Riser pads are designed to prevent you from getting wheel bite. Up to a certain point, the use of riser pads is a personal preference, with some people finding it hard to get used to them after having never used them. That being said, as a rough rule of thumb, we would probably recommend using them for wheels size 55/56mm and bigger, and we often see them used on cruiser boards to help provide that perfect turning circle. Risers start at an eighth of an inch and get bigger depending on how big the wheels are. It's worth bearing in mind that you might need to buy longer bolts than 1" if you are looking to buy risers bigger than an eighth of an inch.