1999 ec250 idle

[viper77765]

Hi guy I was having problems with my bike Not running right. It was lumpy with a cough.
I changed pilot from 38 to 42
Main from 170 to 178
Needle from 3rd slot to 1st slot
The bike runs ok it seems now. Much more power however the idle seems really low and cuts out all the time. The idle screw is almost fully in with spring fully compressed but still cuts out.

 

[(F5)]

Like the man said, change the needle all will become apparent.
The std N1EF no chance. We've been here before many times.

Will never idle like a car but once warm will for long enough maybe to open a gate.

20 years old carb may have worn but hopefully not too much..

 

[viper77765]

I'll get a new needle. The needle in is a N1ED.

What needle do you recommend please

 

[RBrider]

Pull the mag cover (left side of engine) and try to move crank up & down. If you detect any play at all, the left side crank bearing is going bad and causing the crank seal to leak. this'll cause a lean condition at idle & just off idle.

My '01 XC 200 ran like yours when i bought it. I went a step larger on the pilot jet and it ran much better. Until the left side crank bearing finished going bad.

Not saying you've got that problem, but it's worth checking out.

RB

 

[viper77765]

Cheers matey I'll check that

 

[(F5)]

Read the jetting database for something close for your older 250 at similar altitude to yours.

 

[Mikeyx]

The needle has nothing to do with idling.

Since you have replaced the pilot jet with a larger one (=richer mix), you should open the screw to make the mix leaner.

 

[(F5)]

That's what the diagrams tell you and correct enough unless the fat part of the needle is too thin compared to the (non replaceable) emulsion tube.

Then large wet droplets come past the needle at closed rather than mainly through the finer pilot cct where it can (im going to use the word loosely) atomize better. Pilot adjustments become less useful as you are getting badly atomized mixture.

Unfortunately the tube can wear oval with age so it is harder to compensate for.