The most accurate Fuel Gauge you will ever find ...

[DEcosse]

Some of you might want to skip this post if it makes your brain hurt!

Just to give a little more detail on how it it is calibrated after its very first use for any bike/car:
The first value you enter is the specified capacity for the tank (from your owners or service manual);
You then fill the tank initially (to the neck so you have an exact reference point), reset the system and then ride to consume the tank;
- it does not really matter how much you consume but at least 100 miles would be recommended - or even a full tank.
(You will be ignoring the values on the display at this point until after you complete the initial calibration.)
Then after that initial ride & at gas station, record the displayed total time that the injector has been in the 'on' state since that earlier refill - the InjctmS number shown in the display.
Ex: 1548307 (that is in ms )
Then you fill the tank back to the neck (so you know exactly how much gas was consumed) & record how may gallons it takes to fill the tank, off the pump. Ex 3.274gal.
Divide InjctmS by Gallons to get mS/Gallon. Ex: 1548307/3.274 = 472909 - this number is a direct correlation of the injector pulse time to volume of gas through it*
Then you enter that new mS/Gallon number into the appropriate field and from then forward it will accurately calculate the fuel being used and the other derivatives of that (% full, used, remaining, distance estimate etc)

* In actuality that constant that was created is not the volume of gas through that ONE injector, but through however many injectors that particular bike has; the number of injectors is actually immaterial for the purpose of this calculation, the computer simply calculates that for the given injector duration of cylinder #1, the bike used 'n' gallons of fuel overall. So you are not creating a constant of pulse duration to gas used in one injector but for all injectors (regardless of how many injectors that really was).
The premise assumes that the fuel being consumed (and the accumulated 'on-time') is approximately the same for each injector - & empirically you will find that it is indeed, giving repeatable results easily within the spec'd +/- 2% just by measuring the single injector alone.

For those of you that like math (I do - I know, I'm a sick puppy ) you can work the numbers backwards to get the real flow rate of the injector
Now, I know those values in the example above came from a Twin (Dave's base development all done on an SV650)
So the 1548307ms (= 25.805 mins) of that single injector related to 3.274 gals of fuel used for BOTH cylinders, so that one cylinder actually used 1.637 Gals - or 6197 cc's
So 6197ccs => 25.805 mins
or 6197/25.805 = 240 ccs/min which is the value of the Injector Flow Rate.
None of this calculation is actually processed, I'm just illustrating the accuracy of the system which results in the actual injector flow rating of the bike's injector.

There is a similar user-programmable entry for the odo which is calibrated for the speed sender for the particular bike/car, which then is used to calculate the mpg, and distance gone/remaining values

 

[Zonechamp]

Makes sense. The pump doesn't have variable pressure and the injectors are either open or closed. So I can see how measuring fuel that way would work. Great idea, thinking outside the box.

 

[rocketjohn]

I contacted TeeRiver and mentioned you DEcosse as the potential instigator of a great demand for this gadget from Triumph owners!

 

[DEcosse]

TeeRiver - Dave - is an awesome guy - fabulous support for an excellent product.

 

[barbagris]

A friend of mine has developed a Fuel Gauge that has amazing accuracy all the way throughout the range. It's called the FuelBot2.0.
It started off specifically for the Suzuki SV650 but has evolved to something that is now universal - for cars as well as bikes! (well as long as they are EFI )
The original thread is - the developer (Dave) goes by screen name TeeRiver.

I thank you sir. Had a major shock on a run last year (I was going a wee bit fast) - hit reserve 50kms earlier than usual on the odo and in "no fuel here" country.

 

[DEcosse]

Just a heads-up if anyone tries to contact Dave - he left this morning for the WSBK races so might be out of email commission till after weekend.
The Mrs and I are also heading down there

 

[Joesmoe]

Thanks for the heads up. Have fun !

 

[barbagris]

Speed is measured by gps on your chart plotter and the factory gauge use a vacuume pick up for speed, very inaccurate. The reason I ask is the our corn fuel is even more suspect on the water, than on land. It would be nice to know your burn rate so you could run you tank down low and then fill up with what you need especially at the same end of the season when you want your tanks as close to empty as you can. Fuel gauges on a boat are very inaccurate, and a factory fuel flow management system are very expensive.

I thought it might be GPS Jag - the system uses the raw pulses from a speed sender, where x number of pulses equates to distance (so it's not really interested in speed, its just the odo function for distance traveled)
So needs a conventional speed sender to use the distance and mpg displays
You would still have the Fuel Level (%) and Fuel Used (gals) and Fuel Left (Gals) which would still be really accurate and that is maybe all you need?

A quick solution - Hummingbird in Australia do a GPS speed sensor that outputs pulses based on speed. Hummingbird Electronics Pty Limited

I use one on my R3 to drive a second speedo and Speed alert system based on revcounters. Ken likes maths - so do I.

I'd would use the one with Bulkhead antenna esp on a boat. The new "mini" with fixed 5000 pulses per km is probably fine. I have the OLD one. The refresh rate on the larger ones is higher.

 

[DBR3T]

Got a FuelBot 2.0 on order. Gonna slap it on a 2008 R3T.

 

[DEcosse]

Awesome DRR3T - be sure to do a report on it when you get it - some pics of your install (both the mounting and the electrical connections) would be big help for anyone following suit.