right now i start to bog around 1/2 throttle and up. i have 155m and lowest needle position. i have esr flattrack/tt pipe, no airbox with K&N filter, and biyseen reeds. plugs a little black. and it doesn't idle. please help asap i wanna ride

Lowest needle position? Move it back to the middle. Do another plug check. If your plug is black you're too fat, plus it blubbers on top-end. Is the air screw adjusted right? Turn it in all the way and then back it out 1 7/8 turns. Did that help? Plug still black? Go down one main jet size (from a .155 to a .152). Do another plug check.

i'll try a 152. i had it on the middle till yesterday day then i switched it but i'll try that. what about the idle. i just can't get it to idle. what should the pilot jet be. thanks

A mostly stock, unported, stock carb chould have about a 48 pilot.
Will it idle with the choke on? If so you are too lean and need a larger pilot.
ERIC

nope doesn't idle with choke on, it is diffenently rich but not to bad. i ordered a 52 pilot jet and gonna get a 152 main jet. i'll let you know, but will take anymore ideas

I have been trying to get my R jetted for about 2 weeks now and I think that I am finally close. About your idle question, mine wouldnt idle at all either and all I did was adjust the throttle cable up on the handle bars. This sounds to simple to work but it really does. Try turning the adjuster out so that it puts more tension on the throttle and the engine will rev a bit faster thus it will idle.

Chris.....'87 trx 250r.....too many mods to list