SEPM/LUA - Clu-prod space disk too big

Hi all !

I've got 150-200 clients computer.
I've installed on the same windows 2008 r2 server SEPM & LUA.

Today my clients are migrated to SEP 12.1 RU4
I've setup my LUA (preferences options) to move update to other folder (an second partition). So this partition is 23 GB used (it seems ok for me for the 2 products I update sep RU4 & sepm 12)

The problem is my Clu-prod folder, it takes almost 63GB of my system harddrive.

I setup my LUA to keep 1 old revision, but this folder should have approximatively ths same size than my second partition right ?

How can I clean it please?

Regards