Poor mileage equals problem?

[baobei]

I have owned a 2015 FJ-09 for 3.5 years.  It has 9,533 miles on it.

My average mileage over this time is 34mpg.  More recently I've been getting 26-32mpg.

I've been jealous of other owners who get great mileage.  For example, the Fuelly chart shows mileage anywhere between 32mpg and 56mpg, with the average being around 44mpg.

http://www.fuelly.com/motorcycle/yamaha/fj-09/2015

I keep the bike in B mode most of the time.  I goose it from time-to-time but I'm not super crazy on it.  Most of my miles are in-town.  The bike is stock except for an ECU flash in 2017 (EDR Performance).  The average mileage before flash was 38mpg and after was 33mpg.

Just wondering if this poor milage is a symptom of something wrong with the bike.  For example, does this indicate that I need to syncronize my throttle bodies?  Or is this completely normal?

I've replace the spark plugs and air filter recently as well.  Didn't change mileage.

[betoney]

In almost 3 years of ownership, I have ridden close to 45,000 miles on my '15 FJ.  I reset my average fuel reading with each and every fill-up, I average around 43-47mpg.  I have a buddy who also owns a '15 FJ and he gets very similar mileage to a tank.  Your results of 26-32mpg while riding in B mode and seldom riding hard does indeed sound like something isn't quite right.

I know that the manual says to replace the spark plugs at 8k but that is ultra conservative, even changing them at 23-25k mine have always looked and performed good on all previous bikes.  I know several riders who double my interval.

In the 3+ years of ownership, how has the bike performed?  how is throttle response?  how did the plugs look when you changed them, dry and mocha brown or wet and black?

[baobei]

The bike seems to run well.  I've had it serviced at a couple of shops and no mechanic has ever commented on how it runs.

The bike is wicked quick.  It often intermittently drops out on hard acceleration as the front wheel comes off the ground and the traction control drops it again.

The mechanic who changed the plugs said I had too much carbon on them and I should frequently keep the bike over 6k RPM to "blow it out" in the future.

[norcal616]

Getting ECU reflash will drop MPG a few points in general or more depending on variables

I personally dunno who EDR performance is/quality of said tune so that is unknown to me at what they aim for in terms of tuning...

Is the airbox breather hose kinked( you won't hear the "whine" noise from airbox if hose is kinked) , are you still running the stock exhaust- if so is the O2 sensor reading correctly...

[baobei]

I don't recall a "whine" noise, so that might be something!  Where could I look on bike to check this?

Still on stock exhaust.  How would you go about determining if O2 sensor is reading correctly?

This is what the flash covered, they said:

• • 1 to 1 throttle
  • Ignition
  • Engine braking
  • Injector shutoff
  • Idle
  • Fan activation
  • Fuel mapping

[Buggy Nate]

2 hours ago, baobei said:

The bike seems to run well.  I've had it serviced at a couple of shops and no mechanic has ever commented on how it runs.

The bike is wicked quick.  It often intermittently drops out on hard acceleration as the front wheel comes off the ground and the traction control drops it again.

The mechanic who changed the plugs said I had too much carbon on them and I should frequently keep the bike over 6k RPM to "blow it out" in the future.

Any mechanic that says things like that is hopeless IMO. If a bike is tuned correctly it won’t load up the plugs with carbon. I’d be getting the tune checked.

[skipperT]

52 minutes ago, baobei said:

I don't recall a "whine" noise, so that might be something!  Where could I look on bike to check this?

Still on stock exhaust.  How would you go about determining if O2 sensor is reading correctly?

This is what the flash covered, they said:

• • 1 to 1 throttle
  • Ignition
  • Engine braking
  • Injector shutoff
  • Idle
  • Fan activation
  • Fuel mapping

Did you tell them you had a stock exhaust?

i wonder if perhaps they flashed your ECM with a tune meant for an aftermarket exhaust. It would explain the poor fuel mileage and carboned-up plugs. 
 

You need a scope to accurately test an o2 sensor. Do you smell “rotten eggs” ever while riding? If so, that also indicate that your catalytic converter is dealing with a too-rich condition, esp at part throttle / cruising speeds. 
 

I’d contact EDR performance and speak with someone... it will be difficult for them to completely analyze the issue without the bike in front of them, but any reputable tuner should be open To discussing your fuel mileage concerns and satisfying (you) the customer. 
 

-Skip

[norcal616]

55 minutes ago, baobei said:

I don't recall a "whine" noise, so that might be something!  Where could I look on bike to check this?

You might be able to see it if you look from the sides along the top of motor, but you just may have to pull the airbox up to see, maybe get a friend to see/help... The hose is on bottom of airbox and goes to valve cover... The "whine" is distinct, you will notice if you did have a kinked hose vs a non kinked hose( I should mention I removed the noise damping foam under the gas tank) so that might make the "whine" more audible... 

I had a kinked airbox hose and didn't even notice it till I blew a seal on the clutch arm at the engine cover...after fixing the seal and unkinking the hose, I definitely noticed the distinct "whine"...

[1moreroad]

There was a former forum member (Lawrence of Arabia or something like that) who ran through entire tanks at B mode and noticed a drop in mileage compared to STD. 

How recent? About a month ago ALL of my vehicles' mileage dropped about 15%. At this time last year the same thing happened. Different gas stations, different brands. I'm assuming it was the switch to winter blend gas  

[skipperT]

1 hour ago, 1moreroad said:

There was a former forum member (Lawrence of Arabia or something like that) who ran through entire tanks at B mode and noticed a drop in mileage compared to STD. 

How recent? About a month ago ALL of my vehicles' mileage dropped about 15%. At this time last year the same thing happened. Different gas stations, different brands. I'm assuming it was the switch to winter blend gas  

Good point! I forgot that there’s a definitive mileage drop when winter blend fuel starts being sold. 
-S

[baobei]

15 hours ago, skipperT said:

Did you tell them you had a stock exhaust?

i wonder if perhaps they flashed your ECM with a tune meant for an aftermarket exhaust. It would explain the poor fuel mileage and carboned-up plugs. 
 

You need a scope to accurately test an o2 sensor. Do you smell “rotten eggs” ever while riding? If so, that also indicate that your catalytic converter is dealing with a too-rich condition, esp at part throttle / cruising speeds. 

The had the bike for the ECU flash, so I'm sure they knew about the stock exhaust.

No, can't say I've smelled rotten eggs.

[baobei]

6 hours ago, 1moreroad said:

There was a former forum member (Lawrence of Arabia or something like that) who ran through entire tanks at B mode and noticed a drop in mileage compared to STD. 

How recent? About a month ago ALL of my vehicles' mileage dropped about 15%. At this time last year the same thing happened. Different gas stations, different brands. I'm assuming it was the switch to winter blend gas  

I was confused.  I run in standard mode all the time, not B mode.

Here's the spreadsheet with my mileage history:

FJ-09 Mileage Tracker - Google Sheets

---

Sheet1 Odometer,Gallons,Miles,Mileage,Avg,Notes 3285,34.86,Avg...

 

[1moreroad]

Can't pull up a chart but looking at the numbers there is no pattern. You had a tank at 15 mpg followed by a tank at 50 mpg. That's weird and suggests an environmental problem not a bike problem. Do you always fuel up at the same station or is there a pattern where you fuel up? Maybe bad gas at a particular pump. How long does the bike sit between rides? There's no dates on your chart. 

Sort of half kidding, half not, you should do several multi-tank steady throttle rides (touring not SPORT touring) and see if the mileage settles down to a regular number. 1000 miles in a long weekend could be informative. 

[Cruizin]

You want to be damn picky when choosing tuner. Our resident tuner @2wheeldynoworks has to fix alot of "other shops" tunes. Anyone can get the software and start making tunes, that's kinda scary. 

[2and3cylinders]

On 11/5/2019 at 7:24 AM, 1moreroad said:

There was a former forum member (Lawrence of Arabia or something like that) who ran through entire tanks at B mode and noticed a drop in mileage compared to STD. 

How recent? About a month ago ALL of my vehicles' mileage dropped about 15%. At this time last year the same thing happened. Different gas stations, different brands. I'm assuming it was the switch to winter blend gas  

I only run B in the rain, and even then rarely.

+1 on a winter gas potentially causing a mileage drop.  I've never got the +45 mpg many others have.  E10 kills mileage too, as we only have E10 available unless I'm up in certain Cheeseheadland counties.  With a light -to- moderate right wrist I was recently managing 43 or so mpg with my OEM size DB screen (but with adjustable spoiler on top) but it dropped to <39 (albeit with a heavy-handed throttle input) with my cold weather Givi Tour barn door screen and spoiler.  I'll have to check TB sync, which I can do easily because I plumbed vacuum lines extending from the TB ports to the left side that have capped 3/16" hose connectors.  But over the last 35k miles, I'd say I've averaged maybe about 40 mpg or so.

But with that low of mileage, Baobei, there is something wrong!