Are bike hooks bad for bikes?
Some may argue that it’s bad to hang a bike by its wheels, because its putting all the weight on a singular point. But based on my experience and thousands of others, it’s just not true that it will do damage. A hook can definitely hold a bicycle up without bending, breaking or damaging it.
Can you hang a bike with hydraulic brakes vertically?
If a bicycle has hydraulic disc brakes (Shimano XT, SRAM Guide or etc) you shouldn’t hang it upside down or vertically. Hanging the bike upside down causes air bubbles inside the reservoir tank or the cables. This can affect the performance of the brakes until the air returns to the top of the reservoir.