Fuel Economy Mystery

[nofreeride]

I have always gotten right around 42mpg on my Gen1. For the last half dozen tankfuls, I have gotten almost exactly 50mpg per the FJR tripmeter.

Things that changed:

1. Removed the top box (Pelican Style)

2. Added the V-stream with four (two on each side) 5/16 nuts for spacers

3. New front PR2 (old front was Avon, rear is PR2)

All riding conditions, including commuting, freeway, and back roads (all one up).

Did not change:

1. Riding style

2. Fueling procedure

3. No other mechanical tweaks or maintenance done

What are your thoughts? Could those add up to a 15% increase? Which one primarily?

 

[GalaxyBlue]

That V-Stream really makes the FJR a brick trying to slice through the wind. I gain about 3-4 mpg when i run my stock-cut-in-half summer windshield.

Edit: I guess i should have read this closer. You have a GAIN with those mods. I can get 42 on a good day! Usually 38... I better just let the pro's answer this!

 

[SkooterG]

Removing box will have a small effect. Windscreen may too, depending on size of your old one and the position you run. Tire no effect. These will not add up to 15% however.

Have the ambient temps been high? That will have a small effect imho.

My guess is your riding style has been slightly different for whatever reason (mood, traffic, ect....). That will have the biggest effect (other than altitude).

 

[CAJW]

I'm with Skoot on this one. Riding style (i.e. how much the right wrist is exercised) makes a huge difference. Recently on a 2 week trip, I averaged 45, but got a high of 53.8 and a low of 33.5 so wind, speed etc. can add up to big swings in mileage.

 

[nofreeride]

Removing box will have a small effect. Windscreen may too, depending on size of your old one and the position you run. Tire no effect. These will not add up to 15% however.
Have the ambient temps been high? That will have a small effect imho.

My guess is your riding style has been slightly different for whatever reason (mood, traffic, ect....). That will have the biggest effect (other than altitude).

Temps have been cooler than normal for this time of year, if anything. I went for a ride with my Dad and my uncle, Honda Shadow and GoldWing, so yes I wouldn't be surprised if my fuel economy went way up during that. But it's been several tanks since then and I'm back to my regular routine, still almost 50mpg. ??

 

[dcarver]

Change in fuel formulation? Different brand? The flux capacitor finally fluxed?

 

[Geezer]

The only thing I can think of that would have that much affect id altitude. The higher I ride the better mileage I get. Since that doesn't appear to be a factor for you, are you buying the same fuel as before?

 

[nofreeride]

Change in fuel formulation? Different brand? The flux capacitor finally fluxed?

Yeah, had to stop at Shell a couple times (I don't know why, but my Dad ingrained in me since I was young that Shell was crappy gas). Maybe it had something in there that finally cleaned out my injectors. ??

 

[SkooterG]

Maybe your math sucks.

:lol:

 

[Joel Rappoport]

For the first 20K I averaged 43 mpg. Mix of ride-to-work and road miles. During the IB5000 my average on the second leg was 48 mpg, close to 3K including interstates at the posted speed limit, mountains and city riding. Bike now has 25K.

 

[08FJR4ME]

I have also noticed a 2 to 3 mile increase in mileage as fo late. I have been thinking they switched the formulation to winter fuel. I haven't change a thing on the bike.

Dave

 

[Greb]

I stretched a tank out to 305 miles and 60.7 mpg on a recent trip up to Montana, but I rode through yellowstone with my dad on his Harley so that explains the requirement to nurse the throttle. I left him in the dust without even trying.

 

[08FJR4ME]

Although fun, I can't say that it is an acomplishment. Kinda like shootin fish in a barrel.

 

[bikerkash]

Suggestion, put the top box back on and the other windshield and see what happens. Also do an actual MPG check, not relying on the bikes computer, and see what that says.

 

[Checkswrecks]

How about the tripmeter being 8% off (up to 4 mpg), since it's related to the speedo, I can get a 1-2 mpg change with the VStream up or down, and a little math or measurement error?

 

[highcountry]

I consistently get 44-45 mpg with mixed riding conditions. I have a Vstream, otherwise stock.

 

[flyball]

A 15% increase is huge and I don't think anything you mention would equate to that. I would check out your odometer/tripmeter and do an actual check of fuel used over known distances. Something is screwy and it will be interesting to see if you figure out why you have such a big difference.

 

[jim oneill]

My 08 is basically stock and I get 47 to 48 mpg all the time

 

[NMRoadRunner]

I always get around 50.5mpg, running pretty hard, but I ride at 5500' + above sea level all the time. Less air means less fuel!