I had a similar problem with my 03 it turns out it was corrosion in my fuel tank strainer not letting enough fule thru to the carb. As soon as I cleaned it and then later replaced it, no more issues. You might want to check the prepcock unit in the fuel tank itself.
2003 Rincon: 25" Goodyear Mudrunners, Big Red Gear Reduction, Elka Shocks w/ Remote Reservoirs, Rubicon 3rd Light, Hand & Thumb Warmers, Meier Hand guards. Warn Front Bumper, Montana Jacks Receiver System, Warn 3.0ci w/ Synthetic Rope, HL Front Disk Brakes, Harley Dog A/F Screw, Clipped Carb Spring, Twin PIAA 520 Super White Driving Lights, Vision X 8" Xmitter LED Light Bar, ITP Rims, HL Fender Brackets, Extreme 2" Lift (more like 1 - 1.5" lift"), PRM-ATV Full Length Aluminum Skid Plate & Front Bash Plate, Scary Fast PowerNow Carb Insert, Dual-Battery System