02 cr250 needle valve S-8

I'm having difficulty dialing in my cr250.  It is running rich across the board.  I am running 30 SJ and 380 MJ.  I have the needle clip on the top most position to lean it out but no luck. It is idling ok but it spits and sputter from 1/8 to pretty much full throttle.  Once I have it wide open for a couple of seconds it cleans out and rips. It is also pushing out more smoke at all rpms than it probably should. I am riding alot of woods so I need it to run well down low as well as wide open.

 

I have been reading through some forums and it seems to be a common problem with the 02 carb.  I am thinking of grabbing an S-8 needle valve to try and lean it up.  Anyone have any luck doing this?

 

I don't have the money to buy the PWK carb so i'm stuck with jetting solutions.

 

Thanks in advance for any advice

What altitudes you running at?

 

Id recommend a 380 MJ, and a 32 SJ, needle in the 3rd positions, and my air screw is 1 1/4 out.  Thats what im running on my 02 and it runs great.  We are pretty close region wise so I hope this can help

What altitudes you running at?

 

Id recommend a 380 MJ, and a 32 SJ, needle in the 3rd positions, and my air screw is 1 1/4 out.  Thats what im running on my 02 and it runs great.  We are pretty close region wise so I hope this can help

If he's already running rich these specs are richer than what he posted.

 

Try the s8 if your running the needle in the first clip position.   Then start over in the 3rd clip & go from there.

I have a JD kit with his needles & s4 nozzle for the mikuni tmx send me a pm if your interested.    

Thanks guys, I found the problem this morning.  The carb had a moose rebuild kit installed in it and evidently the needle is not the same size as the stock one.  I re-installed the the stock needle and after some experimenting ended up with it in the first clip position.  After some fine tuning with the idle and air screw it is running perfect in all rpm ranges.  Man i'm going to love this thing. 

 

I

Im using pro circuits jetting specs which include an s 8 nozzle. Works pretty good for MX. 

they always run the best right before they seize. LOL

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