I have a polaris explorer 400 4x4.. I had a problem fouling out plugs once every day of riding if we rode for atleast 3-4hrs... I noticed that my fuel mixture appeared to be rich by the condition of the spark plugs.. I adjusted the needle in the carberator up one notch.. Now it is set to the first positon on the needle.. It has been running great ever since... I have rode it about 4 times.. Is it ok for it to be on the first notch, or is there a chance it may be running too lean of a fuel mixture?? Should I be concerened? It seems to run fine but is there anything going on inside the engine that I dont know about???

 

Shane, Im a little confused about where you have set your needle. If you mean that you have DROPPED you needle to the lowest position, that sounds a little extreme. If I were doing it I'd raise the needle to the center position after I bought a new main jet one size leaner and test it that way. The needle jet affects the mixture from 1/4 to 1/2 throttle & the main works from there to full throttle. It sounds like you are right on the border between the needle & the main. In La where you are it's about sea level & you're main jet should be the stock one. If it is a fatter one go back down to the stock size. Of course a lot depends on what kind of riding you do. If you do a lot of low rpm plunking you may have to drop the needle one more notch from the center.
If you do change the main, test your ride for about a mile at 3/4 to full throttle, turn it off right there, & check your plug. If the center electrode is a nice chocolate color, your main is jetted right on. If it's grey or white, it's too lean, but i don't think it will be.
If you have any more questions, Shane, you can email me if you want & we'll try to help.

Cal

[This message has been edited by hot_shoe_cv (edited 07-23-1999).]