Good day,
I知 new to this form, I bought my son a gio atv, not sure of the name because it only has 120cm3 on the side of the engine. It is second hand to me.
it work fine for a while. But not so much now.
I put a new battery on it cuz the old one was toast. But the trouble I知 having is that sometimes the bike will start perfect with the button but other times I got to start it by jump start. Seems more often then not I知 jump starting it now. Any help would be greatly appreciated.

 

Does the solenoid click once when you press the button but the starter fails to spin? If it does, it is probably going to be a faulty solenoid. To be certain, put a 12v test lamp between starter live and earth, if when it fails to start, the lamp lights, you have an intermittent starter fault, if it doesn't light but solenoid clicks, faulty solenoid. If solenoid doesn't click, could still be solenoid but could be anything in the thin wires to solenoid, bad start button, broken wire, faulty lock out. You find out which thin wire has a fault, one should be pos with ignition on and the start button pressed, other should be negative, and trace that wire back to the fault.

 

Sometimes the starter spins and engine turns over, and sometimes the solenoid just clicks. I知 thinking my trouble is either a bad wire off of the solenoid or the solenoid it痴 self. I値l try what you said for test and trace the wires. It seems like this trouble started when my son went through a bit of water one day and the bike cut off on him. This trouble has been happening ever since. But it wasn稚 much water maybe half way up his tires. But The solenoid is just above the back left tire. Thanks for your help.