Most likely caused by insufficient torque on the axle nut, torqued by Google-graduated armchair engineers "iT dOeSn'T nEeD to Be ThAt TiGhT"...
I have had a think about this and, while the failures may be due to “user error” (spindle torque, trying to adjust without undoing spindle nut etc), looking at the loading in the adjuster: The wheel will want to move forward if it is unrestrained, this means that there is a tendency for a tension load in the sliding part of the adjuster and adjuster bolt as these help to restrain the spindle from moving forward. This could lead to fatigue failure in the tension area of the adjuster where shown by @t3scn . As a “belt and braces” failsafe idea, instead of attaching the adjuster to the swinging arm using the button head bolt provided, one could use the existing Ducati bolt/locknut to attach it. Once the chain is correctly tensioned using the Gilles adjuster, the existing Ducati bolt could be backed out so that it touches the forward part of the Gilles slider (similar to the Ducati method). Once this is done, the Ducati locknut can then be tightened up against the fixed part of the Gilles adjuster to hold it in place. It may need a washer under the nut to spread the load but that wouldn’t be a problem. If the Gilles adjuster did fail, the spindle would not move forward as it is up against the head of the original adjuster.
Sounds good! @Exige - how many were you after?? Not sure how much @Jamie Clare can do them for but we’ll let you know!
1 set (anodised silver if poss) with the wiggly bobbin bits too - do you have a set of them to copy? Don't mind if the design / shape changes slightly to get round any Design Right restrictions I'm sure there will be quite a few required by owners.
I use standard bobbins for my stand so don’t have any “wiggly bits” (stand lifters). I believe these can still be bought? https://www.averysmotorcycles.com/p...0c50R-v9CaLFBGvPXXxS9DjQ9MEysc7hoCT6wQAvD_BwE https://www.ebay.co.uk/i/3335477160...KbHaWhkIGIxGNtaTB3THQCNOVgePmD2BoCUfcQAvD_BwE