Recovery from prostate surgery seems to be a fairly personal thing, with some guys up and about quickly and others not so quickly. I have to say that I started walking and exercising about a week after surgery, while still with catheter. What might be the ultimate determining factor for bicycling is incontinence. If you leak a lot, then it might not be real comfortable to ride any sort of distance for a while.

If you are looking for a good prostate forum try HealingWell at:
http://www.healingwell.com/community/default.aspx?f=35