I have a 1984 Trek 610 that I've had since new. Other than the wheels and the saddle, it's all original and in very good shape. While the headset feels fine, it's one of those Stronglight ones that has some plastic in it. I'm wondering if I should replace it as a matter of age, as it's approaching its 28th birthday. I should add that I'm neither particularly strong or heavy and don't wear bikes out very quickly.