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Can someone Tell me if this jetting sounds Ok?

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I have just got a 07 RMZ250 i went into the carb today to clean everything out etc and these are the jets I have found inside. Could someone tell me if they sound ok, the bike seems to run ok, but i know its not stock, and my bike is totally stock. Just looking to see what yall have been running with good luck?

Main: 180

Pilot:45

Slow??? (small little jet next to main jet):75

Leak:40

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my carb is off so i will take a look tomorrow cause I cant remember... But the main seams big..?

the only thing that really matters is how does it run?

Does it bog?

Is it quick to respond to throttle snap?

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Yes has a bog or dies when i do a quick snap off idle. My friend suggested going with a bigger leak jet i.e (55), Would the O-ring mod on the AP help w/ this?

Edited by Paczowski123

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Sorry I wrote down my jets and forgot to post them up, I will try and remember...

I have heard of the o-ring mod but don't know what it is, i'm new to the RMZ family

Have you taken apart your accelerator pump.

It seams like the AP on a lot of friends bikes and my sons CRF250x have been coming apart (see pic below)

I'm not sure if its the additives in the fuel or what. it might be carb cleaner that people have been shooting thru the hole with out removing it.

So, My buddy dropped off his kids bike a few weeks ago(06 crf250x) and had the same problems you describe. I took the carb apart and found this (see pic). It took a bit of effort to clean all the little pieces out of the passages. I put a new stock one in and put it all back together and it ran like a champ

photo-13.jpg

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What surprised me is a bog is actually a lean symptom. Pilot may be a little lean and is the jet that's in control of what you're hearing just off idle throttle snap. You do know that you can make a huge difference there just by adjusting your air screw, right? Matter of fact, the air screw always needs adjusting on a daily basis whether it's just a quarter turn or more. Go tell us how many turns out you are on the air screw, and try screwing it in a quarter turn at a time and see if the bog cleans up, if not you need to go richer on the pilot, especially if you can screw it all the way in and the bike is still running. Make sense? Your main may be a little too rich. Why don't you just get the bike's oem service manual, and check the jetting chart? Then you'll know. It's always better to be too rich than lean. Lean causes motor seizures and burnt pistons, especially on the main and needle, which controls the mid range power (needle) and wide open (main).

We both have keihin carbs, my 98 is

60-70 degrees at sea level

175 main

55 pilot

needle in middle position (3rd clip)

air screw 1.5 - 2 turns out

Edited by BlackCR25098

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Sorry for the delay

08 RMZ250 and this thing rips

Main 162

Pilot 75 (seams big to me but it works)

leak forgot to write it down and now its to late but I think it was a 40 or 45

3rd clip

2 turns out

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A 75 pilot???? Do you mean the slow air jet or the actual pilot?

Also new to these fcr carbs b/c i just came off a 2-stroke, but where is the air screw on these carbs? Is that the same as the fuel screw on the bottom of the carb?

And blackcr98 dont u have a 2-stroke? or are you saying lean does the same on 4T's too?

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A 75 pilot???? Do you mean the slow air jet or the actual pilot?

Also new to these fcr carbs b/c i just came off a 2-stroke, but where is the air screw on these carbs? Is that the same as the fuel screw on the bottom of the carb?

And blackcr98 dont u have a 2-stroke? or are you saying lean does the same on 4T's too?

Yep S.J. I fixed the post tks

See below for screw

Screenshot2012-02-10at82217AM.png

Edited by broccoli2

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A 75 pilot???? Do you mean the slow air jet or the actual pilot?

Also new to these fcr carbs b/c i just came off a 2-stroke, but where is the air screw on these carbs? Is that the same as the fuel screw on the bottom of the carb?

And blackcr98 dont u have a 2-stroke? or are you saying lean does the same on 4T's too?

Crap, I was speaking for 2t but lean on a 4stroke and you will get a popping, and I believe rich is an actual bog...not sure. I have a great video for you to watch though regarding 4t jetting. Now, you need to determine if you have an air screw, or a fuel screw...because they both do similar things but just the opposite of one another because you have to understand an air screw turning it in you are richening the mixture (less air), and turning out your are leaning (more air) AND with a fuel screw when you turn it in you are leaning it out, and when you are turning it out you are actually richening.

Air screw obviously adjust fuel/air mixture through more or less air, and fuel screw less or more fuel...so they are similar, but you have to remember whichever you have they are opposites of one another...

Let me find that video real quick, should held ya a ton especially on Bog vs. popping and what's lean vs. rich and 4t jetting in general!

This is for a CRF but I promise you it's the same carb, same exact principle...

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Ok, well mine has a 45 slow jet, 180 main jet, and a 75 starter jet, and 40 leak jet. I cant beleive yours has a 75 slow jet? Is your bike stock? That seem Super rich?? I mis typed above. I meant are you sure yours is not a 75 starter jet? Even in the video BLACKCR posted it says usually 42, 45, and 48 are usually only used? 48 being for freezing condiditons

Edited by Paczowski123

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