I took my 06 yfz450 for a short little daily ride the other day down a trail by my house, it wasent even 15 minutes of riding then headed back to the house down the road in 4th gear and it shut off. Hit the start button and all it did was click. I let it sit a minute and tryed it again..it clicked,clicked,then started to turn as in if the battery was really low with a sluggish sound then caught and fired up. It ran for about a minute then cut back off. I can hit the start over and over and it just clicks, but once in a blue moon it will fire up and run fine for about 20 seconds then will just shut off. I took the little gear/flywheel lookin deal off thats by the starter and hit the start and the starter spins strong everytime. It does have a pro armor kill switch, and when i pull that cable thats suppose to kill it, the starter will still spin when i have that flywheel/gear off.I'm not sure if its supposed to do that or not. This atv has been flawless since i have owned it. Its driving me crazy that it might be something simple, i cant stand not riding it. Any help will be a great help! Thanks again! Chase  

The killswitch is fine, when you have the tether pulled out of the killswitch, it grounds the power @ the coil. not @ the starter. So that piece is fine.

To me it sounds like your coil isn't charging your battery back up. That click click click you are hearing I'm guessing is the starter trying to engage, but not enough power to turn over the motor.

-Randy
www.raptorsource.com  

I've tried jumping it off and it still just clicks, and i trickle charged the battery for about 5 hours and still clicks. The battery is at 100% right now and still wont turn the motor over. I can roll it around and mess with it for about 15-20 minutes then it will fire up and run for about 15 seconds then it'll shut off. Even if the coil or plug was bad the motor will still turn over like a car would correct?  

i was told that the lower crank bearing could be siezing up..sounds about right too me from what its doing. Is this something that a shop would be best to do?  

I called the local yamaha shop and they said it couldnt be the bearings since the motor does runs quite and smooth with no knocking or ticking.  

I am guessing wiring. Maybe even a bad ground.  

i've been doin my best to find the problem, maybe its something with the wiring. I'm going to go ahead and drop it off to the dealer and see what they can find out...because its something i cant figure out.  

Hey Bandit, my 05 Bruin is doing the same thing. I don't know if you said it or not, but can you start it with the pull rope? Mine will start with the rope, but not electrically. The clicking that I hear is the start relay under the seat. The starter does not make an attempt to turn, I think that one out of many attempts it tried to turn over but did not fire up. I replaced the battery and start relay, but no luck. If you figure something out, please post it. Thanks  

This could be a couple of things. The relay for the starter, the starter itself, or the starter clutch assy. My raptor did something similar and the starter clutch was gone. The starter would spin like a champ, but wouldn't catch the flywheel. Once I replaced the starter clutch and adjusted the valves, it fires 1st turn everytime.Check your stator to make sure it is recharging your battery as well, and check your battery to make sure it is holding a charge. It sounds like you have a combination of issues here.