Cobra FI2000 O2 Settings

I have installed a Cobra tuner in my 09 Deluxe. I put it in after my Accel self tuner went south. Also have S&S slip on tapers with a K&N filter. The one that lets you keep the stock cover after installing their backing plate. The bike runs smoother and with more power as promised. But I have lost about 7 miles per gallon. Has anyone out there had the same results. If so how did you tweak the factory settings for better milage. Stock settings are 3.5 G, 2.5 Y, 4 R. The manual suggests leaving the G as it comes. But this is the cruise setting. So is it best to start there.

Thanks for the reply Cowboy. I considered the fun factor being the problem. So I did a 60 mile easy run to do a test. Thats where I got the 38 mpg number.