500xcsp running poorly
Hello, new to the forum, joined because I have an ongoing problem with my 2000 45th anniversary 500xcsp. It starts great but seems to load up while idling and sputters/bogs with an occasional backfire when taking off. If I take off from a stop and pin it, once it clears out it will take off great and run wide open but if I am running midrange, partial throttle and pin it, it is very slow to open up or it will not open up at all. When running wide open it will sometimes also lose rpms and stay around 7000.
Symptoms seem to be worse the longer it is ridden, if shut off for a bit along the trail, and started back up it seems to run better for a while.
Things I have done:
clutching: 10-54 weights blue/silver primary spring, secondary: r8 helix, sliver/blue spring in #2
compression: 110 both holes
carbs cleaned multiple times, needles at #2 clip (runs worse in #3), main jet: 410, While up north last weekend I tweaked the fuel screws some to about 2 turns out and it ran much better for the day but the next day ran worse again.
TPS is at 3.9 volts
It is not getting very good fuel or oil economy.
Gearing is stock
I am getting some fuel in the airbox, not sure if its more than normal or not
Sorry for the long post, getting extremely frustrated at everything I've done with no success. Thanks for the help