[derding]

It's actually a 91 XC-400 but it's basically the same as the 92 440 XCR. I bought it from a guy I work with who had it for his kids to ride around on and says it always ran great. Anyways the sticker under the hood says the main jets should be 280's. Upon cleaning the carbs I discovered the PTO side is a 350 and the mag side is a 290. Why would this be? Should I change them both to 280's? It's stock as far as I can tell from the clutching.

 

[Polaris_Parts_MN]

A possiblity could be because the PTO crank seal is bad, leaking air, making the PTO cylinder lean, so the previous owner had to put a fatter jet in the PTO carb to make the mixture more rich to balance it out. You can check by spraying carb cleaner on the PTO crank seal during idling, it the motor revs up, the seal is bad.

 

[THE_Norwegian]

i ran 290's in mine when it was totaly stock...