Juice Box and O2 observations

[RShrimp]

I have been having problems with a flat spot around 4000 RPM at normal (closed loop) operation.
When the bike is cold it runs great and at full throttle it runs great but during normal cruise it is terrible.

I just added an EVO O2 eliminator and it has solved the issue!

Observations:
The bike runs a fixed map when cold and at full throttle.
The Juice box simply modifies the injector pulse length (makes it longer)
Illastrative Example of What happens (my theroy)
With the O2 sensor in place:
Computor says, pulse = 10ms
Juice box says, Make it 12ms
O2 sensor says, Help me I am rich
Computor says, pulse = 8ms
Juice box says, make it 10ms
O2 sensor says, I am happy now

So, while the Juice box is trying it's best to richen things up the computor is doing it's best to keep it lean (this only happens during closed loop)
At full throttle the juice box works and it works when the bike is not up to temp.

With the O2 eliminator in place:
Computor says, pulse = 10ms
Juice box says, Make it 12ms
O2 sensor says, I am happy now and am always happy.

My point is that I dont think the Juice box can work as intended unless you get rid of the O2 sensor.

My bike now runs great and pulls good from 1500rpm
Before, anything below 5000 was a challange.
I do not run it that slow but the point is, you can now if your just puttin'
Very happy with this mod.:2thumbs:
I have exhaust and intake mods as well

[Magic Man]

Glad your Spyder is running better for you, but that is not how it works.

The JB also grabs and changes the O2 signal to the computer.

Remember the lead you have to hook to the O2 sensor from the JB?

The flat 0.5 volt signal now coming from the O2 with your O2 eliminator in essence makes the Spyder run in the "back up fuel map's fixed mode." This fuel map is set to protect the motor against "burn down from being too lean" so it is a "rich program" meaning your AF ratio is now rich all the time.

Normally your "check engine light" comes on when this happens so the EPA allows this "rich operation" as it is assumed you will be bringing in the unit for service and not be running it around very long in this "too rich" condition.

One of the main things the O2 eliminator does is "trick" the ECM into not turning on the check engine light that would usually happen under conditions like this.

The the low RPM lean flat spot you had is in most Spyders stock or otherwise. Any mods make it show more and become worse. I had been working with Two bros about opening up the low RPM window (mode #1)on the orginal JB to allow us to adjust that out, but the work on the new JB Pro began, so that project was put off.

However, the new JB Pro and PC units will finally let you adjust out this problem once they are ready for sale.

MM

[Firefly]

Full throttle when the engine is still cold? Not good to do.

It is my understanding that the Spyder runs on rich settings during warm-up, which may explain why you find it was running better cold. I also added the O2 mod back into things and it really helped those flat spots--- but I still have that nasty(and potentially very dangerous) engine cutoff when going from WOT back to cruising--- like after passing someone.:yikes:

[Lamonster]

sig

[Eddie]

The 02 mod helped mine a lot. Still not perfect but' much better. :2thumbs:

[Campverdefela]

:agree:Seems to be the best combo of mods short of major engine work or the 5K turbo. Its cost me a total of 1K, its been worth it.
The 02 mod helped mine a lot. Still not perfect but' much better. :2thumbs:

[RShrimp]

Glad your Spyder is running better for you, but that is not how it works.

The JB also grabs and changes the O2 signal to the computer.

Remember the lead you have to hook to the O2 sensor from the JB?

The flat 0.5 volt signal now coming from the O2 with your O2 eliminator in essence makes the Spyder run in the "back up fuel map's fixed mode." This fuel map is set to protect the motor against "burn down from being too lean" so it is a "rich program" meaning your AF ratio is now rich all the time.

Normally your "check engine light" comes on when this happens so the EPA allows this "rich operation" as it is assumed you will be bringing in the unit for service and not be running it around very long in this "too rich" condition.

One of the main things the O2 eliminator does is "trick" the ECM into not turning on the check engine light that would usually happen under conditions like this.

The the low RPM lean flat spot you had is in most Spyders stock or otherwise. Any mods make it show more and become worse. I had been working with Two bros about opening up the low RPM window (mode #1)on the orginal JB to allow us to adjust that out, but the work on the new JB Pro began, so that project was put off.

However, the new JB Pro and PC units will finally let you adjust out this problem once they are ready for sale.

MM

Thanks for clarifying that. Thats why I called "My Theroy" Good to get the facts!
Bottom line is it works!