My 250r jetting help!

[300rman]

hey, this is NightBiker07. my regular account is having issues? talking to admins about it now.

anyway, i got my 250r back together, with a 300r kit, and a 38mm mikuni to feed it.

the bike idles great, and runs good.
when i ease through the throttle, around 1/2 throttle, it bogs/sputters(not sure which) but if i hammer the throttle, it wails straight to the top, with no problems at all. if i go richer on the main jet, it constantly sputters on anything above 1/3 throttle, and smokes like a mosquito fogger. anything leaner, and it runs HOT (around 280 degrees)

the curent MAIN jet lets it run decent everywhere, but as i said, if the throttle is not HAMMERED, it gets a funny bog/sputter at/around half throttle, and WILL NOT come out of it unless you lets it come back to an idle and hammer it. Does not seem to have a plug fouling problem either. in fact, the plug gets a black-ish tint to ONLY the core and electrodes, the rest of the plug stays fairly clean. runs at around 240 degrees, and about 350 on the headpipe right on the jug. (cousins big red headpipe runs in excess of 500 degrees, and cylinder temp hovers around that of mine as well)

also, the thing is a BEAR to start, not because i cant kick it, but i gotta kick it ALOT, and use starting fluid when i get shitfull of kicking it.

i adjusted the needle some, but have not played with it a whole lot. i figured i would get some pointers before messing around too much more.

[jeffatc250r]

I had a mikuni 38 on my 250, had lots of problems trying to tune it in. Buy a keihin, you will be much happier.

[300rman]

well, i have the minuni mounted, and have about 80 dollars worth of main jets invested in getting a good one.

i am not asking for what jets to use, but more or less what i should try to remedy the problem. (like richen needle, richen pilot, lean air screw) a point in the right direction is what i need to figure it out.

with that being said, anyone have any ideas of what to try, with the given symptoms?

[Liquid-Darkness]

Drop your needle all the way into the bowl. Bring it up one setting till there is a slight little drummer in your 1/4ths to 3/4ths throttle. Turn your mix screw out no more then 3 turns or in no more then 1 turn till it idles as high as possible, then reset the idle screw. Your main should be jetted to where you can roll in 1st and stab the throttle with out any hesitation and hit the topend of your powerband. Its how my R is set up and it has some prety good mods on it. Runs great and its ready for any hill shoot or hole shot. Richer then stock on the main and running high octane. Pushing 200psi and 110 Sunoco race gas with castor 927 at 32:1 over here.

[300rman]

cool. yeah, if i hammer the throttle, it hits topend, and it hits HARD, but easing in, it is wierd. i cant tell if its lean or rich.
if i cant straighten it out with the needle, where should i go?

O and i tried leaning it out with the needle, made the problem worse, until it passed 1/2 throttle, then the top end ripped. . richened it back to where it was, but wanted some advice before going further.

[DeePa]

richen up the needle one more time. Lower the clip one more notch, raising the needle up a little more. See how she runs then.

[300rman]

yeah, that was what i was thinking after Liquid's post.

now, about the douchebag-starting?