At the rear of the swinging arm there is a large pinch bolt, slacken that then put the bike on the paddock stand (do not put the bike on the paddock stand then push the bike off it again undoing the bolt
).
Using the the correct tool on the the eccentric hub in between the sprocket and the rear wheel (you do have the tool?*) turn the hub clockwise or anti clockwise to tighten or loosen the chain.
Do the pinch bolt back up.
*if not you can tap it round with a screwdriver, but don''t say I told you that.
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