Electrical prob with atv yamaha warrior when i press the start on the relay switch clicks?

if thats not clickin the solenoid is sometimes if i move the electrical stuff around it will just work but if i ride it for a little bit it wont work again and today it just suddenly worked for no reason and i put a new bat in a couple weeks ago but the wiring and stuff looks pretty coroded the stuff unfroze wen it started workin wat could it be