The ride out to gay head is worth it, but it'll be a zoo of frustrated cars, mopeds and glacial fellow cyclists. Go early in the morning. I was out there a couple summers ago and the best riding I could find was doing hill repeats on middle road. I'm not sure if they'll let you into lucy vincent on a bike, but if they do, jump on it, it's an amazing beach.
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Shimano : Click :: Campy : Snap :: SRAM : Bang