I just bought a 2007 raptor 700 without researching them much and it is missing the air box lid and the spark arrestor insert. From what I'm reading that will make it run lean. I have no idea how long it's been like that but the quad is pretty clean and doesn't look to have been beat on. It seems to run really good and has no popping or back firing. Is it possible that there is a tuner in it that is mounted hidden away somewhere? What is the possible damage from it running lean? I already plan to buy an air box lid and get another spark arrestor insert (if anyone has one I'll pay shipping). I've never ridden a quad quite this powerful so I don't think I need to do any mods for a while.