Timing chain endurance

[Perez Oscar <PerezO@domain.elided>]

Hopefully not a silly question- but here goes:

My Spider has 58K on it-- How worried should I be about changing the timing
chain?  Also, when I do change the timing chain, should I replace the Upper
AND the lower or just the upper?  Finally, How common are timing chain
failures?  I certainly don't mind the expense of replacing for the peace of
mind.  I appreciate any advise.  TIA

Oscar

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