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sudden loss of mileage

jagarra

Gerard
Went for a ride yesterday, covered the same route that I had about 3-4 weeks prior, distance was approximately 160 miles between gas stops. Route covered mountain twisties, highway 395, couple of construction zones and a 60 mile stretch with little traffic and high speed. Filled up and it took 4 gallons which is about 40 mpg, previous time 3 weeks ago took a hair under 3 gallons so over 50 mpg previously.:scratch

I have the AFX module still set at 7 pulses, air cleaner is nice and clean, I replaced injectors with the new R1200 style from Germany a few K ago. Only difference was the ambient temperature, it was hot in August, high 90s, now in the 70s.
 
First thought is the previous ride you didn't fill it all the way, and this ride you filled it to the top. What's your "usual" mileage?

Second thought is a fuel leak. Do you smell gas when you turn the key or when it's running? Pull the fairing and examine the fuel hoses, especially at any connections, screw clamps or quick disconnects.
 
I have had several such episodes with my 2003 single-spark R1150R. It is very fussy about fuel quality. In every case that I can recall things got better the next tank of gas, and then even a little better than that on the second refill.
 
I was thinking I didn't fill up properly either. I do have the metal quick disconnects, no apparent gas leak or smell. Got gas at the same place on both fill ups of each ride, Costco and Standard Oil, I try to use stations that don't have all those rubber fume catchers on them. Maybe they had the winter blend in the tanks, that usually causes the mileage to go into the toilet.
Will do another ride just to see, :) may as well take advantage to the cooler weather with less bugs.
 
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