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You have a flat battery. A little known, but useful indicator, is that if the temperature warning light illuminates when the starter is pressed it means that the cranking voltage has dropped below 9.5V. If you see it, even on a bike that will start, it means you're battery isn't in the greatest shape. 9-10V at the battery while cranking is pretty normal and it will start with anything over 9V. Yours is clearly way below that hence the relay clicking and non-starting. Question is why is your battery dead?

I bet you that the USB socket is the culprit. Most people don't realise when they wire them direct to the battery that they consume anything from 15-40mA even when nothing is plugged into them as the solid state step-down transformer within the unit is working all the time it is connected. It doesn't sound much, but at 40mA it means your battery will be having roughly 1A sucked out of it every 24 hours, and on an typical 8-9Ah battery, that's about 15% of its capacity. The battery will be insufficiently charged to start the bike after as little as two days left idle!

All USB sockets should be wired with an isolating switch, or better still through an ignition switched supply to avoid battery drain.