i am 5 foot 6, 167 cms, what frame size should i ride, anyone got one?? normally a 16 inch mountain bike, so would say 52, but could i get away with a 49, i have found one cheap. 

Not very tall are you Serge.

When I rode a kona (jake) for cyclo cross racing I used a 54cm frame and i'm 182cm tall, ride a 19" mtb and a 57cm road racing bike. I still use a 54cm for cyclo cross racing, but it all depends on how you like it.