[The Hobbit]

My fuel screw seems loose when I have it out about 2 turns, WTF???
I got the white bros. screw with the bike along with an "R" stock exhaust. Do I want it on the bike or will my bike run too rich with it??

[JAWS]

Did you lose the spring an o-ring?

Joe

[The Hobbit]

Spring??? o-ring???

[Monkeywrench]

Yup.. there's a chance you lost them (o-ring and washer)... They mount onto the fuel screw after the spring goes on. First the spring, then the washer (very small washer) then the o-ring. The setup helps the fuel screw resist turning so easily.
Your fuel screw might also seem loose if you or the previous owner have tightened the screw to its fully 'closed' position one time too many. That compresses the spring, although it shouldn't be a permanant 'damage'. But that o-ring and tiny washer are very important.

On your exhaust -- I'd sure run with the 'R' exhaust, as long as you don't mind taking the steps to rejet so your fuel/air mix matches your setup. But she'd be running leaner, not richer, if you went to the R exhaust and kept your jetting set at stock, since it would allow the engine to exhale more freely than the stock X exhaust.

Good luck.
Sudco.com has the fuel screw o-ring, washer, and spring available if you should need to replace them.
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[The Hobbit]

I don't believe it came with a washer or spring...is the spring part of the carburetor or the kit? I have a 2005 CRF 250x. I don't know how it is jetted or set up. I noticed you had a list of settings; is that what I need if I use the 'R' exhaust?

[Monkeywrench]

Pretty much any time you make a change to the way the bike breathes you would need to change the jetting. This is because you're changing the airflow going out of (and coming into, if you cut the top of the airbox) the engine.

Let's say you're painting your house, and you are mixing up a custom color of your own which uses yellow and white. You tweak the color to where you want it, maybe noting down how much of each color you used to arrive at your favorite color. But if you all the sudden spill more white into your pail ("air"), you need to add more yellow ("fuel") to bring the mix back to where it should be. What tells you when you're properly jetted (meaning, when the fuel-to-air mix is set properly)? Checking your spark plug for one... but if you're not up for quite that much trial and error, you can purchase the JD jettink kit and use his recommendations (chart included) and get it on the 1st try with the setup you have (R exhaust), but you'd need to open up the airbox and remove the backfire screen on the air filter for the kit and JD's jetting recommendations to work properly.

[The Hobbit]

O.k., JD jetting kit as per his recommendations,air box is opened,will remove screen,'R' exhaust is on....
Or do I put the stock exhaust on and leave it all stock??? I have the Boysen Quick shot on but I still get a bit of bog off the bottom.

[Monkeywrench]

Mmm, I'm a little confused. Post back your current setup as it is now.

Pilot jet size:
Main jet size:
Needle clip position:
How "open" is the airbox:
Your elevation/altitude (affects jetting):
Stock muffler?
Stock headpipe?
Removed backfire screen from air filter yet?


this will help.
-matt

[Asmith]

O.k., JD jetting kit as per his recommendations,air box is opened,will remove screen,'R' exhaust is on....
Or do I put the stock exhaust on and leave it all stock??? I have the Boysen Quick shot on but I still get a bit of bog off the bottom.

The R exhaust should work well once you re jet.

You will probably be at a 162 main jet, Red needle 5th clip and the fuel screw at 2 turns out.

I would also change the Pilot jet out to a 42. Get that from Honda Dealer $ 7.00.

Don't worry about chasing the bog until you get the JD Kit installed. Once that's in and running right we'll work thru your bog issues.

When you get the JD kit, you'll notice the two O-rings in a bag. Hang onto those because we'll need them to get rid of the bog...

[The Hobbit]

O.K. Stock set-up (meaning however it comes stock) I have not changed anything in the carb yet!
Except the fuel screw, which I think is missing a spring and or o-ring. the air box has been, Before I got it. Open at the top under the seat. I have a stock exhaust, But just recently put the 'R' exhaust on it to try it out (to lose the bog???).

[The Hobbit]

Thanks Smitty, I'll order JD soon and get back to you when it is in!

[The Hobbit]

OOPS, the other thing I should keep in thought is... Is it legal to run an 'R' exhaust pipe on a street legal bike???

[Asmith]

OOPS, the other thing I should keep in thought is... Is it legal to run an 'R' exhaust pipe on a street legal bike???

Hard for me to answer, the 250X isn't street legal in Cali...

[Monkeywrench]

Ahha -- that may be making your bog worse.

A common tendency to chase the bog is to start changing parts. (Thinking something like this: well surely the R model doesn't bog... let's put that exhaust on, and see what she does. Plus, the R has a much more 'open' airbox -- let's open up the airbox and give it some more air -- maybe that will cure the bog).

The X is too lean for it's own good in its stock form, before even changing to another exhaust, or opening the airbox and removing the backfire screen, all of which will make it run even leaner.

You wait and see - once she's set up right you'll be very happy with the power.

[The Hobbit]

I got It street legal out of state. I'll leave the R exhaust if it's legal if not I'll jet to the stock exhaust.