I just bought a 1999 WR400 from a local dealer and about an hour into my first ride the problems started. When I twist the throttle hard from idle the bike just boggs out . It even stalls if I don't let off the throttle in enough time . I set the idle high to temporarily fix it just to get back . Well seeing as how I just bought it I took back to the dealer for them to fix , here's what they have done so far : complete cleaning of the carb , try new factory jets , and inspected the accelerator pump . Still not fixed . I just figured the pilot jet was clogged . Any ideas out there ?