I recently did the "Bike" portion of the Hike Bike Kayak experience. It was a fabulous experience! Our guide was good....he spent some time on some refreshers of bike riding/safety - especially important as the beginning of the tour was spent on a high speed descent down the hills of La Jolla!
The coast is beautiful and we had lots of opportunity to look at the harbor seals and sea lions and other wildlife/plant life. The guide was very knowledgable on all of these items.
One thing to note although the beginning of the tour was a breeze due to all downhill - there were some aspects that required a little more exertion including some hills and walking the bikes along the cliffs. The guide/group was patient for those of us who needed some extra time though.
This was a unique way to see the area and an all in all good experience.