In my experience, Caltrain isn't too strict about bike capacity; I've been standing on the platform with more than 32 other bikes just at the one station-stop in Mountain View, and never has a conductor stopped people from boarding.
Your mileage may vary, of course, but getting there a bit early is never a bad idea.
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Originally Posted by patentcad
[Biking] beats smoking crack. But smoking crack is cheaper.