I have a 91 cbr f2 with 33,000 miles on it.... Im only getting about 39 mpg this season compared to what last season was like 60. I;ve lost some power got some backfire at cruising sometimes... I kno the carbs are clean,synced the coils have all tested good, full battery voltage... it is due for a valve adjustment... but im not sure if thats everything.. didnt know if i would lost that much mileage... other thing i was wondering is it possible for it to be the timing chain or anything... just want some pointers before i take the beast apart(finally due)

I think your calculations from last year are off. I get about 39mpg outa my 07. That's about average for a 600cc. I could be wrong but I have never heard of a 60 mpg average on anything but a hybrid car.

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2007 CBR 600RR Two bros. C/F slip on--Dynojet usb P/C--Custom mapped--Vortex sprocket -1 front+2 rear--DID X-ring chain--hh pads --Pilot power rubber--competition werkes F/E. Oem blue solo seat cowl and no rear bitch pegs!(no offense to any bitches meant)

I agree with Drew!! My 98 F3 with 38ooo miles gets about 38-40 mpg even with a -1+2 sprocket combination. At stock gearing best I could get was 44 MPG!!! Needing a valve adjustment wont affect gas mileage that bad. But I think you may have been figuring you MPH wrong last summer!

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1998 CBR F3 R.I.P.
2004 zx6r R.I.P.

my buddies yamaha gets 62. i have a 4 gallon tank and 130-140miles is pushing it while before i could get 220 before i filled it. I am due for a valve adjustment but didnt if anything else was wrong cuz i dont have much power anymore either.

Yamaha what, scooter??? No offense but there isnt a sportbike, or motorcycle for that matter, that gets 60mpg!! Sorry but it just isnt happening. I get about 150ish miles from a tank of gas, which is about 4 gallons, and that hasnt changed since the bike was new!!!!

Are you SURE you got 220 MILES from a tank???

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1998 CBR F3 R.I.P.
2004 zx6r R.I.P.

I past this post up a few times, but just stopped to read, NO way on that 62 or 60. My bike gets like 110 to the tank when beating on her. around 140-160 babying

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Because chicks love the beads
2001 CBR 600

Exactly!!!!

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1998 CBR F3 R.I.P.
2004 zx6r R.I.P.

are you sure you speedo wasn't set on kilometers???? I say this because 140 MILES converts to 225.3 kilometers!!!

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2007 CBR 600RR Two bros. C/F slip on--Dynojet usb P/C--Custom mapped--Vortex sprocket -1 front+2 rear--DID X-ring chain--hh pads --Pilot power rubber--competition werkes F/E. Oem blue solo seat cowl and no rear bitch pegs!(no offense to any bitches meant)

ah ha Drew figured it out!!!! Great job bro.


BTW IM IN LOVE with you avatar!!!

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1998 CBR F3 R.I.P.
2004 zx6r R.I.P.

Smart ass.

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Because chicks love the beads
2001 CBR 600