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Noob jetting questions xr250

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I want to pull the snorkle on the airbox and pull the baffle from the exhast to open my 03 xr250r up. I know I will need to rejet to increase the fuel flow so match the new air flow.

From what I've read here in the forums, seems that my Keihin carb comes stock with a 122 main and 45 pilot jets (?) (California model) and that I will need to bump up to about a 135 main.

Am I on the right track? Which jet(s) do I need to get from the TT store for my carb? In the Keihin section it shows round jets and hex jets...I'm sort of lost! :applause:

I think I may want to get a couple different size mains (125, 130, 135) since I ride at several different areas varying from 1,000 to 8,000 feet.

What are the suggestions from the pros :ride:

Apologies for my noob question but I just got my bike last week and this is the first off-road bike!!!

THANKS!! :thumbsup:

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I recently aquired a 04 XR250R. The bike has relativly low hours(about 60). I instantly took note of two things, it has been poorly maintained (i.e. the oil needed changing, probably never changed). The second is it ran lean. It is the California version, thus it had a 122 main. So i changed that to a 132, as that is the spec for the other 49 states.

With these changes, it still runs a bit weird but better. It definatly hesitates when given moderate to large amounts of throttle.

Any jetting suggestions would be greatly appreciated.

Maybe it needs a larger pilot?????

Needle possistion change?????

Thanks in advance

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I run a 135 Main and a 48 Pilot. The larger pilot helps with starting makes it much easier. If you pull the snorkel on the air box you will also need to do something to the exhaust. If your exhaust has the removable baffle or insert take it out, if not do the Gordon model described in another thread with pictures. (drilling 3 holes in exhaust outlet) I left my needle in the stock position. If you let more air in you have to let more air out. :thumbsup: Get the carburetor # off your carburetor and you can find the right jets in several different places. I purchased mine through a honda dealer for about 4 bucks a piece, or try www.denniskirk.com.

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My 98 had the 132 main, 42 pilot? not really sure about pilot. I went to K&N in 2000, baffle thing had been removed (bought used). Run K&N (no problems with dirt) and went to 135 main. Runs great, stock needle. Probably a jump on the pilot wouldn't hurt as it acts like it needs more gas to start (but can't turn the throttle or it won't start). Usually run idle higher for start, or choke it even when warm. I think the consensus is 135 main for opened up bike, sea level and up a little. I think in MO we are generally less than 1000 ft.

Getting up 4000 - 8000 ft. you will probably need a little smaller, not sure I'd go back to 122 though, that seems small. I don't know much about elevation jetting, but it is probably here some place.

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I just finished gordon moding my 250... new 135 main adn the pilot i left alone... thing started with no choke... which was a bit weird i think.

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