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FCR problem.dead spot

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I have a dead spot when I turn the trottle about 1/4"turn slowly. I have swithched to a FCR w/tps and hot start button from a YZ426. I made the

mods suggested by Burned. I did not use the vacuum port nipple as i just switched to a petcock from a yz also.:applause: It seems to be loading up while idling also and I have to remove the air filter to get it started agian. It seems to run just fine when I am on the trottle riding otherwise. Am I sucking air somewhere or is it a jet problem? Also I have a O'ring on my extended fuel screw. Does it go on the end of the screw to hold the spring on or above the spring higher uo on the shoulder.

Thanks for any feed back

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Are you using the same jetting you had in the previous FCR? What pilot jet, what needle and clip position. Running a pipe, othe engine mods?

Fuel screw/spring/washer/o-ring

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dead spot meaning a stall?is this dead spot while riding or in netural?is the engine warmed up?new plug?

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Yes it does stall. It does not seem to be a problem while riding. Only when I am stopped idling or on the stand at home? I cant remember changing any of the air jets.

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2-1/2 turns on the fuel screw. I am not sure what you mean by all the bits on the fuel screw. It is a made by White Bros and I used the stock spring and o'ring. I cant recall if I changed the pilot jet or not. What size do you suggest?

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Yes it does stall. It does not seem to be a problem while riding. Only when I am stopped idling or on the stand at home? I cant remember changing any of the air jets.
if its on the stand or in netural and you blip the throttle it will stall.but if opening the throttle slowly it shouldn't stall and if it is then it sounds like a pj problem .when you blip the throttle on the stand the acc pump squirts raw fuel into the intake and will stall it.

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I have the same carb on m 05 S. I am running the same exact setup. what pilt air jet and how long does the acc pump spray for.

If you have a 38 pilot for need to use a 75 pilot air jet (about 99% sure of this). Also, when I had problems with mine it was beccause the jets were a little gumed up.

Hope this helps.

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Here is a complete list of my set-up

FCR card from 2001 YZ426

2004 "S' model

3x3 mod

EMN needle 3rd clip

160 main fuel jet

38 pilot fuel jet

200 main air jet

100 pilot air jet

2-1/2 turns on fuel screw

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I am almost sure you need a 45 pilot jet. Give it a shot, also check your acc pump. How long does it spray for? Should be about 1 second.

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The acc pump is the accelerator pump.

You just fill the bowl with gas, hook up gas line from tank and put to prime or on, then twist the throttle wide open. There will be a stream of gas the normally goes into the engine. You just count the seconds on how long it squirts for.

BTW - Watch your face, it shoots far...

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