Fit some Machine Art X-Head covers or just accept the rockers will get scraped and replace when needed.
The OEM Adventure petrol tank bars do the job. They are not heavily mounted but will protect the plastic tank from impact and scrapes. The OEM engine bars however are worse than useless.
I had a slow speed fall off (very muddy back lane). OEM Adventure crash bars and Touratech head protectors. I was lucky the crashbars and head covers did not cause even more damage. They transfer heavy loads to small parts of the cylinder head and/or engine case. On top of that the rocker cover was still scraped.
The RHS crash bar bent back into the cylinder head, shoving the rocker cover backwards until it was stopped by the rocker assembly inside. The crash bar bottom mount was bent and wedged hard into the engine sump.
The Touratech head protector has stainless steel mounting lugs with zero "give" and actually bent the M6 mounting screws into a Z shape. Any more force would have cracked the cylinder head. They also failed to protect the mag cover from being scraped.
I have since removed both engine crash bars and fitted Machine Art X-Head covers. They are pretty stiff (made from polycarbonate) but I hope they'll "give" or at least hit the rocker cover itself rather than over-loading the mounting lugs.
The cylinders really are the strongest part of the engine, but the rocker covers are fragile. IMO, protecting the covers is all that's needed. With the costs of replacement used covers on eBay you could even argue it's better to just replace a scarred cover.
Magnesium does crack all too easily. Soon after, I hit my LHS rocker cover on a kerbstone and cracked it (engine stalled on a steep LH camber). The TT head protector and OEM crash bar did all of nothing. An X Head would have saved it. Thankfully I did not have the third tumble around the same time.
In short - fit some decent head covers but DO NOT FIT ENGINE CRASH BARS.