An air suspension fork on one of my bikes starts showing its age: noticeable play, scratches on stanchions etc. It has not become less smooth and does not leak air so far, however.
I am starting to wonder how safe it is to continue using it, and what will happen when it "fails".
Possible outcomes of a non-catastrophic suspension fork failure that I can imagine are:
- All air leaks out and it compresses fully, becoming very short
- All air leaks out and it expands fully, becoming at its full extension
- Air air blows out, making stanchions loose in the legs
- The fork just locks at random compression position.
- Stanchions become so loose with so much play that it becomes noticeable at braking and steering.
What of these options are real, both for air forks and coil forks? Are there other failure scenarios resulting from a fork's old age but not a crash?