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1986 xr250r carb probs?

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hi all..im new here and i have a question i hope someone can answer...

i picked up an 86 xr250r in pieces,got it together and running.however,once i hit half throttle(load or no load)it wants to sign off.coughing and sputtering.loss of power.

i drained old gas and filled with premium(just this once),took off carb and cleaned every nook and cranny with carb cleaner and compressed air.i even took it out and ran it for an hr or so on the trails just to make sure new gas was in carb.

spark plug is new.someone has removed the baffle from the exhaust.its obnoxiously loud.would this make it run rich?maybe i should lean it out with a jet kit?or perhaps change the clip setting(correct terminology?)

i live in erie pa and am not sure of elevation.real close to sea level i think.

any thoughts and/or comments are appreciated.

thanx,

stic

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when i had the carb apart,i didnt notice any clip.I.E.,3rd setting 2nd setting and so on.can someone enlighten me on where this is and what changing the setting will accomplish?

i believe the carb has stock jets,im just wonderin if i should take them down a notch.just to lean it out a bit.

any thoughts?

oh and...elevation is 650'

thanx

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Removing exhaust restrictions will lean the jetting out rather than make it richer.

While you had the carb apart did you set the float bowl level as well?

What you need to do now is take the carb apart again and read off the jet numbers then post them here. That way we can tell you if the jets are indeed stock or not.

To see the needle clip positions you have to take the top cover off and remove the needle.

As to the baffle, try and get one from an ATC250X, it will quiet it down, but it will still flow pretty well.

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125/40 were the #'s i saw when i had it apart.my manual states those are the stock jets.

the needle jet is the long jet that runs through the carb,correct?i will do this tomorrow and if in fact i can find the clip...what would changing the clip setting do?

theres also a pilot(air/fuel?)adjustment on bottom front of carb.i set this per manual specs but noticed no change.2 1/2 turns from seated lightly seated position.

then manual tells how to adjust things but does not explain why and what diff these adjustments make.

thanx for the input.

more later.....

ps...is that right around the same yr atv for the baffle?

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Ohh you already have a manual. Good for you.

The pilot jet and fuel screw control starting and initial throttle openings. The needle controls the middle throttle openings. The main jet controls 3/4 to full throttle.

A dumb question but you do have a new plug in it right?

Ohh yea and something I forgot to mention before...you should always be running premium gas. The compression ratio is too high for regular gas. Mid grade might be okay, but its not like the bike uses that much gas to make a big deal about it.

Yea I think so. I dont think they made the ATC250X for very long.

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hey...thanx for gettin right back to me.

the manual was the 1st thing i purchased.mamma dint raise no dummy : P

yes,there is a new plug in there.and i just filled the tank with hi octane.

id say 3/4 throttle is where it wants to sign off.that would be the main jet then?if thats the case....i wouldnt need to mess with needle clip,correct?

or....

if its just under 3/4 throttle,would i want to raise or lower needle clip?

what if i just found a baffle and tried reinstalling that.ive been searching and found something that looks like it came from my muffler.

heres a link....

http://www.japmcdismantlers.co.nz/baffles.htm

does this sound like a path i should take?cant seem to find anything else...other than a nice looking stock one on ebay but that guy is asking 100.too much $$$ when theres a new supertrapp for 89.

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If youre not going to buy a baffle go up a main jet size or two and see if it runs better.

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i actually ended up going from a 125 to a 122 main and that fixed my problem.

my guess is that once i hit mid throttle,the carb was being flooded with gas and couldnt handle it.its 99% better but will still cough once at wot.thats something i can deal with just to keep it from running too hot.

thanx to all who helped.

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