How do I remove a racing helmet from a garbage can?
If the helmet were jammed head-down, you can use a needle-nose pliers to grasp the edge of the tube in the inside of the racing helmet, as shown, and then pull them apart. You may need to twist them apart as you pull.



In your case, since the helmet is jammed head-up, you need a way to push it out from the bottom. I suggest drilling a small hole through the tube recess in the bottom of the trash can. Unless you are intending to hold liquid in the trash can, there will be no functional impact whatsoever. The aesthetic impact is also minimal. I used a simple 3/32 wood drill bit I found in my garage. After drilling the hole, just push the drill bit through, and it should dislodge the helmet with minimal scratching. You can also pull the drill out and try pushing with another thin object. A wood skewer, for example, would be sufficiently rigid and less likely to scratch the helmet.