Like D8veh said unscrew it (slight knock with a punch helps) then there is an allen key grub screw on the crank remove this then the whole unit slides out, but that's all you can do as the unit is sealed and is no use to you out so my advice is to leave it well alone never atempt to take it apart!!! I tried and failed (wanted to replace a bent crank) nightmare one way lockout washers holding it all together internally with pressed on bearings with optical pas right nightmare actually wondered how thay got it together ???.....
The other side is a nightmare too, Lol, Under the grey hub cap is the pas tourque mechanism pop this cap off and you will end up with a box of springs these are great fun to try to put back together under tension, Ask me how i know!!! Oh the fond memories..
If it is pas you are after, I would look into an aftermarket one.
Btw, i was fortuanate with my tourque crank as mine came with a whole spare unit when i bought the bike, just thought while it's off i will try to fix it, this was just after i fitted my Smax with a brand new clutch, which went considerly better than the the crank on a push bike ....
