Rental Bikes in San Fransico

A friend of mine and our wifes are visiting San Fansico for a few days during the middle of October. My friend is a very good duathlete and cyclist, especially in mountains. Me, not so much, but I do enjoy getting out for a spin. My friend normally rides pretty high-end gear - he has a bike for just about every occassion.

Rather than flying with our bikes, we thought about renting. Does any know if there is a place that we can rent some pretty decent bikes in San Fransico, or maybe north of San Fransico?

Thanks for your help

http://forum.slowtwitch.com/gforum.cgi?post=766558;search_string=rental%20san%20francisco;#766558

http://forum.slowtwitch.com/gforum.cgi?post=608861;search_string=bike%20rental%20san%20francisco;#608861

http://forum.slowtwitch.com/gforum.cgi?post=998019;search_string=rental%20san%20francisco;#998019
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