I followed the poor instructions in the manual. The terms they used weren't in the sketch. It was almost impossible to put the nut back on - the bolt was so short. I was careful to insert the stubs into their slots on the plastic cover. The chain should be adjusted, but it doesn't say how/where. There is a loose adjustable metal part, but it doesn't seem to move anything when I turn the screw slot which is lengthwise to the chain.