Now that the ring is off the rim the tire can easily come off the rim.
Just lay the tire on a couple of wooden blocks and the rim falls out of the tire.
we discard the old tire and the tube but the tube protector we can use again.
This rubber pace protects the tube
On the left is the old tube right are the new one's these we bought by a local tire centre. With the tubes you have to be sure that the valve-tubing is long enough so you can reach to it after its mounted on the rear axels.
Now that the tire is off the rim you can easily see how the ring has worked
The new tire and tube ready to be installed