^ Co-Motion specifically will not warant a Gates retrofit. According to them the BB's have to be exactly parallel. Before the Belt drive, they didn't allign the frames to the same tolerance that they do on the new ones in that regard.
If you get the chain line exactly straight, (which you can fine tune by sliding the eccentric side to side) and it still walks, it may be that the BB spindles are not precisely parallel.
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You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.