Hey Guys. I recently purchased my son a Kayo Bull 125. It was in rough shape when I purchased it - it had a transmission grinding issue, and randomly didn’t want to start.

I decided with as cheap as these engines are, I would just replace it and the wiring harness. I got the new one and installed and replaced everything that came with it: wiring harness, cdi, rectifier, start switch assembly, key switch ect.

after getting everything buttoned up, no matter what I did, I could not get the start button to actually crank the atv. It would start and run perfectly by shorting the starter solenoid but nothing would happen from the switch. I have since narrowed it down to the brake safety switch. I have it hooked up correctly and it works the brake lights when it’s running, but if you cut the atv off and turn the switch back on, the lights don’t work and it won’t start from the switch. The second it is running, the brake lights light up and activate from the brake handle. I have checked the wiring quite a few times and checked the fuse but nothing turns them on when the Atv isn’t running. It’s like they aren’t getting power from the batemtery, they are only running off of the stator.

any ideas of what to check? Thanks!

 

"they aren’t getting power from the battery, they are only running off of the stator."

You have probably answered it yourself. Bad or no connection between battery and main pos wire to ignition switch. Has to be before it splits off to the regulator, so about main fuse? Bad earth to frame could do it too. The one to the engine is OK or starter wouldn't work.