| Imagine the rear of the swingarm is the same size as the wheel.
Now imagine the wheel doesn't have any spokes but is just a big cylinder with a lip for the tyre.
Next, picture a massive rear axle that only just fits inside the wheel rim.
Finally, hollow out that rear axle so that you can see right through to the other side.
.......I think....
(Is there another way to do this?) | 
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