Haven't been able to mess with the bike in awhile and now I'm getting back into it.
The bike has had this bog for the longest time and I have fixed some things that contributed to it. Like replacing the leaking diaphragm, new stock jets, and is still bogging at about 1/4-1/2 throttle. Any info may help!
Always a challenge . if you can just crack the choke open a touch and it improves it an indication its lean on the idle jet .if its worse its a tad rich
Sounds like rich bog off idle. What pilot are you running? I have mine set up according to the following link https://www.thumpertalk.com/forums/topic/282432-ttr-250-modslinkspics/. Works flawlessly and has done for over 2000kms with the jet set up described. Plenty of grunt for a little 250, ok fuel economy and no bog or hesitation anywhere