I think the norm will be once a year for preventitive maintenence. Nothing like having your string give at full draw on a deer. But it really depends on how much you shoot, what kind of string and harness you have, and how well you take care of it. I know some guys that have went over four years with the same string and never had a problem. I have talked to others that shoot competitively that change it after every shoot. Two years is most likely not that big of a deal if the string still looks good, but I might look into doing something with it.

I am sure Len or someone that runs a shop could give a better estimate though.

Paul