2005 KX 144 power loss/bog issue

Hey guys, wondering if anyone has some insight for me. I have an 05 KX 125 with an Athena 144 on it. Lectron carb, boyeson rad valve, PC pipe etc etc. have been running this set up for 3 seasons with zero issues and awesome power all the time. The past few weeks it has just felt sluggish. I should add I replaced the top end this spring and it ran great all year, as it always has, up until the last few rides. I am losing power around 1/2-3/4 throttle and then once the rpms are really up it runs awesome with great power. I also have had a few instances in deeper sand corners and really under a load where it would bog out almost to the point of the motor dying. And then I would have to clutch it to get out of the corner. Nothing has been changed with the bike for this sudden issue to start. It’s slightly colder this time of year yes, but it’s no different than previous years with no issues. The power valve was cleaned and the spring in the head replaced when the top end was done. I however did not do anything on the bottom end of the power valve near the lower gear. I pulled the reeds out and all the pedals looked great and seem to have good holding power. I haven’t touched the carb because this is my 3rd year with the same settings. I have read about certain electrical issues possibly causing something like this. I have tried unplugging my kill switch with no luck also. Any advice would be helpful. It happened just like someone flipped a switch. I rode on a Saturday and everything was fine and the very next day I rode again and towards the end of the day the power loss issues started. thanks

Josh