OK so you have an aftermarket sprocket which maybe fine. On the diagram, part 23 is what essentially keeps the sprocket from coming off the shaft. Key is that once you tighten the two bolts that position and hold part 23 to the sprocket, you need to have the front and rear sprockets inline. As long as you have them aligned you should be fine. The sprocket does float a little from left to right but should not be forced to one side or the other by the chain as that would cause excessive wear on both sprocket and chain.

If you install it one way, then the other, with the chain and rear sprocket, it should be obvious. If it's not working either way you should reconsider using it. I imagine you could shim it, but I don't advise that when the correct sprockets are available.

Eric
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MC28 SP