50cc scooter real world MPG?

[renault_megane_dci]

Basically, properly driven gear bikes should see more mpg than equivalent scooter because on a scooter you can't fiddle with the gears, someone clever did all the work for you, you paid money to start with to save yourself the hassle of thinking (and you will pay twice throught running costs (belt, fast disapearing tires and around 10% more fuel))

That being said, FI is a very good MPG boost, especially on smaller high performance engine (bikes and scooter have performance engine, they have 100cv / liter and more)

[Honda100]

I didn't run through the whole post, but I do have a wide variety of scooters and motorcycles. Also keep in mind that all of my mpg figures are very accurate as I use a measuring pitcher to add fuel to my bikes and top them off to the very brim (which you can do on a bike like a Super Cub or Metropolitan 50).

Anyway, my observations are this. Japanese fuel economy numbers are based on a cruising speed of 18 mph, which of course you just can't do. My Metropolitan (called the Crea Scoopy in Japan) is rated at 71 km per liter or 167 mpg in carb form, and 78 km/l in FI form. Now at 18 mph my Metro runs at roughly 4500 rpm and 1/4 throttle. At 30 mph it's at 7000 rpm, and at 40 (where you need to be most of the time on "normal" roads), it's at 8200 rpm and hitting the redline. So little wonder I "only" get 97 mpg. Also to note, scooters are geared for acceleration and speed, so instead of being able to take advantage of better fuel economy, you're constantly over 4-5k rpm so that you can keep up with traffic and no be run over.

Now my Super Cub 100 is geared a lot taller, and even at 40 mph it's doing a smidge under 5000 rpm. At that speed I get about 130 mpg. However, if I drop that speed to 20 mph like the Japanese ratings suggest, I am well over 250 mpg and even managed 320 on one tank. US mpg. At 20 mph and tall gears, it runs at 2200 rpm in top gear, and if you can imagine a 102cc motor at 2200 rpm, it's really nothing.

Then take my Wave 125, it has 4 speeds vs. 3 and is geared even taller so that at 20 mph it's around 1500 rpm or just above idle. Again, you can manage 200 plus mpg on it at that speed, but of course when you need to keep it at 1/2 throttle or above, you're down to 120-130 mpg again.

Anyway, I guess my point is is that cars are a lot easier to predict because they are driven in roughly the same circumstances and throttle ranges most of the time. No one can keep their foot glue to the floor for obvious reasons, so it's all 20-30% throttle most of the time, where as motorcycles and scooters need to be flogged to match speeds on road with the cars they are surrounded with. Also, remember motorcycles have the aerodynamic properties of a parachute so the faster you go, a MASSIVE decrease in fuel economy takes place.


Also, in the real world, I've found that my FI bikes (the Wave is fuel injected) isn't really that much better than the carbed ones for fuel economy. I think it's down to them being air cooled and run a tad on the rich side. Also, the fuel injected Metro (Crea Scoopy) even though it's water cooled, does noticeably worse than my carbed 02 Metro for reasons I don't understand. The 02 would do 100 plus mpg all the time whereas I am lucky to break 100 with the FI one.

[ciderbarrel]

Originally Posted by razor02097

ere is an example....

I ride my motorcycle 120 miles then fill the tank with 1.925 gallons. That works out to 62.3MPG right? I ride another 120 miles and fill the tank with 2 gallons even that is 60MPG which is a 2.3MPG difference.

I drive my car 320 miles then fill the tank with 10.925 gallons. That works out to 29.3MPG. I drive another 320 miles and fill the tank with 11 gallons even that is 29MPG which is only a .3MPG difference.

Both vehicles the second scenario took .075 gallons more however you can see since the motorcycle had less range and took less total fuel that tiny amount of fuel made a HUGE difference in fuel economy calculations!


.075 gallons is about 1.2 cups... I don't know about you but looking in a 2" filler port on a fuel tank I can't tell if I've put 1.2 cups more in than the last time... I would assume the manufacturer has much more accurate means of measuring fuel economy than the average Joe... However I wouldn't discount the average Joe because we all know OEM will inflate fuel economy numbers...

MPG is not a linear measurement. Gallons per 100 Miles is linear and differences can be compared accurately

120/1.925 = 62.338 MPG = 1.604 G/100M
120/2.000 = 60.000 MPG = 1.667 G/100M
That is a difference of 0.063 gallons (8.064 cups, which is just over 1 cup) of gas over 100 miles

320/10.925 = 29.291 MPG = 3.414 G/100M
320/11.000 = 29.091 MPG = 3.437 G/100M
That is a difference of 0.023 gallons (2.944 cups, which is just over a 1/3rd a cup) of gas over 100 miles.

I would not say that using .075 gallons of gas more on the 2nd tank makes a "huge difference" in fuel economy since it would only use 8 cups more gas over 100 miles. At those high MPGs, .075 gallons isn't that big of a deal, small tank or not. Its difference in fuel consumption between tanks vs the car was only 0.040 gallons (5.12 ozs, which is about 2/3rd a cup)

On the other hand, look at this example with a truck using the bike mileage to see how MPG isn't linear:
120 miles and fill up 14.925 gallons vs 120 miles and fill up 15.000 gallons
120/14.925 = 8.040 MPG = 12.439 G/100M
120/15.000 = 8.000 MPG = 12.500 G/100M
That is a difference of 0.061 gallons (7.808 ozs, or just under 1 cup)of fuel over 100 miles.

The bike had a difference of 2.338 MPG and 0.063 G/100M
The truck had a difference of 0.040 MPG and 0.061 G/100M

See how the difference in MPG doesn't mean a thing? The bike had 2.298 more MPG but used only 0.002 gallons (0.256 ozs, or about half a TABLESPOON) more fuel over 100 miles.

You have to look at fuel used over a set distance, not a distance traveled over a set volume.

[renault_megane_dci]

Real world FE of vehicles is very much dependant on the driver's skills and inclination.

Since all vehicles are tested and every vehicle manufacturer cheats as much as possible, I assume we can compare the numbers given to compare the vehicles to each other even if it is not easy to see those numbers on your fuel gauge.

[pepperedchicken]

never got much over 100mpg with my old honda metropolitan.. but ALWAYS wot everywhere and revving at stops lol

[Honda100]

^^^ I still have yet to average 100 mpg with my Metro, and I usually only use 3/4 throttle.

[stillsearching]

Well my biggest thing is trying to figure out what reasonable speeds give what mpg. Perhaps a larger displacement bike would actually get better mileage being capable of pulse and glide, whereas a 125cc that's running flat out to keep up at 60mph would do worse?

From running numbers and such it almost seems that if I were to get a 50cc scooter, I almost might as well just run a motorized bicycle - in minnesota we can have 2hp and run 30mph on a bicycle on the street, gas or electric. With the general cheapness of electricity where I am, that would defeat even the best scooters i'd guess in cost per mile without question though i'd still need a 50 mile range or hauling spare batteries with.

However I don't really want to take 2 hours per day commuting when i'm overworked as it is - a straight shot on the highway makes the total commute time just under 1 hour. So i'm still trying to find some bike solidly in the 75mpg or better in the real world at highway speed to do this run since at 50ish I might as well run a geo metro. It's seeming like the Ninja 250 might be one of the best fallbakc choices since it wont be overstressed and is about the smallest bike that can actually pulse and glide by what I can tell, everyone else needing hugely more displacement to do so. There are other 'cool' bikes cruisers and such that even at 125cc I wouldn't mind riding around in the slightest, but it seems they only are capable of better mileage at the slowest of speeds, and they aren't available any cheaper on the used market/everything still over 2k that i've seen.

So partly what i'm wondering now (as the topic shifts away from scooters afterall) is what kind of 'medium displacement' mpg figures are obtainable with P&G on a bike? Because that's a total topic change i'll start a different one along that line.

[alvaro84]

If 650cc complies your definition of "medium displacement", then you can look Teresa's log on the left of my posts. We get essentially the same FE with a 250cc Hyosung cruiser (GV250). Both run with the factory gearing.

[ciderbarrel]

Originally Posted by stillsearching

It's seeming like the Ninja 250 might be one of the best fallbakc choices since it wont be overstressed and is about the smallest bike that can actually pulse and glide by what I can tell, everyone else needing hugely more displacement to do so.

The 300 is fuel injected and will get better mileage. Plus you don't have to play with the choke and waste fuel warming up the engine.

[sendler]

Originally Posted by stillsearching

a straight shot on the highway makes the total commute time just under 1 hour. So i'm still trying to find some bike solidly in the 75mpg or better in the real world at highway speed

You have just described the Honda CBR250R. It is the only stock bike that can do that. A Rebel or a TU250 will be tapped out at 70 mph. The CBR is still singing. There aren't any used ones yet but there are some left over 2012's for about $3,800. Ninja250's can get close to 75 mpg and good used ones are around for $2,000 but I don't like carburetors. The new 300 is a nice bike with more power and fuel injection but won't match the Honda on fuel consumption and has less room around the tank for taller rider's knees.