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MiniMadMan50

Adjusting fuel screw

14 posts in this topic

What that heck do you guys use to adjust your fuel screw? I have about 30 different screw drivers of varying lengths, and the smallest one (you know what those small ones look like) is too big to fit between the carb and the crank case! I just know that if I go down to my Yamaha dealship, it's probably a 30 dollar special order or something :)

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Zip - Ty adjustable screw is a must. Then you use your fingers. Some guys have welded a T handle to their screws. It is easier to use the Zip - Ty since it has 4 positions marked on it. :)

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motoman has a free alternative on his site, uses a piece of automotive brakeline, bent to facilitate easy cranking. works great

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I used a micro eyeglass driver until I received the Zip-Ty. It works but I recommend investing in the Zip-Ty and never worry about it again!

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sorry for a silly question?

wat does adjusting a fuel screw do

besides getting a good idle?

:)

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Adjusting the fuel screw works the 0 - 1/8 throttle opening. It adjusts the air fuel mixture for the very first opening of the throttle. Gets rid of that anoying little flat spot when you give it a twist from full closed.

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I bought the Kouba T handle. He is a great guy to do business with. He sent me the T handles before he received payment.

Kouba

Fryboy

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Take a screwdriver out of one of those small jewellers/watchmakers sets and cut it shorter a bit at a time until you get the length you need, works great and cheap too.

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This is my first post so bare with me. Is there a particular or special procedure for getting the correct setting of the air/fuel ratio, I have just had a zip ty screw installed but I am not sure on how to set it up.

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gday, jonesa03,how are ya?

From what i have heard (i havnt done it yet) the way to set your fuel screw is by starting the bike up and warming it up, then setting a fast idle, with the idle screw. Then start adjusting the fuel screw 1-1.5 turns away from stock in either dirction. the sound of the engine and idle speed will change, you have to adjust it in between the two extremes, when the idle rate is at its fastest and crispess note from the exhaust.

correct me if im wrong guys, this is what i have read.

Hope it helps!

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Gday Brettv,

Thanks for the reply, i will give it a go and let you know if im doing it right, sorry about the delay of the reply, i was away working all week and went on a 2 day ride up to Rockhamton/Yeppoon in central queensland, had a ball, so i will see how you your advise goes.

Thanks Jonesa03

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This is my first post so bare with me. Is there a particular or special procedure for getting the correct setting of the air/fuel ratio, I have just had a zip ty screw installed but I am not sure on how to set it up.

from

http://www.thumperfaq.com/sitemap.htm

find

http://www.thumperfaq.com/jetting.htm

and

http://www.thumperfaq.com/fuel_screw.htm

and

http://www.thumperfaq.com/mxa_thumper_fuel_screw.htm

and

http://www.thumperfaq.com/not_free_carb.htm

also see this article:

http://www.atlanticmx.com/archives/00000135.shtml

jim aka the wrooster

'01 wr250f

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