Tao 125 killing battery only while running
 

New stator, new voltage regulator but this thing is killing batteries repetatively.
Only kills them while running and it kills them BAD. As in not savable. It's getting expensive replacing a cheap part but also killing a new battery with ever failed attempt. My daughter can run it for 10 minutes and it fires right back up but when she rides for 30-45 it is stone dead (like .6 volts). I don't know exactly when it dies because it will run without a battery. How can I test a running machine for a battery drain? My tester says it's charging the battery normally. It would seem it it was draining that fast something would burst into flame!

Just thinking out loud here, only, happens while running? Is there a chance someone put a fuse in that has blown with too high of an amp rating? Sounds like you have a short in the wiring harness. Again just my thought…

I'm thinking short in the harness also. May just take it to the man and let them skin me alive...lol Tired of chasing a problem and throwing batteries at it.

Check the voltage at the battery while it's running. You may find that it's too high. If so, your regulator/rectifier is bad...and yes, the new one might still be bad. Or it might not be wired correctly. Even though they plug in, the wires might have to be moved around in the new plug to match the ATV wiring. Look to see if the reg/rec wire colors match the ATV wiring, i.e. red to red, black to black ect.

Check to see which wires are hot after 20 to 30 min. Check to see if it's still charging after 20 min. It can't be showing a charging state and drain the battery at the same time I don't believe. Crank it and ride it without the battery connected until you find the problem. Learn how to do a parasitic draw test if it's draining down while sitting. I wonder if AC volts from the stator can somehow get to the battery and damage it. Just a thought.

FIRST, CHECK VOLTAGE WHILE RUNNING


then read my previous post about charging system