Why is the fuel mileage not better???

[dart1963]

just an FYI... I remember reading an article a while back... motorcycles in general get crappy gas mileage.... it's by pure luck we get 40something mpg, but if you look at weight/hp vs. a car, we should be getting something like 200mpg (can't remember the exact figure, but it was something nuts like that)....

the reason we don't do better is aerodynamics... in the article, it said there were early attempts to make the bikes more aerodynamic... but they essentially looked like a wing on it's side, and acted like one in a turn (whole bike lift off at almost any lean). If anyone else members this article and can link it, it was interesting.

Obviously what everyone else has said is a factor as well, just adding a bit more info.

 

[lberhold]

FZ6R Mileage

I agree that the FZ6R gets poor mileage. My last bike was a gsx-r 600, and I was always getting about 47-48 mpg. Now on my FZ6R I am getting 43-45 mpg. Not too different, but it is still less distance per gallon, and less power as well. I rode my gsx-r much harder than I ride my FZ6R. In addition, my brother had an R6 last season, and he was getting 44-46 mpg, still a minor improvement compared to the FZ6R, and yet again more power. We are talking a difference of around 30 hp, and still no mpg improvement.
My only conclusion is that the engine is designed less efficiently. I can also guarantee that a motorcycle is not less aerodynamic than a car. There is less surface area F = (1/2)p(v)^2(C)A. It is physically impossible to have greater drag with significantly less surface area, and not much difference in drag coefficient.

 

[Scott_Thomas]

Another post from the sands of time. :zombie:
J/K, still better than starting a thread for the same thing which will end up being merged anyway. I get about 48mpg with mixed riding. Haven't had my PCV/Viper exhaust setup on long to know what kind of mileage I'll get.

 

[06330i]

I WAS, getting around 46 mpg when I was stock. Now with the addition of an air filter, full exhaust, and jb pro I lost about 10 mpg or so. Also gotta take into consideration that when you put add on's to the bike you're more tempted to ride it harder (like I do)

 

[Scott_Thomas]

I agree that the FZ6R gets poor mileage. My last bike was a gsx-r 600, and I was always getting about 47-48 mpg. Now on my FZ6R I am getting 43-45 mpg. Not too different, but it is still less distance per gallon, and less power as well. I rode my gsx-r much harder than I ride my FZ6R. In addition, my brother had an R6 last season, and he was getting 44-46 mpg, still a minor improvement compared to the FZ6R, and yet again more power. We are talking a difference of around 30 hp, and still no mpg improvement.
My only conclusion is that the engine is designed less efficiently. I can also guarantee that a motorcycle is not less aerodynamic than a car. There is less surface area F = (1/2)p(v)^2(C)A. It is physically impossible to have greater drag with significantly less surface area, and not much difference in drag coefficient.

Your also lugging more weight. The stock wet weight is around 467. The r6 is probably 50 lbs lighter. Check Perdurable's weight loss thread. My girl is down at least 15 pounds, maybe a lil more.

Sent from my SGH-I777 using Tapatalk 2

 

[MistahT]

I WAS, getting around 46 mpg when I was stock. Now with the addition of an air filter, full exhaust, and jb pro I lost about 10 mpg or so.

I only had the stock exhaust for 2 full tanks of gas, but I was in the high 40s, almost 50 with it. With Viper and Marthy's map I'm usually low 40s, sometimes high 30s if I've been doing too many WOTs from red lights.

 

[nismos14]

I WAS, getting around 46 mpg when I was stock. Now with the addition of an air filter, full exhaust, and jb pro I lost about 10 mpg or so. Also gotta take into consideration that when you put add on's to the bike you're more tempted to ride it harder (like I do)

Weird, I have all those mods and still get 45-48mpg.

 

[BKP]

Averaging about 48mpg. I don't have any mods that would effect engine performance.

This is actually *up* from about 43-45, when it was new (almost 9k on it now).

I ride it hard -- never babied it. 50/50 around town/longer rides. All synth since ~1200 miles.

YMMV (literally).

 

[Scott_Thomas]

Weird, I have all those mods and still get 45-48mpg.

Are you using jbp or pcv? Jbp with sport map would affect mileage. PCV with adv gear map has touring map for 4,5 and 6 gears.

Sent from my SGH-I777 using Tapatalk 2

 

[rhnatyk]

I drive it like an old man (which I am) and rarely exceed 7000 rpm. I never use WOT and routinely short shift. Result: 50-55 mpg. As everyone else has mentioned, fuel economy is largely a factor of how you drive it.

 

[alaskanflyboy]

I agree that the FZ6R gets poor mileage. My last bike was a gsx-r 600, and I was always getting about 47-48 mpg. Now on my FZ6R I am getting 43-45 mpg. Not too different, but it is still less distance per gallon, and less power as well. I rode my gsx-r much harder than I ride my FZ6R. In addition, my brother had an R6 last season, and he was getting 44-46 mpg, still a minor improvement compared to the FZ6R, and yet again more power. We are talking a difference of around 30 hp, and still no mpg improvement.
My only conclusion is that the engine is designed less efficiently. I can also guarantee that a motorcycle is not less aerodynamic than a car. There is less surface area F = (1/2)p(v)^2(C)A. It is physically impossible to have greater drag with significantly less surface area, and not much difference in drag coefficient.

Most of this is coming from an aeronautics perspective, but it applies to our bikes as well. Drag is influenced by a lot more than just surface area. There are three main types of drag, only one of which affects our bike: Parasite Drag (the other are Induced Drag, produced by lift pulling backwards; and High Speed Drag, produced by the shock wave at Mach speeds). Under Parasite Drag we have five sub-types, which I'll use the definitions from Flight Theory for Pilots 4th Ed.:

1. Skin Friction Drag is caused by the viscous friction within the boundary layer. The total area of the aircraft skin that is exposed to the airstream will be affected by this type of drag. Skin smoothness also greatly affects this drag. Flush head rivets. waxed and polished surfaces, and removal of aluminum oxide help reduce skin friction drag.
2. Form Drag is the type of parasite drag that is influenced by the shape or form of the aircraft. Streamlining the fuselage, engine nacelles, pods, and external stores helps reduce form drag.
3. Interference Drag is caused by the interference of the boundary layers from different parts of the airplane. If the drag of two component parts of an airplane are measured individually and then the parts are assembled, the drag of the assembly will be greater than the drag of the parts. The boundary layer interference is the reason for this. Smooth fairings at surface junctions reduce this type of drag.
4. Leakage Drag is caused by differential pressure inside and outside the aircraft. Air flowing from a higher pressure inside the the fuselage through a crack or door seal will create an airstream that impinges on the airflow around the aircraft and creates drag. Door and window sills are sealed with masking tape before starting an air race to lessen this drag.
5. Profile Drag is of particular interest to helicopter pilots. Profile drag is the drag of the moving rotors, and it develops anytime the rotors are in motion. So this drag can exist even if the aircraft is not in motion or developing lift.

All of these types of drag affect our bikes (and cars) in some form. Leakage drag is almost nil since there isn't much place for higher pressure air to reside inside the bike's fairings. I'd say Profile Drag is the second least concern since the only place we have rotating parts moving faster into the relative wind than another part is our wheels, but our wheels are definitely more exposed than most cars.


Skin Friction Drag is the one you mentioned is less than a car's, of course. However, for the same area on the skin of our bikes we also have screws and other fasteners that stick out making each square foot that less efficient than a car's. You also have the rider whose gear or clothing is rarely a smooth surface, adding to this drag. Leather is still grainy and porous at the microscopic level, and synthetics? Well, we can easily see that isn't not a smooth surface without the microscope.


I expect Interference Drag is the greatest factor on a bike than on a car. We have most of our engine, all its screws and sharp junctions exposed to trap air and disrupt smooth airflow around us. We also have our bodies out there which create junctures with the bike that definitely disrupt smooth airflow. All of this is typically hidden within the body of a car. We also have a radiator that is exposed heavily to the wind. While it's great for cooling efficiency, it crates a lot of drag on its own.



Drag is really a lot more complex than just how much surface area is exposed; it's also what kind of surface is exposed, the angles at which is is exposed, and anything that disrupts the smooth shape. Bikes just have a less overall aerodynamic shape than most cars by the way they're designed, mostly because bikes with everything covered inside just don't appeal to the majority of riders.

 

[Anthony]

hmmmmmmmmm, I'll have to put some thought into this one.

 

[MichaelInVenice]

There's another thing, and that is that even when ridden less aggressively, bikes seriously outperform cars.

A bike that was powered to match a Honda Civic's performance and top speed, and driven in an identical manner would probably be a 250 or less, running entirely on the lean side of the curve. It could probably be made to hit a number close to 100 in normal mixed driving. By "normal" I mean "the way a normal Civic driver would drive."

But that's not the expectation of even small motorcycles, and we pay a penalty.

 

[pandyman]

So what did you guys get during run in?

My bike is an '13 model , and restricted throttle so no WOT riding and i'm only getting about 200kms per tank of 17L .. it seems very poor mileage comapared to my old VTR250 honda?

does this improve after run in ? is it set to run rich for the first 1600kms?

 

[Bert-Aus]

My commuting riding will generally get to about 230km a tank before the F-Trip begins and then can squeeze another 50kms out of it.

But if I only commute on a tank it consists of about 20 trips (2 weeks) where the bike sits for about 2-3mins warming up before I get on and ride...

Going on hills rides I can do around 200kms and the fuel gauage only dims 2 bars.

Last years Phillip Is ride I managed to get 320km out of the tank to then only able to refill with 15L.

Overall I have noticed from my 2 1/2 years that the more you sit the revs around 5-8k the better mileage you get
...like others have said before depends on your riding,

 

[pandyman]

Thanks Bert

I thought the lower rpms may have been causing it to labour a bit , my commute to work is pretty slow speeds so a lot of 3-5thousand rpm 60km/h type riding.
Sound like i need to stick to a lower gear and keep the revs in the happier range

 

[Bert-Aus]

... my commute to work is pretty slow speeds so a lot of 3-5thousand rpm 60km/h type riding.
Sound like i need to stick to a lower gear and keep the revs in the happier range

My commute is the same deal, which means I'm lucky to get out of 2nd...
but there is always the LONG way home

 

[yellowfz]

Most of this is coming from an aeronautics perspective, but it applies to our bikes as well. Drag is influenced by a lot more than just surface area. There are three main types of drag, only one of which affects our bike: Parasite Drag (the other are Induced Drag, produced by lift pulling backwards; and High Speed Drag, produced by the shock wave at Mach speeds). Under Parasite Drag we have five sub-types, which I'll use the definitions from Flight Theory for Pilots 4th Ed.:

1. Skin Friction Drag is caused by the viscous friction within the boundary layer. The total area of the aircraft skin that is exposed to the airstream will be affected by this type of drag. Skin smoothness also greatly affects this drag. Flush head rivets. waxed and polished surfaces, and removal of aluminum oxide help reduce skin friction drag.
2. Form Drag is the type of parasite drag that is influenced by the shape or form of the aircraft. Streamlining the fuselage, engine nacelles, pods, and external stores helps reduce form drag.
3. Interference Drag is caused by the interference of the boundary layers from different parts of the airplane. If the drag of two component parts of an airplane are measured individually and then the parts are assembled, the drag of the assembly will be greater than the drag of the parts. The boundary layer interference is the reason for this. Smooth fairings at surface junctions reduce this type of drag.
4. Leakage Drag is caused by differential pressure inside and outside the aircraft. Air flowing from a higher pressure inside the the fuselage through a crack or door seal will create an airstream that impinges on the airflow around the aircraft and creates drag. Door and window sills are sealed with masking tape before starting an air race to lessen this drag.
5. Profile Drag is of particular interest to helicopter pilots. Profile drag is the drag of the moving rotors, and it develops anytime the rotors are in motion. So this drag can exist even if the aircraft is not in motion or developing lift.

All of these types of drag affect our bikes (and cars) in some form. Leakage drag is almost nil since there isn't much place for higher pressure air to reside inside the bike's fairings. I'd say Profile Drag is the second least concern since the only place we have rotating parts moving faster into the relative wind than another part is our wheels, but our wheels are definitely more exposed than most cars.


Skin Friction Drag is the one you mentioned is less than a car's, of course. However, for the same area on the skin of our bikes we also have screws and other fasteners that stick out making each square foot that less efficient than a car's. You also have the rider whose gear or clothing is rarely a smooth surface, adding to this drag. Leather is still grainy and porous at the microscopic level, and synthetics? Well, we can easily see that isn't not a smooth surface without the microscope.


I expect Interference Drag is the greatest factor on a bike than on a car. We have most of our engine, all its screws and sharp junctions exposed to trap air and disrupt smooth airflow around us. We also have our bodies out there which create junctures with the bike that definitely disrupt smooth airflow. All of this is typically hidden within the body of a car. We also have a radiator that is exposed heavily to the wind. While it's great for cooling efficiency, it crates a lot of drag on its own.



Drag is really a lot more complex than just how much surface area is exposed; it's also what kind of surface is exposed, the angles at which is is exposed, and anything that disrupts the smooth shape. Bikes just have a less overall aerodynamic shape than most cars by the way they're designed, mostly because bikes with everything covered inside just don't appeal to the majority of riders.

Motorcycles have a much greater hp to weight ratio than most cars, meaning motorcycles have the power to overcome those little flaws of bolts and bumps (riders).
If this was not true a Harley would never make it down the road. ROFL (sorry had to take a Harley dig)
What about if the front wheel in the air, that causes drag as well.

 

[pkoko]

any reason why the gearing on 6th gear isn't taller? I think 60 MPH at 5K is too high

 

[nismos14]

any reason why the gearing on 6th gear isn't taller? I think 60 MPH at 5K is too high

Probably because this bike gets better gas mileage at 6-7k then at 3-5k.