To elaborate a little - The hammer and trigger pivot on the hammer and trigger studs which are pressed into the frame on the left side and sit in recessed areas on the side plate. When the side plate is removed the studs are only supported on one side.

A couple cycles of the action probably won't hurt anything but I'd recommend removing tension on the mainspring before cycling the action. Additionally you should remove tension on the mainspring before removing the side plate to reduce stress on the hammer and trigger studs.