Update: because of the drawing listed above I was able to locate the circuit breaker. It is under the 4 wheel drive relays and the fuse box. The breaker is in the same cluster of wires as the tail light which is the 3 bullet connectors just before the wires enter the cover under under the rear rack. Unhook them and pull up on the wire easy don't go tearing at it. The circuit breaker is the bag at the end of the 5 wire cluster you just pulled up on. I removed the 4 wheel drive relays (they just slide up and are held in by a rubber cradle i had to wiggle them a little) to give me a better view and more room. The Moose Racing cooling fan draws more power than the Yamaha OEM fan. So I purchased a Marine grade 10 amp type 1 automatic reset circuit breaker, 15 feet of 16 guage wire ( I chose not to color coordinate but do be careful, the breaker will have a side that goes to the battery. It was the red wire on my machine.) I used bullet connectors but flat blade would work too. I chose to relocate the breaker. I put it in the compartment behind the battery where my tool kit was. I drilled 2 holes to bolt the circuit breaker to the side furthest away from the exhaust and one hole slightly larger to run the wire through. I put dielectric grease on the wire before I crimped them and then on the bullet connectors when I plugged them in. I also used heat shrink to seal the bullet connectors. At the breaker I was only able to use the grease but it does have a cover to keep out moisture. Finally, I siliconed the wire holes where I drilled through the plastics. (I had to remove the rear rack and cover to chase the wire. For me it was the best option.) Again, Thank You for posting the diagram.

It sounds like an electronic problem.. If you have a timing light, put that on and watch it flash as the engine stops. If the spark dies before the revs do, then the cdi or ignition coil is failing. If it starts to die out but the spark keeps flashing the timing light right down to the last couple or turns of the motor, then it won't be the ignition.

Maybe headers

Usually a sign of a warped head where compression can leak by and burn/blow out the gasket or the head bolt is not tight or stripped. Secondly it could a bad gasket set your using? Either way it sucks, if you find the head warped and not going to mill it down then just throw two gaskets on it and tighten down in a cris cross pattern to make sure the gasket tightens down properly.