01 CR250 Idle problem

[Markus_01CR250R]

Hi guys,

I have an '01 CR250 that absolutely will not idle once warmed & off choke. My son's '00 CR250 Idles steadily all day long. I have been told that the '01's do not have an idle circuit. My factory service manual gives instructions on setting the idle on the '00 model, mentions nothing for the '01.

The '00 idle adjustment works through the choke knob, has no effect on the '01. Local dealership (Yamaha of Troy) tells me that two strokes never idle and shouldn't. I don't buy into this at all.

Any thoughts?

Thanks in advance...

[MATTXR250R]

Yes...it does have an idle adjustment...look on the carb...The black plunger you pull up to en-richen the mixture when cold(CHOKE)and push down to turn off en-richener...turn that black knob COUNTER CLOCKWISE....the engine should start to pickup and idle..might take quite a bit of turning though.

[MATTXR250R]

I didn't read your entire post...you mean the choke knob won't run clockwise and counterclockwise at all?????????:

and the dealer telling you that 2-strokes aren't supposed to idle is BS! My 96 CR250R will idle forever.

[Silver_Fox]

marcus,
I have the same bike and it purrs like a kitty when it idles.
Have you cleaned the carb? or checked for vacuum leaks?

[Mike[socal]]

Did you try backing off the lock nut and turning the idle screw in? The idle screw is the screw with the lock nut in the middle right hand side(if you're standing on the left side of the bike) of the carb close to the inlet. The 01 carb is the Mikuni and does not have the idle adjustment on the choke like the Kehein(sp?).

[Faded]

Mike is right, '01 went to the Mikuni carbs and the idle speed adjustment is the brass phillips head screw (w/8mm locknut) that sits inline with the slide angled toward the ground. If your pilot/airscrew settings are good you should be able to make it idle as much or as little as you want.

[Markus_01CR250R]

No, I have not broken the lock nut loose and adjusted the screw. Didn't realize what the screw was for, didn't want to jsut start wrenching on things without a little bit of knowledge to deal with first, I'll give it a shot.

I haven't cleaned the carb since having it. The bike looks nearly new and was obviously meticulously maintained by the previous owner. However, never hurt a thing to pull the carb off and go through it....good suggestion to start with.

Thanks for all the thoughts guys, I'll give these things a try tonight and let you know how it goes.

[Faded]

Originally posted by Markus_01CR250R
...However, never hurt a thing to pull the carb off and go through it....

While you're there verify/set the float level to 15mm.

[KXforeverdude]

Not all mx 2 strokes do idle. Mine doesn't, and a lot of others don't either. You can make them idle, but it's not stock for all of them.

[motojojo]

My 03 has idled form day one but my friends 03 kx 250 has never idled. I think that every bike comes setuped a little different.

[Silver_Fox]

Originally posted by KXforeverdude
Not all mx 2 strokes do idle. Mine doesn't, and a lot of others don't either. You can make them idle, but it's not stock for all of them.

Sorry kxdude, they are meant to... its just not tuned right. You'll notice if the bike is jetted correctly and all carb adjustments are correct your bike will work better wether it's at idle or full power

[Markus_01CR250R]

So its all better now. I adjusted the Screw on the side and seated the Jam Nut. I assume that this screw is simply raising the slide but I'm not possitive of that. It will idle now until the cows come home or a plug fouls, which ever comes first.

Thanks for the advice guys, just what I needed!

Markus

[Faded]

Originally posted by Markus_01CR250R
I assume that this screw is simply raising the slide but I'm not possitive of that.

You're correct. Good job, glad it works for you! If you're fouling plugs try playing with the airscrew (out=lean, in=rich) until you get the best throttle response (when you wick it wide open it pulls and doesn't bog, if it bogs you're lean). If you get the airscrew set it won't foul plugs. More than 2.5 turns out on the airscrew and it's time to look for a leaner pilot, less than 1 turn out and you'll need to get a richer pilot.

Hope this helps some more.

Later,
Andrew