Many years ago I got into cycling in a small way. I never rode in any fun rides or cycle tours, and never trained with friends. I bought a racing bike and started cycling around Cape Town, up to Melkbos (along our west coast), and around to Stellenbosch (the heart of wine country). It was awesome. Then Kerry-Anne came along and there was no more time left for riding my bike. :) In fact, I haven't ridden a bike in several years.
I discovered a company called Downhill Adventures that looks really cool, perhaps more so for visitors to Cape Town than locals. I haven't tried them out (so don't take this as a recommendation, please), but it seems as though one can hire proper, hardcore, mountain bikes from them and join trips on the slopes of Table Mountain, in Tokai Forest, and plenty of other places. It's always safer to cycle in a group when out in the middle of nowhere (which is exactly what it's like in the forests of Table Mountain), so I think it's great for people visiting Cape Town to be able to join others on a trip.
We should give this a bash some time... it would be fun cycling in the forest. The only concern that I have is regarding our fitness levels... I fear it would be insanely embarrassing. :D