Bough a 2003 TTR250, whoever tried to service carb before me stripped and pinched off (with pliers) the accelerator pump nozzle jet. You cant buy this part and it doesn't show on the exploded ipc diagram.
I would find an appropriate sized drill & gently work it through to open up the pinched off area. Then smooth out the mangled end with Dremel/rotary tool.
To get an idea of the drill size, try various items like paperclips, thumb tack, etc then measure that. Digital calipers are pretty cheap now a days and are handy to have.
I got the bottom cleared out with a 1/64" needle file, but the nozzle hole is too small, and it's tough going through the body of the carb. Cant even get a sewing needle in.
Looks like I'm going aftermarket, original carbs are going to be $700!