I can get it to start and if I try to build RPMs slowly it will, but if I stab at the gas it just falls off. It won't really idle. I just put in a new plug and fuel filter with no change. Air filter is fresh also. No major mods (K&N with outerwear and no airbox). I did just have a problem with the charging system that progressively got worse. I finally figured it out in late June at the dunes. I thought the battery was just getting old when in fact the rectifier was bad. I had run the battery down to nothing and it wouldn't runanymore. I replaced it and put in a new battery about a month ago but it still isn't running right and I am supposed to go back to the dunes in August.

Help!!!!!

Is there an easy way to diagnose a bad CDI? That is a spendy part to just replace to see what happens. What else could it be?

 

make sure the thumb throttle only have 1/8" play.too tight or loose can make it run crappy......

 

is it a 2-stroke? if it is i would look at the reeds.

 

throttle is good. reeds??? interesting idea. i don't know much about them but wouldn't they make a noise if they were damaged?

 

Also could be dumping fuel if needle and seat worn,AND the other way could be lean from the K&N even with outer prefilter? Jetting?

 

The regulator is the most common part to fail in a Polaris charging system.


operation of the CDI related to the Coil assembly.

Typical set-up.
Inside the basic flywheel rotor are usually two main coils. One coil is fairly large and supplies about fifteen to thirty volts AC to the rectifier for the battery and lights. The other coil is a smaller, more finely wound coil to supply a hundred or so volts to the CDI unit. This charges the capacitor in the CDI (Capacitor Discharge Ignition Unit)
Under the flywheel is a small, finger tip sized pulsar coil, which triggers by interruption the CDI at the correct time, discharging high voltage to the ignition coil for the spark.

There are four or more magnets inside the flywheel (it rotates), such that as they pass the stator (static) coils, they induce a changing north - south - north - south alternating magnetic field in the iron plates of the coils, thereby generating electricity in the copper coils of wire. Some ignitions/alternators have more magnets depending on power output.


Most of the time there is a black wire coming out of the CDI unit that allows the ignition switch, engine switch, ETC to ground out the ignition when applicable. If you disconnect this wire from the CDI you should be able to isolate the kill system. Check again for spark. If you still have no spark and you are sure you have installed the CDI unit and stator correctly then about the only thing you have left outside of checking for broken/disconnected wires is to swap out is the coil itself.

thanks to Lewy and Farmr at the Frontier

 

I guess the description I gave in the beggining was a bit missleading. The charging issue I had taken care of a few weeks ago. It was the rectifier. The problem was that I couldn't get it to run right since then. I thought for sure it was a related problem. As it turns out, it was a whole separate issue. Running with the reed suggestion I pulled off the carb and the boot to look at the reeds which looked fine. But it did feel like a fuel problem more than a electrical one. So, since the carb was in my hand, I took it apart and found a bit of crud in the float bowl. After a thourough cleaning it is running better than it has in a while. I think it was one of those gradual things that you don't notice until it gets bad. And it just coincidentally happened when I was having charging problems too.

The moral of the story is to cover the basics before chasing after the complicated stuff I guess. That's how it usually goes with me.

Thanks for the help all.