I've not seen that kind of DIY on a chain before, I suppose it make sense once you have the correct sized bolt.
http://www.flickr.com/photos/nathanielsears/4428681658/
it it a screw that has stopped threads (tighten it down), and then on the other side you place an additional lock nut.
@jersey started
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http://www.flickr.com/photos/nathanielsears/4428681658/
it it a screw that has stopped threads (tighten it down), and then on the other side you place an additional lock nut.