Fuel Gauge Accuracy

[basstodave]

Thank you Wessie!

[falcophil]

Well i did 172 miles on my first tank and needed 15 ltrs dead when i brimed it, gauge had one seg left & not flashing.
MPG works out to 52, but reading said 56.2 so showing more than its doing- not unexpected. running in so below 5000 rpm with the odd blip above, also damp roads so recon it will dip below 50 MPG once it gets going a bit. still a good tank range though- could have probably gone to near 200 miles.

[caribou]

I usually do between 250 and 300 km before switching to reserve. That equals to about 15 liters of refuel.
Bike is calculating avg fuel consumption of 4.6 L/100km, but by my calculations it's somewhere around 5 L/100km.
 
btw, I'm using only 100 octane petrol and will switch to 95 in few months just to compare what's what

[Guest dmizer]

I'm using only 100 octane petrol and will switch to 95 in few months just to compare what's what

The absolute highest rated fuel I can get here is 91. The bike should be fine with 95, but I'm certainly jealous that you have access to 100.
 
Edit: Japan uses RON measurement for octane rating.

[wessie]

I'm using only 100 octane petrol and will switch to 95 in few months just to compare what's what

The absolute highest rated fuel I can get here is 91. The bike should be fine with 95, but I'm certainly jealous that you have access to 100.

Are we talking RON, MON or AKI numbers? Folks need to remember this is an international audience so state your units! 
Shell V Power 100 RON common in the parts of Europe is only 87 MON or 94 AKI
 
Even supermarkets sell 97 or 99 RON fuel in the UK.
 
I just follow the sticker on the tank and use 95 RON. Seems to go quite well, even on the Asda (Walmart elsewhere) variety.  
 

[caribou]

The absolute highest rated fuel I can get here is 91. The bike should be fine with 95, but I'm certainly jealous that you have access to 100.

Are we talking RON, MON or AKI numbers? Folks need to remember this is an international audience so state your units! 
Shell V Power 100 RON common in the parts of Europe is only 87 MON or 94 AKI

 
Was talking about 100 RON. I believe RON is commonly used in Europe.

[papac2000]

Just to complicate things, in Canada our fuel ratings are RON+MON/2. We can commonly get 87, 89 and 91 octane. A few places have 94. I try to stick to the places that state their premium fuels CONTAIN NO ETHANOL on the pump. Just for reference, our 94 octane is 101 RON.

[wessie]

Just to complicate things, in Canada our fuel ratings are RON+MON/2. We can commonly get 87, 89 and 91 octane. A few places have 94. I try to stick to the places that state their premium fuels CONTAIN NO ETHANOL on the pump. Just for reference, our 94 octane is 101 RON.

your rating is the same as the AKI system I quoted above 
In the UK we cannot get any information about ethanol content other than "it may contain up to 5% ethanol" - under EU law they only have to declare the ethanol content if it is over 5%, hence the E10 grade, which is quite common in France. Like you I try to avoid the E10 when abroad as it means fewer miles per tank.
 
A friend went to look at an Aprilia Futura tourer which would have been ideal for his needs, except it had a mis-shapen tank from the ethanol. Quite a rare bike so no aftermarket suppliers.

[tilk]

Note, I was using UK spec. Esso regular unleaded fuel. This is 95 RON and will contain up to 5% ethanol. When in France, where they use mainly E10 fuel I will be lucky to get 200 miles to a tank.

 
Just a quick comment on this subject: While in France, use Unleaded 95 (without Ethanol) or 98 as it is strongly recommended by every Yamaha dealer here and even by Yamaha Motor France techs. Unleaded 95 E10 (10% Éthanol) is "tolerated if you can't find Unleaded 95/98".

[oldfart]

When I bought my 2000 Ninja ZX-11 it was the first bike I'd ever had with a fuel gage. It read full for the first half of a tank, plunged down visibly during the third quarter of the tank and read bone dry for the last 25 percent. I always used the trip odometer to know how much gas I had left (still do, I still have the bike). What a bummer to see that, 15 years later,  my 2015 FJ-09 operates in exactly the same way!

[wessie]

Note, I was using UK spec. Esso regular unleaded fuel. This is 95 RON and will contain up to 5% ethanol. When in France, where they use mainly E10 fuel I will be lucky to get 200 miles to a tank.

Just a quick comment on this subject: While in France, use Unleaded 95 (without Ethanol) or 98 as it is strongly recommended by every Yamaha dealer here and even by Yamaha Motor France techs. Unleaded 95 E10 (10% Éthanol) is "tolerated if you can't find Unleaded 95/98".

your unleaded 95 RON may contain ethanol. Under EU law a petrol producer can add up to 5% ethanol without declaring it. 
My friend is an area manager for Shell retail, overseeing many dozens of franchised sites. He states you never know how much ethanol is in 95RON unleaded. Could be zero, could be 5% or something in between as it all depends on which refinery blended the base stock to which Shell then adds their additive package. Shell will buy base stock from anywhere, even made by BP, Total or Exxon if they can save a few fractions of a penny per litre. 
 
As the mate had a bike with a plastic tank that did not like ethanol, when he started with Shell he did some research and the chemists told him the best way to avoid ethanol in your tank is to use super unleaded which has a 97 to 100 RON in the UK and may be sold under brands like Shell Vpower or Tesco Momentum99. This applies across Europe apparently as petrol recipes are controlled under EU directives. 

[tilk]

I'll stick to super unleaded 98 then ! Thank you for this explanation, I had no idea they would add ethanol in other "mixes" than 95 E10.

[ctrlaltdl]

My first full tank, I went 194 miles. I filled up while on side stand at 4.3 gallons. The computer said 48MPG, but my calculations are 45. The computer seems to be 6-7% optimistic.

[Guest dmizer]

After having completed a 4000 km 9 day tour, I think I have the gauge worked out. The first part of the tank doesn't need to be precise because most people don't pay that much attention to the fuel gauge after a fuel stop. The part that matters is the last half or third of a tank when each segment represents about the same amount of distance. I am seeing about 20 to 30 km per segment after the first segment disappears. It's easier to get a rough estimate of your remaining range this way.

[tecman77]

Myself and my work colleague, we went last weekend to Wales. We did about 550 miles in 2 days and we didn't save our Tracers at all. My fuel consumption was about 55-58mpg according to onboard computer. The best range I got so far without running dry was 185 miles. When refuelling I put 15.5 liters, so there was at least 3 liters left before going dry. That means that doing 200 miles is not a problem, but margin is rather small, especially if you are touring and you are on motorway where services are not very often.