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Surge / lope at 3/4 throttle?

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I have a 98 YZ125 that seems to surge /lope at 3/4 throttle and right at the start of the power band coming in. If you just slam the throttle wide open everything is fine and if you start out low RPMs put it at 3/4 throttle it seems fine untill about that point of the actual powerband. Has me pretty puzzled as to why. I had to re set the floats when i got it because the last owner set them so high fuel just flowed out of the carb and had the idle screw all the way in trying to make it idle lol Fixed all that made sure everything was clean inside. Cleaned the air filter again since the last owner thought it was smart to just put what seemed to be gear oil on just the outside filter in lines never even tried to make the oil even out. There was a few other ignorant things he did so i am leaning towards this guy was trying to do something he shouldn't have and he got it dirt cheap to flip it. WOT jetting seems a bit rich when i checked. Iv moved the needle up and down several times but nether seems to stop the surging. To better describe this surging it reminds me of a old V8 with a very wild cam at idle. The bike starts first kick pretty much every time even after sitting for weeks. You don't even have to twist the throttle for it to start lol and without choke on warm days. Idles fine.  Any ideas?

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Took me a while but finally got to checking the power valve. It seems to be working like it should. Any other idea?

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