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Discussion Starter · #1 ·
During my 8000+ mile rune to the rally and back I noticed my mpg dropped from about 50 to 30. I stopped at Sturgis BMW and they told me the code informed them that my O2 sensor was toast. When home, I did a major tear down and did a lot of maintenance things. I replaced the O2 sensor with one recommended on this board. It was for a 540 BMW auto ($100 vs the $367 oem one) and was the right length and had the correct plug. The issue now is, it runs great but the OBC says that I am averaging 38.3 mpg. This mpg is not pulling a trailer or running things hard at all. Does the code need to be cleared by the dealership or what is going on? At the tear down i also replaced air filter, spark plugs, fuel filter, throttle cables, installed HID lighting and general fluid change in additional to the O2 sensor.

Any ideas?
Larry
 

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Did you disconnect the battery for a lease four hours? This will do a complete reset. And remember when you re-connect the battery, do the following:
--Turn the key on.
--Open and close the throttle two full times.
--Turn off key.
Restart, ride, and see what happens.
 

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Discussion Starter · #3 ·
Well, not really. I did just return from a 10 day trip to SO CA and while gone somebody screwed with my bike and turned on the key. When I came home i found the battery completely dead and it took several days to get it charged again. I did disconnect the Neg cable for quite awhile while charging, though.
Larry
 

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lkniess said:
The issue now is, it runs great but the OBC says that I am averaging 38.3 mpg. This mpg is not pulling a trailer or running things hard at all. Any ideas?
lkniess said:
The OBC only provides theoretical mileage figures based on factors such as road speed, engine rpm's, engine vacuum, etc.The only truly reliable method of calculating mpg is dividing actual miles ridden by actual gallons consumed.
 

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2005 K1200LT
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The BC always displays a running average since the last reset. Try resetting the BC while it is in the MPG mode. It should be reading a more realistic number after you do that.
 

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DakotaDude said:
The OBC only provides theoretical mileage figures based on factors such as road speed, engine rpm's, engine vacuum, etc.The only truly reliable method of calculating mpg is dividing actual miles ridden by actual gallons consumed.
While this may be true, I've found (at least on mine) that the OBC is within a tenth or two of my math. Checked it several times. Close enough that I don't do the math anymore. I'm gonna ride it whatever it is anyway. :)
 

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Discussion Starter · #7 ·
I did a reset before my weekend ride. It was 150 miles and the mpg was about 38.
I will check the actual when I refill the tank.
Thanks
Larry
 

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Larry, you probably need a buddy to come over and give her a little spirited exercise to blow out the cobwebs! A few sustained high speed, at the redline, runs would probably get rid of that bad carbon stuff.

38 mpg is a LOT more fun than 50 mpg. IMHO

Loren
 

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Discussion Starter · #9 ·
I just took a short ride and git her filled up. the actual mpg for the last 147 mile is 42.2. I would loved to see higher!

You got someone in mind, Loren??
 

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lkniess said:
I just took a short ride and git her filled up. the actual mpg for the last 147 mile is 42.2.
Thats about what I get, spirited riding, 2 up. Now go running at 100 for a while, see it drop into the high 20's. Tires wear fast at that speed too for some reason.
 

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Naw. Just thinkin' out loud!

Loren

lkniess said:
I just took a short ride and git her filled up. the actual mpg for the last 147 mile is 42.2. I would loved to see higher!

You got someone in mind, Loren??
 
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