 There are manufacturers who make the ROPS or roll bars for N's. Costs seem to range from $4xx to $6xx depending on who you ask. They are mounted up apparently as you describe. I've never actually seen one on an N to comment. Is it safe and effective? Questionable, especially if you weld it up yourself. There's a lot of forces that act on a very small area when mounted as you describe. Especially on a rear roll over. There was a study on this that had the ROPS failing at the mounts, ripping the mounts out of the axle housing. There was a fix determined by the study, and turned over to industry. But it is unclear if this fix was ever implimented. If it was not implimented, the ROPS is useless. In fact, it would be more dangerous then not having a ROPS at all. And, of course, if you don't use a ROPS correctly, it's useless again. If you're not going to wear the belt, don't bother with a ROPS. Consider a 4 point cage if you're going to build it yourself. For a two point, consider a pipe or bar going across the transmission to help hold it together on a rearward roll over.
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