I'm going to make it to where I can go up there if I need to I guess. Gonna start out lower first. I'm sure there are dealerships that "might" warranty it if they install them, but I wouldn't go crazy just because they say that. I've ran chips and custom tuned ECM's on my trucks, and I have a buddy that works at a dealership. They will warranty it, but I have to put it back to stock. Only because, anything MAJOR that comes in for something under warranty, someone from GM usually has to come inspect it (like an insurance adjuster) before they will pay the dealership back for the work. If they refuse, I'd bet the dealership would to since they wouldn't get reimbursed for their work. I don't know if ATV dealerships work that way, but thats what they told me at my Truck dealership. If a manufacturer finds out that a dealership has been warrantying work on modified stuff, the dealership could be liable for costs and it could mess up things between the dealership and manufacturer. At least with vehicles I've heard.
And I could be wrong on a lot of that stuff too, so correct me if I am. I just look at it as dealerships will sell trucks off the lot with 6"-8"+ lift kits on them and huge tires and wheels that they put on. Sure, the whole truck is under warranty, but I bet they try like hell to not fix it under warranty if a wheel bearing goes out or something.