Finally got round to removing the rear wheel today. Discussed with a few mates, and its going to be an easy fix I think, as the bolts didn't screw into the alloy of the hub, but into captive steel nuts, countersunk into the alloy, see pics. my plan is to get five high tensile bolts, push them through from the inside, and the use locktite, and nylock nuts on the outside of the sprocket, as per most Jap stuff. I will make up new tab ring in a heavier guage, as the buckled one is thin tin. also I'll fit strengtheners in the web between the bolt holes, to stiffen and reinforce the whole thing. Hopefully that should do the job, though I'm open to suggestions of course. I could get the holes alloy welded and redrill them, or drill and sleeve them, but I don't think it will be necessary.
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