Display MoreDDM bar is hollow like the oem bar, but thicker walled and therefore stiffer, its the Twist bar like I have that is solid, Also the oem end links seem to have changed over the years, the links on my 2016 are thick and the same diameter for the entire length, the later ones I have seen neck down and get much thinner in the center than they are at the ends - these are the ones I have seen pictures of on here getting bent and damaged when the sway bar shifts - If my sling had these end links I would have changed them out when I got my sway bar
as to how the sway bar works it acts as a lateral spring between the suspension on the right and left sides of the vehicle, this "spring" acts to try to hold the vehicle flat when the suspension on one side is compressed by using the sway bar to put pressure on the other side to compress it.
as to your point about "small little rods" - I agree that the thinner oem end links on later slingshots would probably be a weak point if going with a really stiff sway bar and should definitely be upgraded at the same time
As to the weight issue of a solid bar I dont think its an issue anymore than adding weight with any other mod, the actual weight of the bar itself is supported by the sway bar mounts attached to the frame, if there is any additional weight actually placed on the end links I suspect it is very minimal when compared to the other forces applied by the suspension moving - even with the stock bar
I am not really an expert on this, but if you want more information I am sure Dave@DDMWorks can help
There is not a huge weight penalty going to a solid bar in the front compared to the hollow bars, the difference is mainly how stiff you want the front to be and how much you want to turn the front end into a solid axle ;).
I have not seen any failures of the stock end links, except when installed on the forward holes on the Twist sway bars. The forward holes (which are stiffer), put the end link at a pretty steep angle and also cause it to hit the tie rods at full lock and is something that should be checked for when installing the sway bar and end links.
Let me know if there is anything else I can answer about this,
Dave