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Fuel screw question

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I did a search and couldn't find an answer. I thought I had heard the adjustable fuel screws for KTM were different than other brands for some reason. Want to pick one up form my new to me 07 250SXF but couldn't find an answer to this question. And has anyone tried the r/d screw that comes up on the side so you don't have to reach underneath as much?

http://www.r1dean.com/cart/index.php?main_page=product_info&cPath=1&products_id=48

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Never tried. All Fuel Screws made for the FCR-carb will fit on your KTM though.

OK, just wondering because my friend had an 08XCF and I swear he said the one from his old KXF didn't fit right or something.

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The original FCR carbs (as used on YZF 400s and early KTMs) were just the road race cab with different bells on them. They castings on this carb require that an externally adjustable fuel screw be slightly longer than the one required for the now common FCR-MX carb that is found on all of the four strokes. Some manufacturers still don't make a screw long enough to work on both styles of carb, but most do. Some make a different screw for each so you have to pay attention.

I have an early style FCR on my XR650R. The Sunline screw that I have on my 505 will not fit right on the 650 as it is too short. So if I turn the fuel screw all the way in it bottoms out on the float bowl before the screw itself bottoms out. It was the equivalent of having the screw start at 3 turns out. I could make that work, but I would have to go with a much larger slow air jet to compensate for the overly large fuel screw setting.

The ideal setup is the flex screw from either R&D or the guys who made it first: XR's Only.

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whats the trick of installing one. looks like it is quite a project with the starter where it is.

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The original FCR carbs (as used on YZF 400s and early KTMs) were just the road race cab with different bells on them. They castings on this carb require that an externally adjustable fuel screw be slightly longer than the one required for the now common FCR-MX carb that is found on all of the four strokes. Some manufacturers still don't make a screw long enough to work on both styles of carb, but most do. Some make a different screw for each so you have to pay attention.

I have an early style FCR on my XR650R. The Sunline screw that I have on my 505 will not fit right on the 650 as it is too short. So if I turn the fuel screw all the way in it bottoms out on the float bowl before the screw itself bottoms out. It was the equivalent of having the screw start at 3 turns out. I could make that work, but I would have to go with a much larger slow air jet to compensate for the overly large fuel screw setting.

The ideal setup is the flex screw from either R&D or the guys who made it first: XR's Only.

His bike is an -07 250 SXF so the screw (any manufacturer) will fit just fine.

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whats the trick of installing one. looks like it is quite a project with the starter where it is.

You have to tilt the carb to the right or remove it for installation.

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The carb used from 2000-2002 requires a different screw than all the later ones, same carb change happened on the Jap bikes in 2001

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do you have to pull the sub frame or can you do it without pulling it.

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Just tilt the carb, unscrew the old one and make sure not to lose the washer or the oring.

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