Can we get more pictures of the setup? How the top link attaches?
In my opinion I'd say 1 breaks it is a manufacturing issue.
3 break in one season and it is more likely to be a set up or use issue. Unless the 3 came from the same batch, manufacturer, etc.
I's take them to an experienced welding/machine shop and see what they say the cause of the break is.
To snap a bar like that is highly unusual.
Also, were those bars replaced and where did they come from? Was the first break an original one?
Looking at a picture of the BH25 the bar looks to be angled where it bolts at the rear and not straight like his appear to be.
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