Bike Fuel Indicator - Inputs

What makes you think it "...is showing perfect reading/status of fuel."

Is the perfect status of the fuel supply required, or is a close approximation acceptable?

The most simple way they work is a float on a screw which was a small piece of twisted flat bar. As the float moves up and down with the level of the fluid. It turns the screw which points to the fuel level. The pitch on the screw could be changed to correspond to the irregular shape of the tank to show fuel level.

With electronics the float would change resistance on a pot. Which does not necessary need to be linear. Which could correspond to the fuel level.

Either way the are not a perfect reading of the fuel level, just close approximate.

I really don't know how they do it. But a level sensor and a look-up table should do the trick. (it can be programmed before breakfast)

Fuel level is measured by a float that rides on the surface of the liquid and sends a signal to the indicator. Tank configuration does not matter. Full is full, and empty is empty.

While your answer is correct, most drivers want to know how much fuel is left in the tank by volume, not elevation.

Fuel level is indicated by the readout of the guage, which is roughly calibrated to volume.

The float still rides on the surface of the remaining fuel in the tank, and it still gives an indication of how much fuel is in the tank.

I have driven dozens of vehicles and not one has had a fuel gauge that indicated perfectly, many were not even close! I simply reset the trip odometer when I fill up and know my range.

You can have a very accurate level indicator, but this tells you nothing of the volume of fuel in an irregularly shaped tank.

Not true. See Hendrik's reply. There will be tolerancing issues (as for everything in this world). If you had a fuel gauge but didn't have an odometer, would any of you be happy to trust the gauge. I reckon you would. In my experience gauges tend to be pessimistic (i.e. there is always fuel left at 'empty').

Every fuel guage I can remember seemed to move faster and faster the lower it got. Gas mileage estimated by the fuel guage reading looks really good with the top quarter tank, but not as good thereafter.

My 1980 Ford Granada was this way. It ran for 200 miles on the first half tank then only 80 -100 on the last half. I do have to say my 2000 Chevy Silverado was a little more consistent but not perfect either. Currently I am driving a 2011 Toyota Prius and it seems much more consistent. The gauge is a series of 10 marks similar to that of the antenna power indicator on a cell phone. Each mark represents about 1 gallon of gas. At an average of around 50 MPG it runs pretty darn close. Each time the OD shows around another 50 miles traveled a mark disappears. As for the older gauges such as those used in the Granada, I was told there is an adjustment screw to dial it in if you wanted to. I just left it alone. At 1/4 tank I'd start looking for a gas station. No low fuel light needed. Just common sense.

I would use a series of temperature compensated, full-bridge S-beam load cells at each mounting point of the tank, each buffered by a low-pass filter with a cut-off frequency of precisely 0.05 Hz, then connected to a multi-input ultra-low noise summing amplifier with both bias and gain adjustments to allow zeroing and full-scale set points, output to an over-sampled 5 and 1/2 digit precision voltmeter with NVIS back-lighting for those lights off blasts down the back-roads of a new moon.

Cheers !