Terms and Rules, because if you had, you would have:

  1. known that NERPT is far from "useless"; rather, the acronym is "Never Ending Recurring Pointless Threads".. do you see the word "useless" in there? No, you do not. You see the word "pointless", because the subjects almost never, ever reach consensus, so that's where the "pointless" comes into play. But they are far from "useless", particularly to new owners such as yourself.
     
  2. Known that the answers that you seek reside in "The Best of NERPT", where approx 2/3's down this page is an ENTIRE SECTION on Fuel... including fuel mileage, octane use, etc, etc


But, here.... since it is several days from Dogpile Friday, allow me to offer some sage advice that you are, of course, free to cheerfully ignore... 'cuz Friday's not *that* far off..... :D

- If there is one person I (myself) would listen to when it comes to the FJR powerplant, it would be ionbeam. You don't know this because you are a relative newcomer. Fair enough. Now you've been informed. If Alan tells you something about fuel injection on our bikes, he is not bullshitting you. At all. His post #10 in this thread is spot-on-the-money.

- You need to simply give up on the idea that you are going to find a replacement computer for the FJR (any model year) to convert the fuel injection to sequential fuel injection. They don't exist for this model. Okay? Go ahead and ask away regarding O2 readings, etc, or.... you can read what these figures are in the "The Best of NERPT" thread mentioned above (it is buried in there somewhere). But as ionbeam correctly observed, this concept has been discussed 1001 times in the past 9 years, that's why it is NERPTy.

- The fact of the matter is..... SkooterG ears are scary-large. ************ looks like a lanky Dumbo, in fact. Think I'm kidding? Check him out standing in the center of White Pine Fever "2KDay" Finishers below..... look at those massive, huge-*** ears! :eek:

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Warchild and ionbeam (and others) are saying that my fuel numbers are off from the average. If that is so then the oxygen sensor is still a potential issue. If it is providing false readings to the computer which while false are still within spec, the fuel economy would be off and a code might not be thrown. I do not have a vacuum leak. I do not have a fuel leak and I do not smell fuel in the exhaust and the engine starts 1st time, every time so no injector leaking. The Mass Airflow sensor could be bad. The throttle position sensor could be bad. Problem is I don't feel, hear, see or smell any effect on the engine or performance. There are no codes. The bike went through its 12,000 mile scheduled maintenance at the dealer and no mention of a problem. Unless a sensor is providing false readings which are within spec the gas mileage at 35mpg is the gas mileage.

David

Warchild - The pigpile is on as my "Reputation" has dropped to -6. That would be 2 lower than when ionbeam seemed to have closed off the conversation a few responses back.

 
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Warchild and ionbeam (and others) are saying that my fuel numbers are off from the average. If that is so then the oxygen sensor is still a potential issue. If it is providing false readings to the computer which while false are still within spec, the fuel economy would be off and a code might not be thrown.
Here's my take (FWIW -- I'm far from an expert...): the O2 sensor has only the capacity to improve your economy -- not make it worse. The fuel injectors are operated via a "look-up table" in the ECU and controlled by, more-or-less, fixed parameters (temperatures, altitude, throttle opening, RPM, etc.). The Lambda (O2) sensor cuts the fuel during a few specific situations -- steady-throttle operation over a period of time, being one (when the rider is least likely to notice any driveability issues).

I do not have a vacuum leak. I do not have a fuel leak and I do not smell fuel in the exhaust and the engine starts 1st time, every time so no injector leaking. The Mass Airflow sensor could be bad. The throttle position sensor could be bad. Problem is I don't feel, hear, see or smell any effect on the engine or performance. There are no codes. The bike went through its 12,000 mile scheduled maintenance at the dealer and no mention of a problem. Unless a sensor is providing false readings which are within spec the gas mileage at 35mpg is the gas mileage.
Most, if not all, of the parameters that determine fuel consumption can be checked and verified -- with the help of an FSM.

Although I don't check my fuel economy absolutely 'strictly', I do pay attention to it at fill-ups -- miles on the trip meter, gallons used -- and it's mostly been close-to 50 MPG.

(My dad used to look at the Buick's gas guage and guess about how far he went on 1/4 or 1/2 a tank -- no paper or pencil used...)

"Annecdotal Fact": I filled the FJR at mile-post 450 (Raton) on I-25 and got off at mile-post 150 (Socorro) 4 hours later, non-stop, -- 300 miles/6 gal. = 50 MPG, 300 miles/4 hours = 75 MPH.

(very steady throttle...)

 
Getting mid-30's for city riding is simply not that far off from the norm, truth be told. Some people get more or less, depending on their throttle discipline (and about a gazillion other factors)

Warchild - The pigpile is on as my "Reputation" has dropped to -6.
No, the dogpile hasn't even lifted off yet, believe me.

Though now that you mention it, we oughta create "The best of Dogpile Fridays" thread like we did for NERPT... that would be a hoot! :lol:

 
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Just looked through the owners manual. The number 87 shows up on page 6-33 ("EAU03087") and 8-5 ("Volume, Capacity" "X 0.8799"). That is all. I do not see any section which lists the octane requirements for the fuel.

 
Just looked through the owners manual. The number 87 shows up on page 6-33 ("EAU03087") and 8-5 ("Volume, Capacity" "X 0.8799"). That is all. I do not see any section which lists the octane requirements for the fuel.
Try searching for "octane" instead...my manual says this:

Your Yamaha engine has been designed to use regular unleaded gasoline with a pump octane number [(R+M)/2] of 86 or higher, or a research octane number of 91 or higher.
 
charismaticmegafauna - The ECU has a certain range in which the oxygen sensor is expected to function. High readings for lean, low for rich (or vice versa - Not sure what the range is for the FJR). If the fuel system is providing fuel at a normal rate and combustion is producing the standard 14.7:1 ratio (ideally 14.7:1, but almost always lower to prevent knocks and plug detonation) the sensor should provide a reading which corresponds. If the sensor is bad it may still provide readings which are within the expected value but are not accurate to the actual air:fuel ratio. It may produce a reading which tells the computer the ratio is lean and the computer will add fuel to offset this. If the ratio was where it is supposed to be and the system adds fuel to offset a lean claim by the sensor it will become rich instead. This is how an oxygen sensor can make your fuel economy worse.

David

 
charismaticmegafauna - The ECU has a certain range in which the oxygen sensor is expected to function. High readings for lean, low for rich (or vice versa - Not sure what the range is for the FJR). If the fuel system is providing fuel at a normal rate and combustion is producing the standard 14.7:1 ratio (ideally 14.7:1, but almost always lower to prevent knocks and plug detonation) the sensor should provide a reading which corresponds. If the sensor is bad it may still provide readings which are within the expected value but are not accurate to the actual air:fuel ratio. It may produce a reading which tells the computer the ratio is lean and the computer will add fuel to offset this. If the ratio was where it is supposed to be and the system adds fuel to offset a lean claim by the sensor it will become rich instead. This is how an oxygen sensor can make your fuel economy worse. David
Okay -- you know much more than I (sorry I got involved...)

Good luck w/y'r problem

 
Warchild - Removed.

Phroennips - The only 86 is on page 8,5 under the Torque section of the conversion factors ("86.794" and "0.8679").

Nothing under "Fuel" for octane. Nothing under "Octane" for Octane. Nothing under "91". I am excluding unrealted returns in this line of reply.

David

 
charismaticmegafauna - I'm not ripping you, I just have a background in Computer Science and an in depth understanding of automotive/motorcycle repair. I do hope my response provided you with some insight. What I wrote to you is the reason you are sometimes told that you need a sensor when you go to a repair shop even if your check engine light isn't on. Not all codes trigger the light in all vehicles and not all shops wait until a code is displayed to check the readings from sensors.

David

 
...The ECU has a certain range in which the oxygen sensor is expected to function. High readings for lean, low for rich (or vice versa - Not sure what the range is for the FJR)...If the sensor is bad it may still provide readings which are within the expected value but are not accurate to the actual air:fuel ratio
David, I addressed the O2 sensor back in post #10, right after you brought it up. The way the FJR fuel mapping is set up the O2 sensor is primarily for emissions and not for mileage. Read the post, then disregard it or dispute it.

...Phroennips - The only 86 is on page 8,5 under the Torque section of the conversion factors ("86.794" and "0.8679").
I previously suggested you read the OWNERS MANUAL where on page 3-10 it says to use 86 octane or higher if the engine knocks. The service manual is about service and repair, not general user information.

 
I don't doubt that I can use 87 as the compression ratio is only 10.8:1. Dealers are often full of it which is why I tend to do the majority of work myself. I bought the bike from the previous owner with whom I went to the dealer to pick the bike up. I don't doubt I can use 87.

The difference between 87 and 93 is 93 contains more cyclic octane (aromatic octane - octane in a ring form). Both contain straight chain octane (octane in which the carbons are in a straight line). Straight chain octane does not stand up to compression as well as cyclic octane does. This is because in the ring form the carbon atoms are bonded on two sides providing greater strength and less flexibility in the molecule, especially under compression. In the straight chain only the center 6 carbons are bonded on two sides by adjoining carbon atoms allowing twisting and easy malformation of the molecule. That allows straight chain octane to fall apart into smaller molecules under compression. This means that unless you have a high compression engine you do not need a greater proportion of cyclic octane. That does not mean the fuel will not work as well in a low compression engine, it simply means the engine will not run any better (without knocking, pinging or detonation) with higher octane. It will not get lower gas milage by using higher octane but a high compression engine will get lower fuel economy by using lower octane fuel (because of the breaking of of the molecules of straight chain octane).

The compression of the FJR is low enough that 87 is should not be a concern unless it has variable valve timing. I thought it might as the dealer claimed "91 or better." The dealer may have been thinking of an R1 which has very high compression and does need higher octane.

David

 
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Paranoia is costly.

$230 buys what, 10 tanks plus?

Get out on the highway and stay under 75mph for a whole tank and see how that goes, bet you end up in the high forties.

Franz: Yeah. Listen to me now, and believe me later ;)

 
ionbeam - I agree that an oxygen sensor plays an important role in emissions and it does so by monitoring fuel burning efficiency. If it reports a lean ratio the change in resistance or current will signal the ecu to increase fuel volume. If it reports a rich ratio it will signal a decrease in fuel volume. In doing so it prevents unburned hydrocarbons from being needlessly dumped through the exhaust and emitted into the atmosphere (emissions). If fuel is being sent through the exhaust because the sensor is reporting a lean situation even if the ratio is not lean (a bad sensor) both the emissions and the fuel usage will increase.

We are both correct.

David

Edit: changed Right to Correct

 
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Zorlac - We are back to the leg thing: The footpeg position is such that I don't dare travel over the speed limit on this bike. If I am focused on my legs I cannot focus on the road and could easily wind up with a case of Dead at high speed. The speed limit here is 65 and 65 I go.

Wait a minute... I live in western Massachusetts. You know what that means? Mountains and hills.

I am not worried about a few dollars. I can always make more money.

David

 
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I'd like to get 45mpg from this thing! I get 35mpg from my car, I rather my motorcycle hit a higher mark.
Sorry, I don't know of anyone providing aftermarket ECU.

I will add that sub-45 mpg city cycle isn't off what others report. I do a fair amount of city driving during weekday commute and only average mid-30's (riding the heftier GenII). Funny, but loaded up for long trips, cruising 75+ and I average 50mpg. My interpretation has always been she's a big bike with a big motor and takes a bit of fuel to get her going from the stop lights.

Since the engine runs well from idle to redline, I've never suspected O2 or other issues. I know most car ECUs are sophisticated enough to detect and report faulty O2 and other sensors. The FJR will report some system faults, but whether a marginal O2 is included, dunno. Wish Yamaha was a little more open with that info.

 
- The fact of the matter is..... SkooterG ears are scary-large. ************ looks like a lanky Dumbo, in fact. Think I'm kidding? Check him out standing in the center of White Pine Fever "2KDay" Finishers below..... look at those massive, huge-*** ears! :eek:

wpf249.jpg
So THAT explains his nickname.....

NORAD!

 
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