OK, above I simply put a lever-extension onto an allan key to get to those 4 sprockets. But now the name of the game is to apply the exact torque to tighten those sprocket-bolts. The Allan key can't connect to the torque wrench. So either you buy an expensive special 10mm hex-socket, or you do it like me and harvest a bit of the Allan key and stuff it into a 10mm socket... And there also a lot of excitement and hipe regarding a very special sprocket-key or whatever - I could not grasp the idea