Bazzaz and stock o2 connected

[DukeMaster]

Hello, since we are all aware how closed and open loop function couldnt we just leave the stock o2 sensor connected and not disabled. I mean, closed loop will still be controled by engine cpu for maximum efficiency and open loop will be altered by bazzaz zfi. From my understanding we can ajdust closed loop because we disable the o2 sensor. For example, if we install decat exhaust and k&n filter without piggyback the bike will run lean only in open loop, not colsed loop. Then we just need to alter fuel in open loop for those changes. This seems like a best option for fuel economy and altitude changes etc.

Also, does anyone know when closed loop ends and open loop starts, rpm and % throtle figures?

Thanks

 

[mattv]

Hi DukeMaster,

There's some similar discussion here: https://www.rc390-forum.com/forum/electronics/2725-2017-fuel-management.html

Chad mentioned closed loop is about <%60 throttle.

It seems to me that the bike runs lean in closed loop even in the stock configuration. I experience lean surge at low speeds and rpm. I think opening up the intake and exhaust without addressing that would make it worse.

That said, this is the first fuel injected bike I've owned***, so don't take my word for it!


***I have an '85 BMW K100RS that's fuel injected, but the fuel injection is controlled by an analogue circuit, not so much an ECU, and it "just works" under just about any condition/modification.

 

[DukeMaster]

I have run the bike with catless akrapovic and no bazzaz and the surge at the low rpm was totaly eliminated. The only thing I was able to determine that the bike wont pull nicely at 7k+rpm on full throtle. From my understanding, it needs less fuel when there is a cat, but once you remove it the cpu will adjust the fuel, it wont adjust it for the open loop (higher rpms and higher throtle openings) because in the open loop o2 sensor input is ignored and the fuel is read directly from the map stored in cpu. Thats being said, and since I am not racing the bike it is viable to think that I dont need to use the closed loop ajdusting. I will try it and see how it handles with bazzaz and o2 connected.

If anyone has anymore input I would really appreciate it.

Thanks

 

[DukeMaster]

UPDATE:

I have disconnected bazzaz o2 eliminator and connected stock o2 sensor. Then I adjusted the map that has no fuel corrections below 60% throtle and 7.5k rpm (which corresponds to closed loop).

Here is what I have concluded:
1. Popping was reduced by great amount, almost no popping except here and there.
2. It does seem a little bit leaner and the performance has been slightly affected.
3. It gets greater mpg.

Mods that I have on my bike:
Akrapovic without cat and db killer
K&N filter
Bazzaz ZFI

Now I am going to test it with with map that has adjustments for closed loop. I will just disconnect o2 eliminator and connect stock o2 sensor.