Hi

 

I have a Yamaha Nouvo SX. The data sheet says, the tank volume is 4.3 liter. The electronic display on the vehicle shows me an average consumption of 2.6 liter / 100 km. With that, I should  drive around 160km. But after 120km my tank is empty. May be I could drive another 10 km. But surely not another 40km.

 

Gives me the display wrong information?

 

 

Get a 2 litre gas can. Fill up bike. Ride until empty. Empty gas can, drive to nearest station and fillup. Note km ridden. Viola - answer.

EDIT: sorry I was interrupted and it took me more than 52 minutes to complete my answer.

 

Fill a  water bottle with petrol and place under the seat. Fill tank with petrol and ride.  When gauge shows empty write down the mileage, when bike stops write down the mileage.

 

This will tell you 3 things

 

Motorcycle range

MPG

Distance with "reserve" Ie the distance the bike will travel after the fuel gauge registers empty.

 

If you want to subsequently know the reserve volume you simple ride the bike until the gauge shows empty, fill up and work it out.

 

 

 

As a first step you can also look up how big the reserve is in the manual of your bike.

 

Pretty sure that the reserve is at least 1L and at 2.6L/100km you should be able to ride 35km. A PCX for example has a 1.5L reserve. A fuel reserve should get you 30-40km because 10km would be too dangerous in terms of leaving you stranded somewhere as distances between gasoline stations can easily exceed that. And note that the 120km you get until the gauge flashes (I assume that's what you actually mean by "empty") plus 40km would get you to the 160km you had expected.

 

But to double check the real world values, you can do the test with the bottle that VocalNeal suggested. Note that fuel consumption can vary heavily depending on the kind of riding one does.