We would really need to know how the bike is running. Is it running hot? Then it is too lean. Exhaust popping on decel? Too lean. Black exhaust and gas smell? Running rich. Fouled plugs? Running rich. Either way will effect performance and mileage. Usually with a new exhaust you will be running on the lean side of the spectrum. If you are giving it a lot of gas frequently then your mpg will drop just like any vehical but you should still be getting in the +40's to lower 50's for mpg. I have posted this before on other threads for fine tuning the FI2000r and here it is again. Last time I will post it though as we do have a search.
**********THAT'S WHY THE FI CONTROLLER IS ADJUSTABLE**********
You will have to tune it for your bike. Someone elses settings are likely not right for your bike. The suggested settings from the manufacturer give you a good STARTING POINT to get you in the ballpark. I know, Cobra does not have a 'tuning guide' in their instructions, so you're kind of on your own, but other manufacturers publish these and they are available on the web. I typed up some tuning guidelines a while back, They are
somplace in the "C-90 Folder", I'll look later if I get time. As an example:
Turtle Joe and I have nearly identical bikes with all the same components. The FI controllers we use are made by Dobeck... same as a FI 2000/Techlusion... My settings are (think of a clock face) 9:00, 4:15, 6:45.
Joe's settings are 7:00, 2:45, 6:15. If you ride the bikes they run the same. If I set Joe's controller like mine the bike would run terrible and get poor gas mileage too. When I tune FI-2000/techlusion/Lloydz/Dobeck 2nd generation controllers I start from scratch. I pay no attention to the 'numbers' of where the pots are set. I tune the bike 'til it runs right and the settings are where they are. One might be 4, 5, 4 and one might be 5, 5, 5 and where the pots are pointing isn't what to tune by, is it?
You have to ride it to tune it. You can't tune the motorcycle without a load on it. Don't worry about the lights/colors/settings. TUNE IT.
left pot is idle/cruise/light throttle accelleration (less than 1/4 throttle).
middle pot in midrange accelleration. Right pot is wide open throttle above like 3800 RPM. Engine must be fully wamed up for 8 minutes first. Turn all pots all the way down (couterclockwise). Try to hold a steady 30-35 MPH in 3rd gear. The bike will buck and surge like a %%%%%. Increase the left pot (clockwise) in 1/2 hour increments on a clock face until it gets better.
Now do 15 minute changes until it will cruise steady at light throttle and on/off the throttle isn't abrupt. Now, increase the setting 15 minutes more and STOP. Set the third/right-hand pot equal to the 1st/left-hand pot for now. Hold a steady 35 MPH in 3rd gear for a couple of seconds then nail the throttle open and count 3 seconds. Repeat this a few times while increasing the middle pot in 15 minute increments until acceleration gets better... then it will get worse... when it gets worse, back up 15 minutes and stop there.
Get a Sharpie marker. Mark the speedometer at 40 MPH, 70 MPH and 90 MPH.
Find a deserted road where you are safe and won't get a ticket.
Run the bike at wide open thru the first 3 gears, shifting at the marks on the speedo to avoid the rev limiter. Adjust the 3rd/right-hand pot open 1 hour and try that.... go back where it was, then closed 1 hour and try that... one will be better... that's the way you want to go. Put it back where it was originally and adjust for best acceleration and quickest pull to the shift points. TIP: If the throttle is wide open and the bike is pulling... slowly let off
the throttle... if the bike accelerates better off-wide-open it's most likely too rich. This will get you really close. Fine tune in barely decernable turns to find the sweet spot on the idle/cruise pot for best drivability. Make ONE tiny change at a time... ride it a while... don't pass judgement right away.
You may also need a little tweak one way or the other on the middle pot... for best roll-on pull. After you ride it a while, you'll get a better feel for finding the sweet spot on that one too. Again, make ONE tiny change at a time... ride it a while... don't pass judgement right away. The bike will tell you what it needs... you just have to apply your knowledge of what pot
effects what, while listening to what the bike is saying.
