I just bought a 250x off some guy on Facebook and I got it, it starts and idles fine but when you give it gas it chokes itself out it seems like and eventually stall if you keep giving it gas(will not rev) we took carb off and gas is getting into the head. A lot of it, we adjusted the carb and no difference same thing keeps happening any help???

 

Might be time to replace the float needle or get a good rebuild kit for less than an oem needle would cost.NEW SHINDY Carburetor Carb Rebuild Kit / HONDA 1986-87' TRX250 TRX-250 / H-00431 | eBay

 

Another thing to try is drain the tank and carb. Replace all the gas with fresh, new plug wouldn't hurt either. A little water in the fuel can create similar symptoms.