6th Gen Average Fuel Mileage

Got out today with a couple buddies. Filled up at our meeting point and again at 186.9 mi (3.972 gal.) That worked out to be 47.5+ mpg. Spirited pace! Lots of time in VTEC! High 80's to mid 90's air temp! Another 6th gen on the ride had like mileage! He's not a forum member though.

 

Hey lift... your mileage has always been nice and high.

Are you running a PCIII?

 

No PCIII, Bone stock save the K&N and Staintunes. This bike used to be VARollOn's. I bought it through the forum classifieds. I'd like to try a PCIII as my 5th gen with a lot more tweaks got mid to high 40 mpg as well.

 

I know alot about cars, but am a relative newcomer to the motorcycle world, so forgive me if my comments appear a bit ignorant or naive.

There were several comments questioning whether it was the VTEC that was the cause of mileage that was less than expected. I've owned 2 Honda VTEC cars, and I can tell you this: when kept out of VTEC, they are very efficient. My 1998 Accord had a 3.0 liter V6 VTEC, and I would regularly get 32 mpg with it on the highway. For a 3600 pound car, that is amazing.

So I started to wonder if it's simply a matter of gearing? The Interceptor is a sport bike after all, and while I don't know the specific gear ratios, I would venture a guess that it's geared toward the sporting end of things, which would not help mileage.

Here is a formula I've used in the past that might help shed some light on this:

Vehicle Speed = (0.00595) * ((RPM * r)/(R1 * R2))
RPM = (Vehicle Speed * (R1 * R2)) / ((0.00595) * r)

0.00595 = (60 minutes per hour) / (1 mile = 5280 feet = 63,360 inches)
r = Tire radius (in)
RPM = Engine speed
R1 = Transmission gear ratio
R2 = Rear axle ratio

I've only used this for cars, but the concepts are all the same so with a little adjustment for bikes, I thought it might be useful. So my question here is, would a lower (numerically) rear axle (sprocket) ratio help matters here? Thoughts? Comments?

 

All that math is pretty impressive but there is one big catch to the gearing theory. Final drive gearing on a motorcycle is not constant or consistant. Depending on what type of riding and what types of roads the radius of the rear tire changes effectively changing the final drive ratio. Simply put the more time you spend at a given lean angle changes the radius of your tire. So if you ride the slab most of the time your final drive ratio would remain more constant. If you're a twisty junkie and spend alot of time off of the center of the tire the final drive ratio would average differently due to the smaller diameter of the rear tire used in 5280 ft. The torque factor put to the ground at a given load and lean angle changes as well think about that.

I still say that most of someone's fuel mileage with the VFR is controlled by how smooth they are with the throttle both rolling on and off and with how effective they are with using the power available as in gear selection and/or smoothness of up and down shifting in a given situation.

 

45-48mpg back and forth to work 37 miles one way...over half way through city trafic...other half open road.

 

Excellent points. As I stated, the formula is intended for cars, and needs a little tweaking to be adapted for bikes, particularly non-shaft driven ones. It also does not take into account the lean factor you mentioned. I have found the formula to be very accurate for cars, but take it with a grain of salt for bikes - for commuting, it should be fairly accurate. For the twistys...well, we're not really caring about mileage at this point are we? :biggrin:

 

Agreed! As this post is pointing out there are no absolutes, but many many shades of gray. Everybody rides differently! Everybody rides for different purposes! Different regions of the country are forced to buy and use different blends of fuel! All of these are factors in the fuel economy of the VFR! One thing we all agree on is that the VFR is a capable machine.

 

My mileage seems to be aceptable. I don't commute on any of my bikes so I guess the lion's share of my riding is in the twistys.

 

4100 miles Salem OR ---- Mt Rushmore SD

Keep in mind as you read these numbers that I had a double stack tank bag (stuffed) and all 3 Givi cases on the back. But, with that said the low tank was 37 mpg (all hwy, some up and down, heavy wind, speeds at or around 85mph). The high tank was 49 mpg (hwy, speeds at and around 70 mph). Very happy with the numbes.

 

Latest MPG

Last tankful:

46.58 MPG!!!

Dave

 

I filled up today....i got 203 miles on 4.6 gallons and that avgs out to just over 44 mpg

 

and I'm driving like a cage - slow, reliable, boring, and wondering what my MPG will be when I'm done. Unlike before, I'm not passing people at twice their speed, or cruising at twice the highway limit
-turgut

 

I have a longer trip planned near the end of July... Planning on training the right wrist to be smooooth.

 

It would be interesting to group the readings by model year - I was looking enviously at 5.0lizard's figures then realised his/her profile says 2003. Lifttruck (equally impressive MPG) is riding an 04, but those with worse readings (myself, alterego, neverlost...I haven't checked them all) are they on 2007 models? RVFR seems to be riding a pre-vtec too?

Maybe we should qualify the readings, OK there will be some variations because of riding style (e.g. wheelie-bound VFR-guy2000) but is there an underlying trend towards worse MPG on the later bikes?


My consistent 42mpg is on a 2007 model

 

OK - VFR 2008 model.. Stock everything. tires slightly low (1-2 psi lower than recomm),
mainly 20 mile rides to work and back, and some weekend. DOCILE riding with MPG in mind
I found out, that I did 16.45 km per liter of 95 octane unleaded.
Which converts to: 38.69 MPG

Sigh.. still low!
-turgut

 

Just curious, but what does fuel cost in Turkey these days? I am paying $4.67 per galloon for 87 octane here in CA. The bike runs fine on it so do not see any need to put higher octane at higher prices in it.
Happy riding.
Viker1

 

right now it's like 3,30 Liras, per liter..
So, if I'm correct that comes to 10 dollars per gallon!!
(gasp!)
I can't find anything lower than 95 here..

Gas is the major source of government taxes here, so that's why it's so expensive.. -t

 

47.6 mpg today, 280 mile trip.

 

I usually get about 34mpg. I commute around 15 miles each way to and from work. Heavy traffic over the bridge and freeway (13 miles). My average speed is probably only 35mph. I get about 155 miles on 4.5 gallons of fuel (when the light starts blinking). On longer freeway trips on the weekend that range goes up to about 190 miles of freeway and back road sorties which pushes my gas mileage to about 41.5mpg. Must... travel... more!!! ANCE7: