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Starting to get VERY frustrated with FCR carb

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Ok, I bought a used FCR that is from an E model, 2003 I believe.

I got it and it looked to be in great condition. Jetted per Eddies instructions.

When I initally installed it the bike ran and performed great. Only a slight sticking of the throttle off idle (more on that later as it seems unrelated to current problem).

The problem that I am having now is a hanging high revs after throttle application. The higher you take the throttle up the higher the revs hang. This happens even with the throttle rolled shut.

It is to the point of being dangerous and a couple times I thought I was gonna have to hit the kill switch.

Yesterday I took the carb back out and can find no detectable reason that the slide might be hanging. It moves freely and all the wheels look to be good and rotating. I can see no wear on the carb body.

Linkage feels good off the bike. Fixed the sticking off idle when I noticed that the inner throttle wheel was bent a little and not contacting the idle screw top but going down the sides of the idle screw until it hit the threads.

The high revs are still there even if the throttle is snapped shut. The engine just slowly winds down on it's own after like 5 seconds.

Some things to note, I didn't think this started happening until I took off the coast enrichener and did the bypass trick instead of nipple caps so no jetting changes. Today I put the CE system back on only to find out the problem is still there.

I am getting close to my witts end and close to putting my Mikuni back on so I can at least ride it.

Anybody have any ideas that could help me? Could this be a plugged jet somewhere?

:applause::eek::lol: :lol:

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sounds like your sucking air in where its not supost to be sucking in.check the all conections

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Try a bigger pilot jet, just a thought, I've seen the idle hang from too lean of a pilot jet. Seems mechanical if the idle was hanging from a bent part as you described. Good Luck, don't get too pissed, you'll figure it out.:applause: vanram

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Provided the throttle slide is correctly assembled, and the cables or adjusted, a hanging idle is caused 97% of the time by a lean pilot jet/fuel screw setting.

The other 3% would be an air leak.

What pilot jet do you have, and what altitude do you ride at ?

Have you confirmed correct fuel screw adjustment and pilot jet size, using Eddie's instructions in the jetting forum.

Link here.

Neil. :applause::eek::lol:

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i know nothing having said that is it snapping shut once installed(without running bike)maybe you have to much tension on one of the cables it should snap shut everytime you flick it i know i put to much tension on mine one time and it used to creep back slowly (sounds a bit like what you are saying when you rev it hard it takes longer to slide back at least thats how i read your post)

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This is the jetting.

as per eddies instructions.

the quick set up for that carb is as follows-

165 main jet (stock is 142)

dxp needle (stock)

clip 5 (stock 4)

48 pilot jet (stock 45)

2 turns fuel screw

Bike starts and idles great.

I am gonna go out right now and unhook the cables quick just so I can stop second guessing myself. To rule that out anyways once again lol.

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Update fellas

Just ran it with the cables completely unhooked at the carb.

THrottle wheel is free to turn and feels good. As soon as I start it it is hard as hell to turn. It will break free and then rev way up and hang. I tried this several times and it is very hard to turn. Seems I can put all the pressure I can to close it and it is still revving.

Turn the bike OFF and the throttle wheel turns free and normal.

Start it back up and can barely turn the damn thing.

Turn it off and free.

Now I am stumped.

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make sure the slide plate is square end down.

Well poop, I have not touched that but I can check it. Might have to take the tank off for the 20th time lol.

I assume eddie you are speaking front to rear and not upside down?

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Eddie

Would this upside down slide plate make symptoms like I posted in post #8 of this thread?

Also what exactly is the slide plate?

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Is there something that holds the clip in place that is on the needle? If so, it may not be present and the needle is not shutting all the way with the slide.

I'm not familiar with this particular carburetor but there are zillions of motorcycle carburetors that operate this way. Make sure the needle is secure to the slide.

Dale

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Another tidbit of info.

I had the TPS loose to remove the CE the first time. It has sloppy holes and I paid no attention to where it was or where it got tightened too because I have been told a 1k times that the TPS does nothing on these bikes.

This is correct right?

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Also what exactly is the slide plate?

Yes it will give the same symptoms as a lean pilot mixture, hanging idle.

The slide plate is item 19 in this picture.

Neil. :applause::eek::lol:

There is a much better pic at Sudco, click on carb diagrams, and then FCR sidedraft.

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so just for clairfcation(for me being a nub)i am having some of the same syptoms i have a nex fcr mx so you guys are all saying that when carb is in bike the flat end of slide should be facing down correct????

just trying to figure this out so when i pull carb off next week to adjust extended fuel screw i can check

also would bike run hard and pull all the way through throttle if slide was upside down(only issue i have is running a bit lean on idle and a lot of popping)

\

sry changed this post a few times

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