Fuel gauge?

[tbishop11]

Hey does anybody know what the ohms for the fuel sender are? And also if there is any sort of a after market gauge that will work? It's for a 79 xs11 but I'm not sure if it's the original tank?

[Larrym]

For the senders mounted in the fuel tanks-------

If you're talking about a standard tank which sends to a "real" gauge:

a. Full---6 to 10 ohms
b. 1/2---28.5 to 36.5 ohms
c. Empty---75 to 85 ohms.



If you mean the special which just turns on a red light then:

1,500 ohms plus/minus 100 ohms at 77 degrees Farenheight.

Taken from the Clymers repair manual.

I dunno about an aftermarket but that doesn't mean someone else here does..

[tbishop11]

Thanks! At least now that I know the range I can see what I can find!

[fredintoon]

Hey does anybody know what the ohms for the fuel sender are? And also if there is any sort of a after market gauge that will work? It's for a 79 xs11 but I'm not sure if it's the original tank?

Hi Shop,
I got one spare. Yours for postage. PM me your mailing address.

[tbishop11]

Hey Fred,
I really appreciate it, I've just got to figure out if I got the light or the gauge kind? I'm not using the stock gauges any more so I'm not real sure what I had plus everything had been mixed and matched on the bike I'm pretty sure that my tank wasn't original, but it does have the sender? I'm also not sure if the gauge sender in the tank is even functioning? I've got to run in to work right now (grave shift ) but I'm guessing now that I know the range of ohms for each I should be able to figure it out and get back to you. I'm almost hoping that it's just a light because then I could mount a little led light on the handle bars or something, that way I wouldn't have to steal your gauge?
Thanks Again,

[Larrym]

Wattage matters

tbishop11,

If the tank you're talking about is the same one that is currently shown on your home-page: Black with the filler cap offset to the right, then you have the special version.

Hopefully the thermistor inside is in good shape and therefore works. A small bulb of the same wattage/size as was in the original gauges would work fine. Larger and brighter bulbs may either overload the thermistor in the sending unit or just not be bright enough to see.

All this goes out the window if there's a sending unit inside that tank which has a lever arm and float though:Totally different method.

[fredintoon]

Hey Fred,
I really appreciate it, I've just got to figure out if I got the light or the gauge kind? I'm not using the stock gauges any more so I'm not real sure what I had plus everything had been mixed and matched on the bike I'm pretty sure that my tank wasn't original, but it does have the sender?

Hi Shop,
Mix'n'match, eh? Me too. My Special has a Standard tank because I place a Standard tank's fuel capacity ahead of a Special tank's looks.
The swapover needs the Special's thermistor fuel sender (it's a little round can of a thing) to work with the red eye in the Special's round tach.
This leaves me with two (one is really rusty, the other is OK) of the lever/float/rheostat type Standard fuel senders that the bike will never need.
Your site shows that your chopper started out life as a Standard but the tank cleansing shots show me a Special tank which means it should have a thermistor sender in it.
Check it by hooking it up to a battery and a small bulb.
Dump the sender in a jar of gas, the sender only conducts when it's dry so you should see the light go out once it's wet. May take a few moments to work.

[TopCatGr58]

Hey Bishop,

Don't want to rain on your parade regarding the LED light idea, but it won't work.....because I already tried it on mine! The thermistor allows too much current to leak thru it, so the LED which takes very little power will light up ALL THE TIME. A standard type incandescent bulb works because only when the fuel gets low, allowing the thermistor to heat up and then release/send much more current to the bulb circuit to let it light up. I had replaced all of my gauge lights....Hi beam, Neutral, and Low Fuel lights with LEDs, and the RED EYE was on all the time. Switched it back for a regular bulb, and it worked like it was supposed to!

T.C.

[tbishop11]

Thanks everybody!

Larrym,T.C and Fred I'm glad that you let me know about the wattage. Because that saved me the time of installing the led light. I almost bought a speedometer here part number Part #03-0744 that had the led lights in the gauge and I was just going to wire it to that but now I'm glad that I didn't. Fred I'm going to be checking that out today to see if I can get a bulb to light up or not. The previous owner snipped the wires out of the harness for the plug that goes to the thermistor, so I'm guessing that really all I need is a wire that is hot when the key is on and a ground for the bulb for it to work? However that fact that those wires were snipped leads me to believe that there's going to be a problem with either the wiring or the thermistor, so I'm glad that you told me how to test it. So I guess that's my agenda for today until I've got to go into work this evening.

[fredintoon]

- - - Fred I'm going to be checking that out today to see if I can get a bulb to light up or not. The previous owner snipped the wires out of the harness for the plug that goes to the thermistor, so I'm guessing that really all I need is a wire that is hot when the key is on and a ground for the bulb for it to work? However that fact that those wires were snipped leads me to believe that there's going to be a problem with either the wiring or the thermistor, so I'm glad that you told me how to test it. So I guess that's my agenda for today until I've got to go into work this evening.

Hi Shop,
I'm guessing here. You got that bike as shown in the first pics on your site? A Standard with square gauges but with a Special tank on it?
Thing is, a thermistor sender will NOT work with a Standard's fuel gauge.
Betcha that either the PO found that out the hard way and snipped the wires in a fit of temper or that he got the tank from a bike breaker with the wires pre-snipped.
I'd say you have a good chance that the thermistor still works.

[BigDick]

Hi Shop,
I'm guessing here. You got that bike as shown in the first pics on your site? A Standard with square gauges but with a Special tank on it?
Thing is, a thermistor sender will NOT work with a Standard's fuel gauge.
Betcha that either the PO found that out the hard way and snipped the wires in a fit of temper or that he got the tank from a bike breaker with the wires pre-snipped.
I'd say you have a good chance that the thermistor still works.

fred, does this mean that a normal fuel gauge (by that I mean one that shows the level rather than just a light for low) won't work with the special's sender? Is there some way a person could rig a fuel gauge to show the level on a special? Can you just swap sending units? Sorry for the hijack.

[CatatonicBug]

fred, does this mean that a normal fuel gauge (by that I mean one that shows the level rather than just a light for low) won't work with the special's sender? Is there some way a person could rig a fuel gauge to show the level on a special? Can you just swap sending units? Sorry for the hijack.

That is correct, and no, the Special's sender will not work for the guage on a standard. The Standard guage is analog (varying display), and the Special's is digital (on/off). I believe it is possible to put the Standard sender in a Special tank, to allow the use of the Standard guage, if that is what you want to do.

[BigDick]

Yeah, I'd like to have an actual gauge just for s's and g's. Mine works just fine and I know that about every 100 miles I need to fuel up, but I'd just like to have a gauge that shows the actual level of fuel.

[andreashweiss]

The std and special use different systems that do not interchange. The larger sending unit from the std tank will not fit inside the smaller special tank, remember usually the regulater in the standard square tach is the fault, ,the gas tank sending unit rarely fails, I have both , a std tank sending unit and a standard square tach if anyone needs those parts, thanx andreas

[fredintoon]

fred, does this mean that a normal fuel gauge (by that I mean one that shows the level rather than just a light for low) won't work with the special's sender? Is there some way a person could rig a fuel gauge to show the level on a special? Can you just swap sending units? Sorry for the hijack.

Hi BigDick,
the thermistor sender works as an on/off switch. It can't operate a gauge that needs a variable current to function.
OK, the sender mounting plates are identical but the holes in the tank tunnel are on opposite sides so to put a Standard sender in a Special tank it'd have to go in backwards or it'd be upside down and I don't think it'd fit like that.
You'd also need a separate fuel gauge.
Or you could swap in a Standard tank & square tach with a gauge in it?