I got my son a polaris predator for Xmas,. I purchased about 2 months ago and had it sitting in my shop so he wouldn't see it. It seemed to run extremely strong and started right up no problems. So I give it to him for Xmas and he wants to ride, but we are in a cold snap of between 0 and 10 degrees f, at sea level. I told him not a good idea until we re jet. This quad has a pure polaris exhaust which I don't know if it is stock or not, and has a k+n filter which I'm guessing is not stock. I checked the main jet and it is a 150. The manual says for 40 and below to run a 155. With it being so cold, should I go up 1 more size? Also should the main jet be increased due to the exhaust and filter?

 

Pure Polaris silencer was after market. Main thing is plug chopping and see what the the plug shows. I'd do that first. Take a high speed run,pull the clutch and kill it.Coast to a stop. Plug should be a tan to medium brown color. If it's whitish in color,jetting needs to be bumped up. You may or may not have to jump up.You may have to play up and down with the needle also to fine tune it.Jets can be bought individual through Jetsrus or they offer different size jets as a kit.https://www.jetsrus.com/a_jet_kit_at..._2003-2007.htm