I bought a 2002 400ex a few weeks ago and it will idle fine and as long as you don’t lay into the throttle too hard then you can shift through all the gears. When I hammer the throttle I can make it to about 2nd gear and then it cuts out and dies, it also has a little difficulty starting back up after it dies but once it does start then I can kill it and start it right back up no problem. I just put a new Dynopro jet kit in it and cleaned the carb. Top end also looks good as well. Any ideas on solutions?