The present invention is a case that holds weight material and is used to add weight to a bicycle. The case is attached to a bicycle frame at various locations via a plurality of attachment straps. The case can be attached to a bicycle frame top tube, down tube or in front of a seat tube. The weight material is removable and can be loaded directly into the case or into one or more removable weight pouches that are inserted into the case. The weight of the case is adjustable by adding or subtracting weight as needed. Weight pouches are segmented to enable the weight amount to be reduced incrementally and to help keep the contents from moving around.

A bicycle simulator includes a base portion having a frame shape; a frame support portion supported by the base portion and supporting a bicycle frame connecting a front wheel of a mounted bicycle to a rear wheel of the mounted bicycle; a first treadmill extending in a running direction of the bicycle, supporting the front wheel of the bicycle, and rotating according to rotation of the front wheel; and a second treadmill extending in the running direction of the bicycle, supporting the rear wheel of the bicycle, and rotating according to rotation of the rear wheel, wherein the frame support portion is disposed between the first treadmill and the second treadmill.