First lets look at the basics. Did you check battery Voltage with a Multimeter? and what did it say? Did the head light dim when you hit the start button? Do you hear a Buzzing Sound from by the battery when you push the start butting? No Loose wires?
Here are a couple things to check first.
1. Check over by the Battery, you will see the Starter Relay just to the left of the battery, then you will also see a small white box (it's bout 1 inch by about 2 inches in size) tht white box I just described contains 2 Fuses (One fuse is a Spare) they should be a 15 Amp. Make sure the fuse it is not blown. If it is blow use the spare one. If that is all good then check step 2 below.
2. Find the connector for the Clutch Switch on the handle bars by flowing the wire down, it will go under the "hood" and it will be a Yellow/Green Stripe fire and a Green wire in a black connector. Find a way to jump those together and see if it starts then.
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