My understanding is that you do the pair of sprockets and chain together on a bike, but I'm not a biker by any means.
What I would concede is that on a bike you probably have considerably more wear on the chain and sprockets due to the nature of their purpose compared with driving one cam off the other, but then again you replace a bike's chain far more regularly than every 100k miles.
I've replaced cams twice, first time on my S2 coupe which had missing teeth so was a no-brainer (sorry; I don't recall the mileage that car had on it) and second time on my cab which had about 143k on it at the time. In that case the case hardening was showing signs of failing on the cams so I elected to replace them rather than try to get some more miles out of them (on the advice of my indie - who is a biker).
What I would concede is that on a bike you probably have considerably more wear on the chain and sprockets due to the nature of their purpose compared with driving one cam off the other, but then again you replace a bike's chain far more regularly than every 100k miles.
I've replaced cams twice, first time on my S2 coupe which had missing teeth so was a no-brainer (sorry; I don't recall the mileage that car had on it) and second time on my cab which had about 143k on it at the time. In that case the case hardening was showing signs of failing on the cams so I elected to replace them rather than try to get some more miles out of them (on the advice of my indie - who is a biker).
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