"....the chain looks to have lots of adjustment left, based on there being more alignment lines behind the axle and in the front of it...."
I doubt if i adjusted my last chain by a few mm max, the better quality chain you get the less messing about with it.
Ignore the price, you can find cheaper http://www.yamahamotorcyclespares.co.uk/spares/partImage.asp?GPN=3502725&uid
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