Ivan's ECU Flash

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How do I get the ECU out? Gen 3
Remove the battery cover and RH removable fairing panel. You can access the bottom ECU connector from the side through a square hole and the top connector from the top. From DC’s pic, there’s a plastic cover held in place with the single screw shown and two clips at the top. Up clip the top to slide the ECU out. It’s tight but doable.

Call me if you have questions John.

~G

 
When it's available for the GenII, I'll send mine off. I've always been a little skeptical about stuff like this, but George sounds happy. Might as well see what happens.

 
I'm ready now. Just waiting for the donation from G to help it along.
Taking a four day weekend and playing around in OR, ID & MT...I'll have your donation when I get back home 'junior!!
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--G

 
I'm no expert at this stuff, but why eliminate the O2 sensor? Seems the best option would be to keep the O2 sensor to keep the tuning Ivan wants adjusted on the fly for all conditions.

 
I've wondered about the same thing Skooter, seems counterintuitive to me.

Maybe one of these smart engineering types has an answer.

 
Just sent mine in. I'm off tomorrow on a 2 week road trip to UT in the truck so the ECU should be here when I get home.

Ivan turns the ECU's around in a day. Looking forward to the driveability improvements on the '13.

 
I've wondered about the same thing Skooter, seems counterintuitive to me.

If it's a narrow band sensor, it's not much use in managing a richer mixture. It only outputs rich, stoichiometric, lean.

That's why the ECU only looks at the O2 sensor at small throttle openings (closed loop mode) where emissions are critical and the engine needs to stay at stoichiometric. It's also why the PC-V Autotune swaps in a WB sensor.

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I've wondered about the same thing Skooter, seems counterintuitive to me.

If it's a narrow band sensor, it's not much use in managing a richer mixture. It only outputs rich, stoichiometric, lean.

That's why the ECU only looks at the O2 sensor at small throttle openings (closed loop mode) where emissions are critical and the engine needs to stay at stoichiometric. It's also why the PC-V Autotune swaps in a WB sensor.

An excellent response! And a swell graph! Thank you. I knew the PC-V still used the sensor, I didn't realize they changed it to a WB sensor. Perhaps Ivan's tune should do the same?

 
I'm an embedded software engineer for the last 30 years but in a different discipline so I may not know what I'm talking about here.

Even with a narrow band sensor that outputs 3 states, I don't see why it can't be used to adjust the fuel to the center. Each cylinder fires rpm/2 number of times, and by adjusting little by little in a closed loop it will always be back to center.

 
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I'm an embedded software engineer for the last 30 years but in a different discipline so I may not know what I'm talking about here.
Even with a narrow band sensor that outputs 3 states, I don't see why it can't be used to adjust the fuel to the center. Each cylinder fires rpm/2 number of times, and by adjusting little by little in a closed loop it will always be back to center.
The reason is that the bike runs better when richer than stoich, so you don't want it to center. Most tunes will richen up the AFR to get to around 13.8-14.2:1 across the rev range, so the narrow band sensor just keeps reporting "Rich".

 
An excellent response! And a swell graph! Thank you. I knew the PC-V still used the sensor, I didn't realize they changed it to a WB sensor. Perhaps Ivan's tune should do the same?
The ECU would probably not know what to do with the high voltage signal from a wideband sensor and would throw a code. Ivan's tune would (most likely) be fuel and spark maps only - the base ECU and its diagnostics wouldn't be changed.

On a different project, I played around with a Innovate Motorsports WB sensor that could output narrow band results to the ECU. I could program it so that when the actual AF ratio is 14:1, tell the ECU it's 14.7:1. By using this, you could offset the centering of the O2 sensor to any value you want and the ECU was fooled. A guy on ADVRider took it way farther than I did, his thread is here.

 
Very cool! While it was possible to make a WB sensor to output tri-state, it's not possible the other way around as the data weren't there :)

 
Ivan's philosophy is generally for a plug-and-play solution, but in cases where customers are commonly changing out parts, he'll leave the fueling to whatever PC you choose to install, and will provide maps for various combinations as needed..

 
I brought a 06 fully stock last memorial day with 6k miles. Now i never thought of the low end issue till i did a track on it.

at full lean opening the gas got a little dicey at the track.

In the top box the old owner left me a G2 and i also saw a throatle adjustment might help. i also moved the handlebar so the angle on my wrist is a bit open. Seemed to have helped alot. now when ivan is ready i might just sent the ecu in.

i will ride a bit more but the 300 mile day on the twisity i did not have one instance of the apex hard transition on gas . Maybe on the next track day take the fjr instead of the sv for a session.

 
How do I get the ECU out? Gen 3
Remove the battery cover and RH removable fairing panel. You can access the bottom ECU connector from the side through a square hole and the top connector from the top. From DC’s pic, there’s a plastic cover held in place with the single screw shown and two clips at the top. Up clip the top to slide the ECU out. It’s tight but doable.
Call me if you have questions John.

~G
So to be clear.....can ECU be finagled out without removing right side fairing. Can the screw be removed "through an access whole in fairing"? (not near bike to look, LOL)

Other questions:

How is fuel economy affected if at all.

Is engine breaking reduced by any detrimental amount.

Is the throttle snatch gone in sport mode now? How does the 3rd mode compare to the others?

Thanks for input

 
So to be clear.....can ECU be finagled out without removing right side fairing. Can the screw be removed "through an access whole in fairing"? (not near bike to look, LOL)
Other questions:

How is fuel economy affected if at all.

Is engine breaking reduced by any detrimental amount.

Is the throttle snatch gone in sport mode now? How does the 3rd mode compare to the others?

Thanks for input
ECU can most definitely come out w/o removing the RH plastic. I should add that removing the single shoulder-screw on the RH side allows more fairing flex for easier access to the ECU plugs. With a thin screwdriver you can unsnap the top of the plastic cover over the ECU. ECU slides out.

I've only burned about three tanks of fuel since the flash...too many competing priorities. I'm hedging providing a absolute mileage number as I don't have enough data points yet. I will say it *seems* my '15 is averaging ~5% better mileage than stock. By July 3rd, Nakusp and Spearfish will be in the books and I'll have ~3500 miles of fuel mileage numbers to report. Stay tuned!

Can't say there's any difference in engine braking. I typically don't use a lot of brakes and I haven't changed my riding style since the flash. With Ivan's changes, the off/on throttle transitions are much smoother than stock. I've purposely lugged the engine down in 2nd gear and the pickup is very smooth, almost electric motor smooth. Third mode is smack-dab between [now] dull Touring and over-eager Sport. Linear throttle response and you get exactly what you wanted. My new favorite mode.

I didn't have many complaints when stock, but with Ivan's flash the FJR is a better motorcycle. Smooth, eager, rev-happy...it reminds me of a puppy bouncing around your feet - full of energy and ready to go!

~G

 
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