Originally Posted by zeeder

Agreed, however, there are parts that are listed as wear items and, as such, are not covered under warranty. These are the things that I consider upgrades and not mods. Things like tires, brake pads, clutch plate and the like. You can replace the wear item with a higher or lower quality part but unless you change the system that uses the wear item it's an upgrade and not a mod. For instance, if you install better brake pads => upgrade but if you install a BBK => mod.