Yo-yo strings are disposable, and you should change them often if you play with your yo-yo much.

When is it time to change your string? When is starts to get dirty or nasty, frayed, or it looks much thinner than when it was new.

Don’t forget, a new string is cheaper than a new yo-yo, and WAY cheaper than paying for whatever you might break with a free-flying yo-yo after your old, nasty string snapped.