Hi,
my primairy chain has done around 10.000 miles now.
It was always been reasonably oiled and never really overstressed.

How long do these chains last ?
Should I change it ...?

Modern good quality chain on modestly powered machinery running in an oil bath will probably last at least 100,000 miles. Mileage is not the criteria for replacement. See if it pulls away from the sprocket 90 deg from the tangent point. This will indicate wear.

email (option): pvlietstra@gmail.com