Hi and welcome to Cycle Chat.
What type of Cycling Club are you looking for?
For road racing there is
Avanti
For more leisurly rides there's the
Bromley and
Lewisham Cyclists groups.
If you are a member of the CTC there is the
West Kent CTC who organise rides.
And as Martin mentions above there is the regular Sunday morning Cycle Chat ride from The Dripping Tap (A Plumbers not a pub) on Masons Hill Bromley.
We meet there at 8.30am and head to Hyde Park corner at a brisk pace to meet others then on to somewhere for coffee/tea/cake at a more leisurely pace.
As you can see from my sig I'm another Orpington-ite.