Speedometer fuel gauge and accessory wiring
 

Guys, I have looked around for days and cannot find a wiring diagram for a Roketa Predator 150. Or any other 150 buggy with these accessories. Just the usual engine, lights, and MAYBE a horn, but that's it.

I picked up a Roketa project buggy. It has a Yerf engine in it. The previous owner hacked the wiring together, but it worked. HOWEVER, there are cut wires (and missing connectors) for the speedo sensor on the axle and the fuel float sender in the gas tank.

I have tried tracing the wires back from the instrument cluster with no luck. They like to change wire colors at the plastic connectors. And I'm afraid of frying something just because I touched two wires together in hopes of finding the right combo.

If anyone has a wiring diagram, or a Roketa and could trace out these wires for me, I'd be your best friend. Plus you'd be a HUGE savior to anyone else looking. There is NOTHING out there for these accessories.

both the speed sensor and the fuel sending unit are just two different ways to measure current. The speed sensor is a magnetic switch, every time the wheel makes a complete revolution the switch triggers to sends a shot up the wire. That switch needs a power source ,one wire in and a signal wire out to the speedo look at the back of the speedo. there needs to be a ground and a incoming/ signal wire connection. Most speedo's have four wires. A ground wire a hot to battery, a wire to the sensor and a return from sensor. The wires to the sensor would have to be tested with a meter as one will stay continually hot to the sensor while the return would be interrupted with each revolution.
The fuel sending unit is nothing more than a mechanical sliding resistor The float changes the amount of resistance. The gauge is nothing but a amp meter. It reads the volt/amps coming from the sending unit. If you divide the face into 12's instead of full/empty, it would tell you the output voltage of the sending unit This is wired the same as the speedo. A constant hot to the sensor, A return with a fluctuating current. Again you would need to use a meter to find which wire has the fluctuating current by simply moving the float. With the speedo I don't think it makes any difference as to which wire as it is only a momentary on/off that interrupts the current flow. it could make a difference with the fuel as the gauge may read incorrect. As long as you know which wire does what you will be able to figure out the correct connections.