So I had an extra Big Gun ECO exhaust for my Polaris 850 Sportsman, and I decided to fit it to the Z800.

[2015 Z Force 800 53/Trail EPS]

Nice work. Did it improve performance?

I won't be able to test until Monday. But I'm sure after the fuel management re-calibration, it will. I suspect moving the AFR to about 13.2:1 I should see a considerable performance change.

I suspect moving the AFR to about 13.2:1 I should see a considerable performance change.

Are you increasing or decreasing the stock AFR?

The stoiciometric ideal for gasoline is 14.7:1. Meaning the cleanest burn mixture that does create excess pollution. The first number (14.7) is the air, the next number (1) is the fuel. 14.7:1 AFR rarely offers the best power output.
So running a 13.2:1 AFR would be less air to a given amount of fuel (richer and more power). Now that does not mean I'm reducing the air volume to the motor. Instead I'm increasing the fuel due to the improved volumetric efficiency the new exhaust is creating to the combustion chamber. This can get complex in its explanation.
I feel like I just gave you an over complicated explanation, but there you go.

I feel like I just gave you an over complicated explanation, but there you go.

Not at all, I'm familiar with OL & CL systems & how they work. CFMOTO system is much more automotive style than any of the other brands. Using a narrow band O2 for CL operation & a catalytic converter. I'm guessing other parts of the world have tighter emissions than North America for off road vehicles.

I didn't ask my question the way I wanted to. I'm assuming the CFMOTO fuel injection system will go OL when certain parameters are met so the ECU will use a mapped fuel delivery. I'm curious what AFR they are mapped for when in power enrichment mode, if it is 14.7 as you stated it won't make power & it's hard on engine parts.

I've a fuel box & WB, just did not have time this season to play around. Even have the fancy muffler that came with Stage II performance kit I took off......because of the dismal performance.

So if you had a chance to play around, what was the AFR WOT & did you change it......good or bad results?

This system seems to respond exactly the way the modern Harley fuel system works. Open loop until full operating temp is reached and then closed loop takes over. Unlike a Harley, I am having trouble determining what load demand is reactivating the open loop. The AFR meter is not showing the traditional blip of enrichment when open loop is reactivating. I know for sure, the stock map is way to lean on the decel enleanment (15.8:1).  Next time I'm out, I will hook up the laptop and see if I can record the map as I run it through the paces. As for impressions of the slip-on, I think it was worth the trouble of fitting it to the machine. If all goes well, I will run it on the dyno and refine the map. Then I will post the final results of AFR throughout the range.

What software do you have to data log with? I can real time with the PDA that comes from CFMOTO, no data log.

I will see if I can find out the parameters for power enrichment.

It would be best just to get it on the dyno & get some of this shit figured out  I won't have time or access until the spring.

I use a K&L Supply brand interface module using their supplied software for Delphi injection. I found the switching point for open loop. It looks like %60 throttle position