tri z 250 question

[jaybo3333]

i have an 85 tri z 250. it runs but i think it needs to be rejetted or a carb rebuild. the low end is sluggish. the mid is strong and the top end is missing. does anybody have any suggestions on what to do to make this engine run well. the bike is stock and everything i do to the jetting makes a substanial difference, but i can't get the bike dialed in. for example if i change the main it crispens up the top but i lose power in the bottom. somebody please help.

[G-MAN-1]

drop the needle a bit.use the crisper jet though when doing this. try this example first. then work on it.

[jaybo3333]

i dropped the neddle to lean it up and changed pilot from a 45 to a 40. my mid is hitting strong now. the bottom is better but still a little sluggish and the top is better also but still missing. it feels like it's not getting gas to the carb then it hits and then it misses again (at the top). the wierd thing is that when i give the throttle a twist when the bike in in nuetral it runs great bottom, mid and top are all there. when riding it, it starts to act up. i have heard of people changing there fuel pump/petcock to just a regular petcock. does this improve any performance?

[Dynofox]

If you don't think it's getting enough fuel on top end, go up a size on your main jet, that should help.

[YTZ250N]

if it is an 85 try a 470main and turn the air screw one turn out with the needle in the center pos.

[GreenBoy]

Just check if the nozzle is broken.I had this prob twice now on two different Zs.Just a tip......