This is not a SFW instance. NSFW communities will be tagged, and efforts will be made to keep SFW communities clean, but proceed at your own comfort level.
Do they have a system of keeping the old tires so if you have a flat and the remaining tire is 50% worn, you can buy a matching tire from someone else who replaced both?
This sounds sensible.
Do they have a system of keeping the old tires so if you have a flat and the remaining tire is 50% worn, you can buy a matching tire from someone else who replaced both?
They typically encourage you to keep the one good one as a spare tyre because you also require a spare at all times to get a warrant of fitness.