The bike won't run without the red and black pair of wires connected up to the loom - they are for the fuel pump.

I think you may be confusing yourself a little with the three-wire potentionmeter connection issue!

In a basic sense there are basically three way to wire a pot.

(1) 3x wires - input, wiper and ground, which is used as a volume control as it will be "off" when grounded.

(2) 3x wires - input with wiper and ground connected together, so essentially it only has two connections as wiper and ground are linked.

(3) 2x wires - only using the input and wiper, which achieves a similar effect to (2), making a straight forward variable resistor. With this two connection method, whichever end of the track you apply the input will determine which way the resistance changes, either increasing or decreasing as the wiper moves along the track.



The fuel sender pot will be either (2) or (3). Regardless of which, it will only have two wires emerging from it - one (green) is effectively the input (12V) and one (black) the output (off the wiper) going to ground.

To connect a gauge (or voltmeter to act as a gauge) then it should be wired as in the diagram below. Remember you need to provide a new ignition switched 12V supply as the existing (green) wire supplying the sender comes from the dash panel (which you haven't got anymore!)



Just to reiterate, I do not know which way the fuel sender on the Tenere tracks (either up or down in resistance with float movement), I have not tested this. I also do not know what range of resistances it produces, as I haven't tested that either.

I would strongly recommend, before doing any of the above, setting your multimeter to 1K ohm and connecting the probes to the green and black wires on the sender unit and measuring the change in resistance as you add/remove fuel from the tank (unless you want to take the whole pump assembly out and move the float manually).

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