pycaffe: can import caffe / cannot import _caffe

[Lulailole]

Hello,

I have installed caffe in Ubuntu 16.04:

make all
make test
make runtest

make pycaffe
make distribute

I have added the pycaffe path to the PYTHONPATH and I can actually import caffe but it fails when trying to import _caffe.
I have tried to add the 'caffe_root/python/caffe' path (where _caffe is) to the PYTHONPATH but doing this will end up crashing up my numpy instalation =O!!
I thought it was a numpy versions conflict but it still behaved the same after removing all my numpy versions and reinstalling an unique one.
Any clues will be welcomed as all solutions found point to adding the folder to the PYTHONPATH (which is already done).

PD: just to be clear, when PYTHONPATH=caffe_root/python everything works fine but _caffe

Thanks.
L.