Clutch's 1982 KZ750 E3 Cafe

750steve wrote:

clutch wrote: It doesn't look like your bike has a low fuel light. Here is a wiring diagram for the 77 B2:

kzrider.com/filebase/cat_view/95-1977/107-kawasaki-kz-750-b2

Aw balls.....that'd be my luck ok, didn't think it had but had my fingers crossed anyway! Is a retro fit possible within the skill range of a numpty??

I'm sure it can be done, but probably not easily. You would either need to drill holes to put the sensor in your tank, or buy a tank that has it (and hope it fits your bike).

Screw that, it'll do rightly!

The Reserve tap can be my guide :lol:

750steve wrote: Screw that, it'll do rightly!

The Reserve tap can be my guide :lol:

Been a while since I had that low fuel light even wired up. If I remember correctly, most times I would need to switch to reserve before it even came on. LOL!

clutch wrote:

750steve wrote: Screw that, it'll do rightly!

The Reserve tap can be my guide :lol:

Been a while since I had that low fuel light even wired up. If I remember correctly, most times I would need to switch to reserve before it even came on. LOL!

Ummm....your bike must have been built in Ireland! :lol:

Right, apologies, i've hijacked your bike thread & just realised it.

750steve wrote:

clutch wrote:

750steve wrote: Screw that, it'll do rightly!

The Reserve tap can be my guide :lol:

Been a while since I had that low fuel light even wired up. If I remember correctly, most times I would need to switch to reserve before it even came on. LOL!

Ummm....your bike must have been built in Ireland! :lol:

Right, apologies, i've hijacked your bike thread & just realised it.

It's ok. We're having some good convo

clutch wrote:

Motor Head wrote: So it is staying ON? That might be because of the small resistance still in the Thermistor. Maybe wire it up to either a relay or a transistor to switch it, on/ off.

Ok, I consider myself to be pretty good at wiring things, but I'm no electrical engineer. LOL! :silly: Can you explain how I would wire the relay or transistor to fix the problem? Also, would one of those inline resistor thingies (that's the technical term :woohoo:) that are used to run led turns with stock flasher units possibly solve the problem as well?

EDIT: It should definitely have been OFF with all the gas I had in it (probably about 3 gallons), so I'm thinking maybe the LED issue is the problem.

Are you still working this out?
If so here is a web page that can help you set up a simple common Transistor as a switch for a low current application: www.rason.org/Projects/transwit/transwit.htm
If you do the Transistor set up, you could be hiding it away inside of the Instrument or other spot, cause it would be small.
Or you could go with a Automotive relay like this one, I have here. Or you could get a micro relay for about $3 from The Shack.

Motor Head wrote:

clutch wrote:

Motor Head wrote: So it is staying ON? That might be because of the small resistance still in the Thermistor. Maybe wire it up to either a relay or a transistor to switch it, on/ off.

Ok, I consider myself to be pretty good at wiring things, but I'm no electrical engineer. LOL! :silly: Can you explain how I would wire the relay or transistor to fix the problem? Also, would one of those inline resistor thingies (that's the technical term :woohoo:) that are used to run led turns with stock flasher units possibly solve the problem as well?

EDIT: It should definitely have been OFF with all the gas I had in it (probably about 3 gallons), so I'm thinking maybe the LED issue is the problem.

Are you still working this out?
If so here is a web page that can help you set up a simple common Transistor as a switch for a low current application: www.rason.org/Projects/transwit/transwit.htm
If you do the Transistor set up, you could be hiding it away inside of the Instrument or other spot, cause it would be small.
Or you could go with a Automotive relay like this one, I have here. Or you could get a micro relay for about $3 from The Shack.

I haven't messed with this yet. I was working on fixing the leaky petcock adapter first. So if I run this setup, the ground wire from the indicator light just gets grounded to the frame/battery?

With the relay or transistor. The bulb ground would be to the frame, if you are switching the Power with the added device. Or you can switch the ground to the device. Either way. Control the ground or the power. The Latch coil of the relay, to trigger and close it, is what you using to make and break a circuit. In this case the ground signal coming from the thermistor in the fuel tank. This ground with a power on the other side of the Latch coil, will close contact to your bulb circuit. Either power or ground, its just a switch. Set it to do either one.
Can do the same with the transistor, as is just a Micro Switch, electronically controlled. this would make for a very small install or the circuitry.

Wiring the ground side would probably be less rewiring for me. What would I hook up to 30, 85, 86, and 87 if I did the ground side?

Should be just like I posted, 30 & 85 are power, switched by your Key.
87 is power out, when the relay closes, to your low fuel light bulb, with the other side of the bulb grounded.
86 will travel to ground, through the thermistor in your fuel tank, so it will supply the ground when the fuel is low, to Latch the relay. This will turn the light on, when the Thermistor loses contact the relay will open, turning off the low fuel light.

I think I misunderstood something you wrote in the previous post. I thought you meant I could wire it using the ground from the LED to the relay somehow. Like, Would it work to change 87 to the ground from the LED, and 30 to a frame/battery ground? Or would that cause a short/blown fuse?

That's right you can change those two, as that is where the Switch contacts of the relay are. If you do that, then your Bulb will have to have power, maybe that's how it is now since that's how it was, and this switch 30-87 will be ground.