Extremely low MPG

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@RossKean , I am curious - I am contemplating on decommissioning my PCIII on my '06, and getting Ivan's flash. Have you ridden a Gen II with the flash completed, or have you had others report that the abrupt throttle issue is solved by the flash?
 
Thanks @RossKean for the quick reply and for the very informative link. I feel more confident now going forward with getting the flash done.
 
I havent really looked in it really well when it got to the point of blinking. Just a glance. Ill keep an eye out next time I fill up and check the mileage. Im taking it easy on the bike so its kind of disheartening if it is.

Thanks for replying
Ride it like you stole it. Really, wind that bike up to 8K rpm every chance you get,the motor likes it and may just clear out all those carbon deposits. Then check your milege the old fashion way and report back your findings.
 
Original poster mentioned staying in second and third (gear) a lot; well, you're not going to get stellar mileage that way. All other suggestions valid.
 
I know another that changed throttle tube on 2007 + Put a commander on... commander makes his bike run poorly. But he has so many bikes, he does not ride it much, it could be the gas getting old. I luv my 2009, it's linear , and goes w/o hesitation. All the add on boxes do is make it rich...yes rich = quick torque but inefficiency sometimes . If you want rich power ... simply screw all the sync screws in CW a 1/4 turn. Starting with OEM #3 TB settings Now your reducing air at idle and magically the bike pulls off the line better. But it will be rich all the time below 3000...how much rich is a question?
 
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Riding hard, but making sure I'm in top gear when not accelerating out of a corner (as in straight-road open country-type stuff), I am seeing about 38 mpg out of my bone stock 2008. (Way better than my 98 SuperHawk at 28 mpg....needing a gas station by 100 miles...)
 
I ran 800+ miles = 4 tanks of fuel . Did not reset the fuel avg. by the end of this it was showing 44.5 . Yes i like 4th and 5th gears because 90% I ride past 3000rpm in all gears on back roads and highway…. as we should. Hell , the bike pulls hard once past 3000 in any gear. I ain’t farting around .
If you aren’t seeing 4th and 5th. Then this whole discussion was a joke. …cheers,
 
Did not reset the fuel avg. by the end of this it was showing 44.5
The fuel average consumption is based from last reset only up to a point, call it xxx miles (maybe 300 or so). After that, it gives you a running average for the last xxx miles.
 
Legacy loses the first bar (of 16)
Ooops. Don't know what I was thinking when I typed that. The temp gauge has more bars, and the fuel gauge has smaller bars too, but there's still only 8 of 'em.

I wonder if the sender can be adjusted to give a more usable rate?
 
Ooops. Don't know what I was thinking when I typed that. The temp gauge has more bars, and the fuel gauge has smaller bars too, but there's still only 8 of 'em.

I wonder if the sender can be adjusted to give a more usable rate?
i was recently wondering the same thing as I have a very pessimistic fuel gauge. if the float assembly is on a bar, that bar may be bent to correct the error. this would probably require some trial and error to get it just right.
 
i was recently wondering the same thing as I have a very pessimistic fuel gauge. if the float assembly is on a bar, that bar may be bent to correct the error. this would probably require some trial and error to get it just right.
People have done it but I wouldn't unless something was very wrong. i.e. Tank never shows full or you are out of gas when the gauge says you still have some. I am between 5 and 6 litres (closer to 6) remaining when I go to count up mode. As long as I know what it is and it is reasonably consistent, I'm OK with that. It is important to know how far you can ride when the gauge starts flashing.
 
... hitting 2 bars=2 gallons... 1 flashing= ~ easy 1.25 gal. or so. Depends on how well you fill up to be sure of this remaining amount for the future rides.
 
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I seem to recall some dyno runs on the Gen1 in the early days that suggested Yamaha's fuel map was tuned to give maximum mileage at around 3,500 to 4,000 rpm -- highway cruising speed territory. I don't know if that continued through the later models before they started providing selectable maps.
 
Out of curiosity, I waited until the last bar started flashing and then topped off at the closest pump (1.5km away). 19 litres almost exactly, so 6L of reserve. Pandora was about 5L of reserve.

So I think the primary difference is the float height and may tinker with that in the future.
 
...

I wonder if the sender can be adjusted to give a more usable rate?
I had a serious look at doing something useful electronically to improve the gauge particularly at low levels, I gave up because the sender bottoms out with quite a lot of fuel left. I doubt bending the float wire would help much, the variable resistor was not at its limit when the float stopped moving.

Wrote it up here. The work was done on my 2010, it would read across certainly to any FJR 2006 or later, don't know about earlier.
 
Wrote it up here. The work was done on my 2010, it would read across certainly to any FJR 2006 or later, don't know about earlier.
I just had a quick look -- interesting research for sure. I'll read it in depth later. I already suspected any modification would have to be physical, for just the reason you mention: the elevator doesn't go down to the basement level, as it were. That would require a longer arm or different sender.

I'm not looking to meter the reserve capacity. I'd be happy if the gauge was reasonably linear across the top 20 litres. And I think a slight bend to the arm would get this one (06) closer to the accuracy of my 03.

But ultimately, I grew up on bikes without either fuel gauge or trip meter. I can adapt and live with this ;-)
 
I just had a quick look -- interesting research for sure. I'll read it in depth later. I already suspected any modification would have to be physical, for just the reason you mention: the elevator doesn't go down to the basement level, as it were. That would require a longer arm or different sender.

I'm not looking to meter the reserve capacity. I'd be happy if the gauge was reasonably linear across the top 20 litres. And I think a slight bend to the arm would get this one (06) closer to the accuracy of my 03.

But ultimately, I grew up on bikes without either fuel gauge or trip meter. I can adapt and live with this ;-)

I had been riding for 19 years when I finally got a bike with a fuel gauge. I'm still in the habit of zeroing the trip meter when I fill up, and I can do a better job of estimating my range than the bike does. :) The fuel gauge on mine bugged me for a while. I didn't like the idea that it reported back to me in eighths instead of letting me see that the needle is "just a tad above half." Like you, I've adapted.
 
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