Hello Folders, Can anybody tell me if the rear hub of my 2013 Dahon Vitesse 8 speed is a sealed unit? Years ago in the CTC magazine was a article about the 'Zerk Lubrication System' which pumped grease into bearings thus saving dismantling same to change the old grease. I drilled the hole in my rear hub and started pumping in the Lithium grease. Unlike the front hub no grease started to erupt past the outer casing...it must be 'tight' in there...is the hub at the back eeerrrr...sealed??