Any ideas on tracking fuel usage

[alexanderfoti]

Hi all

I have a superdream diesel with 2 tanks.

One has diesel in it, the other 50/50 veg oil.

The engine is started and stopped on Diesel, and when warm switched over to veg oil mix.

Issue is, how do I track my fuel economy with 2 tanks?

My starting/stopping tank is likely to last much longer than my diesel tank, and my trip meter counts regardless of the tank I use I was thinking a simple 12v trip meter would be good (And could be activated with the solenoid, but they dont exist)

I was thinking of using a bike computer and powering it from the switch (using step down circuit) but I think it will loose its settings when un powered.

Any ideas?

[BertTrack]

Bike computer indeed with the switch in the sensor wire. So that when the solenoid is activated the computer will pick up the signal from the wheel.

[coachgeo]

With that idea in mind..... two of them if it can be fitted. One is flipped on when on diesel and other when on Veg. Regular odometer becomes your "engine/bike" milage.

Granted if your in the mood for math games.... you only need the one bike odometer. Subtraction will give you the other.

[alexanderfoti]

Indeed, but tracking using subtraction requires that I note down when I change and that would entail stopping etc.

Just have to figure out a way to power them on via 12v, maybe a relay to connect the signal wire to the sensor on the fork that turns on when the solenoid activates

[alexanderfoti]

Sorry Bert, I didnt see your post before, Exactly the same thought process as me! Many thanks!

[alexanderfoti]

and if I use a SPDT relay, I can make it work with one sensor and magnet!

[Rhynri]

Flow rate meter for the fuel line? (The one after they join) Just an idea. Then you just have to go with the flow!

[alexanderfoti]

Just to let you know I implemented 2 bycycle computers, wired through to one sensor via an spdt relay in the sensor wire.

Its switched by the tank switch so when you have diesel selected the diesel bike computer counts and vice versa for veg oil tank.

An at the end of a tank, the dash and the computers are only off by 1-2 miles.