Fuel Gauge Accuracy

[tecman77]

nice exercise wessie!

[wessie]

Just one note, I put the bike on the main stand to get the 18 litres in

[advman]

 
 

As the Tracer is meant to be a touring bike, I was curious to find out the tank range. So, over the last couple of days I have carried out an experiment. 1. Tank brimmed whilst parked on side stand
2. Rode around mostly rural roads
3. Observed fuel gauge stay at full for 112 miles
3. Did a further 67 miles until the E flashes and the F guage appears i.e. 179 miles.
4. Stuck a 4 litre can of petrol in the topbox
5. Continued to ride, & ride, & ride. I got bored when the F gauge indicted 40 miles and pulled into an Asda fuel station.
6. 17.99 litres of unleaded fuel added.
 
So, Yamaha are very pessimistic about the fuel range and give you a huge 22% extra mileage after the reserve is indicated.
 
The bike will comfortably do 200 miles to a tank - remember I fuelled up with the bike on the side stand.
 
I've no idea what the economy was for the journey as this is not a worry, apart from how it affects range. All I wanted to know is how many miles can I safely do on reserve and does this bike, claimed to be a touring bike, have a genuine 200 mile tank range. The other matter established is that the tank definitely has an 18 litre capacity and I was close to conking out before I pulled into the petrol station.
 
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. That's good to know

 

[mikef]

Mine does this like the reviewers noted.  I keep a close eye on the trip meter.  

[hotboot]

I have gotten 190 mile tanks and the fill was 4.3 gallons. The blinky reserve light can be defeated by cycling the screen toggle. I fear summer reformulation of fuels in Texas will kill any hope for a 200 mile range. Mileage is unchanged from break in to WFO now at 1300 miles on the odo.

[papac2000]

Whenever possible I try to insist on selecting fuel from pumps that say "Contains no ethanol". There are a few retailers locally that I frequent for that reason. It effects fuel consumption considerably. Not an option for everyone I gather.

[ULEWZ]

As the Tracer is meant to be a touring bike, I was curious to find out the tank range. So, over the last couple of days I have carried out an experiment. 1. Tank brimmed whilst parked on side stand
2. Rode around mostly rural roads
3. Observed fuel gauge stay at full for 112 miles
3. Did a further 67 miles until the E flashes and the F guage appears i.e. 179 miles.
4. Stuck a 4 litre can of petrol in the topbox
5. Continued to ride, & ride, & ride. I got bored when the F gauge indicted 40 miles and pulled into an Asda fuel station.
6. 17.99 litres of unleaded fuel added.
 
So, Yamaha are very pessimistic about the fuel range and give you a huge 22% extra mileage after the reserve is indicated.
 
The bike will comfortably do 200 miles to a tank - remember I fuelled up with the bike on the side stand.
 
I've no idea what the economy was for the journey as this is not a worry, apart from how it affects range. All I wanted to know is how many miles can I safely do on reserve and does this bike, claimed to be a touring bike, have a genuine 200 mile tank range. The other matter established is that the tank definitely has an 18 litre capacity and I was close to conking out before I pulled into the petrol station.
 
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.

That is very good information to know. For us in the Colonies, that is 46.1 MPG with a total range of 219 miles. Pretty impressive. Just for giggles, did you happen to notice what the computer read for MPG or however you have it set? Just trying do get another review of the accuracy, as others have noticed a few MPG difference. I will probably never go that far before stopping, but 200 safe miles on a tank is good to know if I have to go that far.
 

[wessie]

No, I didn't register the MPG reading. Tank range in normal everyday riding is all I wanted to know, regardless of whether the tank holds 15, 18 or 22 litres.

[pont]

This is a case of Yamaha phucking up the UI.
 
*ALL* gas gauges do this, to an extent. Even on cars. They've found, through research, that customers actually prefer their fuel gauge to stay on FULL longer after they've filled up. It gives them a feeling of more fuel efficiency.
 
Where Yamaha screwed up was making it obvious that they're doing this by making a big single block for the first segment. Totally defeats the purpose of that reassuring stay-full effect. I find it induces uncertainty instead.

[jimf]

Where Yamaha screwed up was making it obvious that they're doing this by making a big single block for the first segment. Totally defeats the purpose of that reassuring stay-full effect. I find it induces uncertainty instead.

I gotta believe you'll get used to it; one of the cars I owned had a rather over-dramatic difference in apparent fuel burn rate and I just learned that "half" full really means to start thinking about refueling, the low-level light will pop on fairly soon.  I'm so used to using the odometer for range on the bikes that it won't make any difference to me. 
Heck, on a rented Versus 650 I used the odometer despite not knowing what its range was.  170 miles on the clock by the time I got to Taft in the CA central valley?  Yea, I suppose I should get some gas.
 
And really, really good Mexican food too.
 
Sidebar:
 
Getting to Taft from the coast via route 56 was really, really fun.  I mean, really fun, even with the Versys' mediocre suspension pushing hard on every bumpy sharp right corner making it a little sketchy at speed.  It's too bad I didn't learn about Rossi's Driveway until the next day.  Damn I love California.  So much I'm hoping that sometime in the next few years I can ride coast-to-coast just to ride that stuff on my own bike, although that might be a pipe dream in terms of how much time it would take.
 
While I was eating that awesome Mexican food my wife, back in Boston, sent me history lessons about Taft via text message.  That used to be the headquarters of Standard Oil, and there are miles and miles of oil fields right outside of town.  This east coast boy had never seen anything like that, not even while mountain biking through the Bakken fields in North Dakota.
 

[jimf]

Many motorcycle tank fuel gauges work this way. It has, mostly, to do with the shape of the tank. Fat at the top, thin at the bottom. Because there is more volume and surface area at the top of the tank, it takes longer for the float to register a decrease in volume. Or in other words, the float moves linearly, but the volume does not decrease linearly.

Yea, but you're not talking about a direct connection between the float and a fuel level needle.  There's a digital mapping between the float sensor and the LCD display segments.  Building a nonlinear mapping so that the fuel level display gives you a reasonably accurate display would be the work of minutes in software, it's just a lookup table (versus a linear function). 
I can think of a few reasons why Yamaha might have done it the way they did, including lower costs for the LCD since every segment costs money (for the life of me I don't know why they're not all using bitmapped LCDs for the flexibility and economies of scale!) or limited resolution of the fuel level sensor.
 
 

[Guest dmizer]

Yea, but you're not talking about a direct connection between the float and a fuel level needle.  There's a digital mapping between the float sensor and the LCD display segments.  Building a nonlinear mapping so that the fuel level display gives you a reasonably accurate display would be the work of minutes in software, it's just a lookup table (versus a linear function).

 
Well, I was mostly talking about motorcycle fuel tanks in general, not the Tracer's tank specifically.
 
Either way, the important point is that you need to know your total tank range and keep track of it with the trip odometer rather than relying on the fuel gauge.

[glenview09]

After 6 years of owning a mts1000 multistrada I'll just be glad to not have the gauge register empty at 80 miles when there are 40+ miles left in the tank. the mts tank extextends under the pillion and is definitely non linear but the main problem is that the fuel sender does not even extend to the bottom of the tank.
 
Hopefully it will be pleasure to own something designed by the Japanese rather than the Italians.

[basstodave]

My fuel gauge goes from full to half at about 105 miles. I thought it was a gradual display but I guess it works in blocks. Does your gauge work similarly, showing same accuracy or lack thereof?

[wessie]

My fuel gauge goes from full to half at about 105 miles. I thought it was a gradual display but I guess it works in blocks. Does your gauge work similarly, showing same accuracy or lack thereof?

I moved your post here, and you can see from the length of this thread the answer is most definitely YES. 
If you notice any other idiosyncrasies with your new bike please search the forum as you will probably find the answer is already here somewhere - just click the search link under the banner at the top of the page.