DONT forget to order and replace also allways the sinter bearingbus on the machine because to protect you from a dissapointment because otherwise the belt will turns off and cant be (good) controlled again , replace the drive roller allways and clean the front roller axle if its only dirt on the front roller use a little sillicon grease film on the front behind can use a little bit more sillicon grease between the axle rings and new bearing bus. remove the dry grease in the driving gear space and renew the lubricant in it with a multipurpose grease .