On your starter, at the starter relay, solenoid to car folks, you have a red/white wire and a blue/white wire. Power comes to the relay on the R/W wire. With key on you should get Full battery power, or at most a few tenths less. Any more and you need to clean connections. The B/W wire runs up to the stt button, when you push the button it grounds the circuit, tripping the relay. The ground path for the button is critical.
Your bike appears to be an 80 something. This late a model the ground path is from button to switch housing, to bars, across the bars to the left side housing where a black wire carries the ground down into the headlight bucket and plugs into the harness ground.
If you have power on the R/W wire unplug the B/W wire and run a jumper from the B/W wire to ground. This should spin the starter. If not the relay may be bad.
If it does spin the starter, trace along the B/W wire looking for broken of unhooked wire. At the right side switch housing you can take the housing off the bars and take the insides out. Clean the Button and the place the button contacts. Clean the other end of the metal strip the button touches, this is where the ground path connects to the bars, clean the bars at this point too.
If the Horn works your ground path from the bars to the harness are ok, The horn works the same as the starter relay, power to horn, pink wire to button, button grounds to bars.
On the color of your beast, it not bad, not a color scheme I might choose but it's eye catching.
On the no spark, If it's an 80 and later bike it came with an electronic ignition from the factory. A Transistor Controlled Ignition, TCI for short.
This system uses a magnet in the stock charging system rotor, a pick up on the stator. The TCI uses the signal from this sensor to determine crank position. IT needs full battery power at the coil as well as at the TCI box mounted under the battery bow, R/W wires. Power goes to the coil same as points, from the coil to the TCI box that grounds and ungrounds the circuit the same as points but uses transistors.
In your manual it should have a section on testing the ignition components. Test the coil as described if out of spec you may need a replacement. There are tests for the pickups too.
The TCI box has no tests listed other than try a known working one. There are some things that go wrong and can be fixed. A search for TCI box fixes should find links to that.
If it does turn out to have a bad box the easy thing is an after market ignition. A bit of searching will lead you to those options as well.
Good luck with your project.
Leo
