Backfiring when under load

[Wilms2004]

Alright... so I got the new air filters and put them in today. There was some oil on the rear filter so it definitely could have been causing a problem. The air filters were actually alot easier than I thought they were going to be. I took some wire ties loose and gently moved the wires around the rear air box out of the way. I removed the boot going from the rear air box to the carburetor and took the screws loose that hold the filter in and then removed the filter. To reinstall I mounted the boot to the rear air filter and put it back in. I then mounted the boot to the carburetor with minimal issue.
In the process of waiting for the air filters I installed new bars on the bike for my wife. The previous owner had rerouted the throttle cable and some wires in order tomake some ape hangers work. I put everything back where it was originally supposed to be to the best of my ability. Afterwards when I started the bike the rpms were pretty high for a few minutes then fell back to normal. At that time I put the bike in gear and began to take it for a rest ride and it died as soon as I applied the throttle. It fires right back up but continues to die when throttle is applied. It also dies out at idle after a few minutes. What do you a think is my issue now?

[Wilms2004]

Udate..... Now I have let it cool and cannot seem to get it started. Just continues to crank

[navigator]

Are both shutoff's / petcocks in the proper position?

[Wilms2004]

Are both shutoff's / petcocks in the proper position?

I wasn't aware that there were 2 shutoffs on the 800s. The petcock is mounted directly on the tank.

[navigator]

Correct, 1 petcock on the 800.
I saw that you owned a 1400, didn't realize you were working on the wifes 800, my bad.

[Wilms2004]

Correct, 1 petcock on the 800.
I saw that you owned a 1400, didn't realize you were working on the wifes 800, my bad.

No worries Navigator.

[Lechy]

The pilot air jets may need cleaning and are often forgotten due to their placement. They can be done without moving the carbs but a catch all under the carb is a must because if you drop one it will be immediately be swallowed up by the Wrencher's Black Hole, never to be seen again.
A Q-Tip with a dab of grease helps pull them out after unscrewing.