I bought a set of class retro mirrors and some bar ends to mount them on. My roommate and I tried to decipher the instructions they came with to get the right combo of parts for the bar end. The problem is, we can't seem to get it tight enough so that it won't turn. The bar ends and the mirrors came with different parts. We used the bigger of the two metal spreading pieces that came with the mirrors. We thought we had it tight enough that it would be ok, but as I was riding the mirrors started to rotate forward.
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Any advise on what we may have screwed up, or which are the correct parts to use would be appreciated.