I own two 1989 phazer 485's with the same problem. They run great when cold, but after riding for 20 miles or so, they will lose power, and run rough. They will idle, but will die or bog when the throttle is opened. If I touch the wires coming from the stator, they may straighten out and run right, at least for a while. Sometimes, they straighten out on their own. On one, I found that if I unplug the yellow wire from the stator, which feeds the headlight,it runs like a new sled. I have been fighting this for three years. They don't stay "broke" long enough for a proper diagnosis.
Any suggestions? I am sure this is electrical, but not sure if its a stator, or the headlight system.

I think you know you have to pull the motor out and check all the wires! I just did it to my 91, it's not too bad of a job.

I think you know you have to pull the motor out and check all the wires! I just did it to my 91, it's not too bad of a job.[/b]

I did a motor swap on one sled last year. Both engines did the same. Did you find your problem? This seems to be a common problem with phazers. I know other people having the same trouble.
You said to check all the wires. Do you mean the harness, or the stator?

I mean, check ALL of the wires, harness, stator, wherever there is a wire, make sure it's good. I found that a mouse had gotten at some wires under the motor on mine.

More than likely just a simple wiring problem. Worst case scenario, you have to find new wiring harnesses.

Check under the hood at night. Look for spark/arcing at a wire connector. That's where your answer lies.

Good luck