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FCR-MX Performance is better but not...

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what I expected. I just finished the install. I fired it up and let it get warm. If I crack the throttle open from idle in neutral it would kill the engine. I turned up the idle and opened the fuel screw a hair and that issue was corrected.

I went for a 5 mile ride. I have smooth throttle response, no surges, no bogs, no problems hammering through the gears, and no problems when just on the throttle steady going at a moderate pace. It seems to run very well with slight decel pop. Idle is fine.

I did notice a performance improvement over the stock carb, but I DID NOT get that, "WOW"! "HOLY S**T"! "THIS IS FAST"! feeling.

Was I just expecting too much??

The choke knob needs to be held open or it will close on it's own, is this normal for this carb?

My set up: 2006 DRZ400SM

Yoshi RS-3 full system, (no Cork)

K&N filter

Stock motor

FCR-MX; 160 main

200 main air jet

EMN needle,clip third from top

45 pilot

100 pilot air

Fuel screw 2 1/4 out

400 ft elevation

80 degrees / 85% humidity.

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The diff is absolutely, and noticeably better. Maybe some of the Holy S**t stuff is exaggeration. Especially compared to a properly jetted stocker with the rest of the mods you have. But she should pull stronger,quicker,and hit the rev limiter before you think

Oh, choke should stay out til you put it back in. Does the petcock get in it's way? Mines super close.

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I messed with the fuel screw and the idle and it seems a little better. At 2 1/2 turns out it does not want to run smooth at idle and at 2 turns out it has a lot of decel pop. I split the diff. and 2 1/4 seems good. ( i listed 2 1/4 in my opening post, but it was only at 2 out).

The bog I mentioned was at idle in neutral (no load). It seems fine when in gear pulling out (under load). I guess this is normal?

Did you put the Boysen Quickshot on the MX version. I remember reading that it would not help the MX for some reason? Mentioned by Eddie.

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I just did a search, Eddie said that the Accelerator pump can be adjusted on the MX version to have the same affect as the quickshot cover. How is this adjustment done?

And is it necessary to get rid of the bog if it only occurs in neutral?

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Zcop,

I thought my choke had to be held open too, but I just had not pulled it out far enough. When ulled out all the way, it stays in place.

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The adjustment screw for the accelerator pump is inside the plastic throttle drum cover.

Not sure which way to turn it, as I have not really looked at it yet.

If you get stuck ask me tomorrow, far to much wine this evening :ride::applause:

If it rides OK do not worry about the bog in neutral, lots of bikes do that.

Neil. :thumbsup::applause::applause:

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Zerbitini, That was it, I wasn't pulling it out the whole way!

Neil, It's one of the screws near where the throttle cables connect? Under the plastic cover that I threw away? Thanks!! I'll also be feeling good in a few hours. Vodka and Red Bull! Great combo, sounds bad, but goes down good!!

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Neil, It's one of the screws near where the throttle cables connect? Under the plastic cover that I threw away?

Yes, mine is locked with some green paint and a spring, looks as if you screw it in for more fuel.

Neil.

:thumbsup::ride::applause:

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So, that "taffy mod" that I read about is not intended for the FCR-MX? Or is that what the screw does?

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Zcop - I feel the same way about my FCR. The throttle response and low end snap rocks, but the top end pull doesn't seem to be what I thought it would be. I'm running the OEM FCR, so it still has the stock needle (DXP), i will be switching to the EMN here tonight, so We'll see how it goes with it jetted for sea level and with the 160MJ. Maybe that will help out the top end pull?

Just kidding, I will be switching the needle out tomorrow night, as my parts its not here yet. :thumbsup: Stupid Stealerships. I should never order parts from them.

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Zcop - I feel the same way about my FCR. The throttle response and low end snap rocks, but the top end pull doesn't seem to be what I thought it would be. I'm running the OEM FCR, so it still has the stock needle (DXP), i will be switching to the EMN here tonight, so We'll see how it goes with it jetted for sea level and with the 160MJ. Maybe that will help out the top end pull?

Just kidding, I will be switching the needle out tomorrow night, as my parts its not here yet. :thumbsup: Stupid Stealerships. I should never order parts from them.

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Sorry about the repeat questions, but I am a bit confused, due to all of the searches and threads I have read.

1. is the "taffy mod" necessary for the FCR-MX or is squirt time good from stock?

2.Turning that screw near the throttle pully on the MX. (adjusting the accelerator pump) Is that adjusting the squirt time, or does that do something else?

I'm a beginner on 4 stroke carbs, so sorry again if I seem to be asking redundant questions?

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1. is the "taffy mod" necessary for the FCR-MX or is squirt time good from stock?

2.Turning that screw near the throttle pully on the MX. (adjusting the accelerator pump) Is that adjusting the squirt time, or does that do something else?

I'm a beginner on 4 stroke carbs, so sorry again if I seem to be asking redundant questions?

1/ Not needed on the MX, squirt time should be in the ball park straight out the box.

2/ Yes is adjusts the amount of fuel squirted.

Neil.

:thumbsup::ride::applause:

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Zcop - if there is no bog off the bottom anymore, then your "squirt" duration from your AC pump sounds fine. What is the actual power issue then?

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