Fuel Gauge Question

[BLUE MULE]

I've noticed that my fuel gauge doesn't seem very accurate. It seems bottom heavy. Ive been tracking my MPG and am getting about 26 MPG. I know it's more dependable to track my fuel by by milage than by the gas gauge so I always set my trip meter when I fuel up, but a good example was when I filled up today my gas gauge was at a little over a 1/4 tank but I only put in 2.6 gallons to fill it up. I looked in the tank and it was full so no problem there. Just wanted to know if this was common on the Spyders. Has anyone else run into this? The gauge seems fine otherwise no bounce or anything like that.

 

[NancysToy]

This is common on a lot of vehicles, not just the Spyder. Yours seems to be a bit extreme, but everybody fills a little differently, so where you put in 2.7 gallons, another rider may put in 3.1 or some such. I have been putting in about 3.8-4.2 on my 2011 RTS at the low fuel warning, which comes on at about the red., so what you are seeing is typical.

 

[IWN2RYD]

+1 With what Scotty has mentioned...

Just in case you want a little bit more accuracy, many if us have simply taken 10 moments of our time and unplugged the Temp and Fuel gauge right off the back of the gauges themselves...

Then the original "Digital" version on the Color Screen shows these! Even the temp has colors... Starts off yellow, goes orange, and then RED in very bad oh no moments... Of which I have not ever seen, but I am told the RED is there :thumbup:

I now put consistently 4.7 Gallons in our RT-S at two bars from the bottom (About ten show up on the "Digital Dash")....

 

[Yeochief]

Gas gage

Last Monday :spyder2: and I went for a ride. Had around 100 miles on the tank of fuel. Rode until the little gas pump lite up and continued until there were no bars on the gage. Finally at 170 miles I gassed up. Took 5.7 gallons. The light seems to come on at about 120 miles or so, best to use the odometer. I'm averaging 29-30 mpg riding at less than 65 mph, mostly urban, not much open road where I've been so far. After I get my 625 mile service, I hope for a long open road trip to get an idea of mileage when cruising.

 

[spydee owner]

This is common on a lot of vehicles, not just the Spyder. Yours seems to be a bit extreme, but everybody fills a little differently, so where you put in 2.7 gallons, another rider may put in 3.1 or some such. I have been putting in about 3.8-4.2 on my 2011 RTS at the low fuel warning, which comes on at about the red., so what you are seeing is typical.

One would think that in 2011 a gas gauge on a vehicle could provide a more accurate reading of what is actually in the tank. And, like you said it happens on many many vehicles. The nice thing with the spyder is that when you run out of bars on the gauge, there is still approx 4 litres in the tank (1 U.S gallon approx)

 

[ThreeWheels]

One would think that in 2011 a gas gauge on a vehicle could provide a more accurate reading of what is actually in the tank. And, like you said it happens on many many vehicles. The nice thing with the spyder is that when you run out of bars on the gauge, there is still approx 4 litres in the tank (1 U.S gallon approx)

Honestly ?? I think it's some kind of bias in the engineering department.

This is the only vehicle BRP makes where gas is available within a short time of the low level light coming on.

Everything else is an off road vehicle. Running out of gas in the middle of the Artic tundra is more problematic than running out of gas on Rt 95.

Just my humble opinion.

 

[Mr. White]

Mr. Mule. I get 29-30 mpg. I reset my odometer at each fill up and at 130-140 or so, I start looking for a station. My gauge goes to rock bottom at 110-120. My fuel light has never come on, but I have never gone over 150 miles. At 150 miles, I will take 5.0-5.2 or so.

:spyder2:

 

[NancysToy]

One would think that in 2011 a gas gauge on a vehicle could provide a more accurate reading of what is actually in the tank. And, like you said it happens on many many vehicles. The nice thing with the spyder is that when you run out of bars on the gauge, there is still approx 4 litres in the tank (1 U.S gallon approx)

Honestly ?? I think it's some kind of bias in the engineering department.

This is the only vehicle BRP makes where gas is available within a short time of the low level light coming on.

Everything else is an off road vehicle. Running out of gas in the middle of the Artic tundra is more problematic than running out of gas on Rt 95.

Just my humble opinion.

I guess you guys can dream up conspiracies, and talk trash about engineers all you like, but there are solid mathematical and engineering reasons for this effect. Fuel tanks on motorcycles are not uniform shapes...much worse than cars, which also have volumes that vary with depth. The tank float actually measures depth, where an inch might represent a half gallon at the top, and a gallon at the wider bottom. There is no magic way of converting this, although it is theoretically possible to map it and adjust the gauge electronically. An analog gauge cannot be mapped in that way. Maybe this is 2011, but the principles behind analog gauges go back to the 1930s or earlier. In addition, a swinging fuel float (the most common kind) changes resistance more for an inch of depth change in the tank at a certain place position, than it does in another. That is due to the geometry and angles involved. Finally, all gas floats must hang free above the bottom of the tank, so they read at the minimum prior to actually being out of gas on a tank that drains relatively completely. The gauge fails to respond below this point...yielding a reserve. No magic bullets, no electronic gizmos. If you want more accuracy, revert to your digitals, but even those have limitations. You probably couldn't afford a gas gauge with pinpoint accuracy.