After much searching and reading of all the bicycle tours to choose from, I have opted for absolute explorer. http://www.absoluteexplorer.com/index.htm
I have looked through their website for their meeting point (for the half day tour) and cant find their meeting point.
We fly into bangkok at 7.00am and plan to do the trip which starts at 10.00am. I know its a bit tight, but we're only in Bangkok for 1 day/1 night, so this is our only opportunity, and have done all the temple/rose garden/floating market thing last time we were in BKK.
We are booked to stay at Holiday Inn, Silom Road but may cancel the booking if its too far away from the meeting point. Bearing in mind soon as we arrive at our hotel 08.00ish we'll be off to bed for an hour. So less travelling to the meeting point will be better.