Every flight on Singapore Airlines out of SFO appears to connect in Hong Kong with just 1 hour layover. Can someone that has flown this route tell me how this experience is? Is the 1 hour layover really enough time? Do I not have to clear customers in HKG before boarding my flight continuing on to Singapore?

I'm a bit nervous with the 1 hour layover time but it's really all that is available.

Thanks!