foreman bounceing off rev limiter

[cherokee99]

i have a foreman 450, hmf utility pipe, uni fiter, snorkel and am running a #50 slow jet (stock is #45). the story is it was running just fine, but i never jetted the carb after i put the pipe on. i would run fine with good low end, mid range, but not alot of top end. that and i would get backfire on decelleration, (running lean) so i jetted it with a dyno jet kit. stock size dj # is 122, so i ran a 128. didnt work just flooded it out. now i went down to a 126 main. runs better. not flooding anymore. moved the clip on needle down 1 below stock, (and i had NO midrange at all) so now i moved it back to stock setting, 3rd from bottom. i moved the clip back last nite, but havent had a chance to see if it made a diffirence.

FYI, in neutral it will bounce off the rev limiter at a little less then 3/4 thlottle.

but now i have a problem that my midrange is poopy (to say the least). im good a 1/8 throttle(low end), but much past 1/4 throttle bogs terribally. the only way to get out of it is to feather the throttle until it picks up rpms. my 5th gear has NO power. so what do i do now?

any help would be apreciated!!!