01 ZX rough idle

[sledheadkev]

I have a 01 ZX 800 that idles really rough. Once you get the rpm's up it will run fine. I have pulled the carbs and cleaned them also checked out the reed valves and no problems. Compression was good. Any other thoughts on what I can check? Thanks

 

[khagge]

make sure the tether is on all the way and the little peace of aluminum is inside there i had a similar problem where it wont rev or run right and i replaced the tether

 

[sledr4life]

Choke sticking???? the lever may be down, but the cable may be bad or hung up somehow. look at the left side of the carbs while acuating the lever to make sure it is working.

 

[02SummitX800]

I second the choke hanging up problem. I was out in togwatee a couple weeks ago and mine was idling poorly I noticed the choke wasnt all the way pushed in. I just turned the carb heaters on and rode it around for a few minutes and it fixed itself. Turned the carb heaters back off and away we went.
I have also had a pluged pilot jet before, I thought it was clean had it apart twice, I could see light through it and everything, finnally went and bought new pilot jets, ran like a dream after I put new pilot jets in, also moved up a size and really helped even and smooth out the idle.

 

[sledheadkev]

Thanks for the comments. I have checked the tether (had that problem several times) and also checked the choke cable and choke when I pulled the carbs off. I have determined it is the PTO side by pulling the spark plug wires when idling.
The motor shuts down when I pull the mag side. Im wondering about fuel mapping but figured that would effect both cylinders? Thoughts?

 

[sledr4life]

that leaves alot to guess at

Bad sparkplug, plug wire worn through and arcing to the motor, bad plug cap.

I would start with those then onto the coil, stator, check all the plugs on the mpem.

 

[02SummitX800]

That is exacly what mine would do when the pilot jet was plugged. You could pull off the pto plug and the sled would continue to run the same way, you pull off the mag plug and the sled would die. In my case I then checked the spark in the pto side and it was just fine. From there I determined it was the pilot jet.
I promise you that if you check your plugs and both of them are sparking as they should (go the harbor freight and by a spark plug wire tester for $5, it plugs into the spark plug wire and then the other end plugs into the spark plug, lights up when there is spark), then put in new pilot jets and it will run perfect. Get 20 pilot jets instead of the 17.5, it will idle more consistant and wont have the hanging idle problem that these sleds sometimes have.

 

[sledr4life]

in your orginal post you say you pulled the carbs and cleaned.

Did you check the pilot jets?

 

[sledheadkev]

Yeah I pulled them apart and cleaned and blew out the jets. I'm going to try putting the bigger jets in and see if it works.

 

[eddy]

pilot jets

We just replace pilot jets because they are almost impossible to clean and they are relatively cheap.

 

[MtnRidr4Life]

What my family has found easiest for cleaning the pilots is to take a steel wire brush with the 1" wires and clip one off to clean all the crap out in the center and the little holes. Then blow it out with the air compressor and it's as good as new.

 

[sledr4life]

X2 with mtnrider.

IMO it is impossible to blow out a pilot jet without using a torch cleaner or a small wire as he stated. They actuall get plugged to the point that carb cleaner and air will not work alone.

I would guess you dont need larger jets.

You could replace them if you dont have a way to clean them.

 

[sledheadkev]

Thanks for all the help! I took the air hose and carb cleaner and a stitching needle to the pilot jet and was able to get it cleaned out. Idles fine now.
Thanks again.