| This is a common problem when fitting a 180 rear tyre, happened on my bike without any changes to gearing etc.
Solution without fitting longer chain and/or adjusting the ride height is to drill a small hole in the bottom side of the hugger on the side away from the swinging arm, where the hugger has no support, then put a cable tie, or lock wire from this hole to the bracket on the exhaust where the pipe springs fit. This just lifts the huggewr enough and gives enough support to clear the 180 rear tyre and has worked for me. | 
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