u/jkasephoto

Hey everyone,

I'm trying to get a reality check on a possible mechanical failure before I head out on what will likely be a 2,000 mile motorcycle road trip to Yellowstone, that I'm supposed to leave for in the next few hours.

Tonight I was doing a pre-check inspection on my, new to me 2018 BMW K1600 GTL with aftermarket crash bars. During the pre-check I noticed one of two mounting points on the engine case (the "boss" where the guard bolts to the bike) has partially broken off. It's not a main engine mount; it strictly holds the crash bar and a fog light.

A sliver of the aluminum lip on that engine boss sheared away, presumably when the previous owner dropped it, leaving a rough edge. The bolt is still secured, though if I press on the guard with my hand, I do get a little bit of movement, as illustrated in the video. There is a tiny gap between the guard bracket and the engine case that has existed there likely since the engine guard took the brunt of a tip over. When I am sitting in the saddle and rest the weight of my leg on the highway peg, the crash bar flexes about 1 to 2 mm. Because the bolt is acting like a pivot point, that foot pressure actually levers the bracket inward and closes the gap against the engine case.

I uploaded a few pictures so you can see exactly what I am looking at:

Image_001: Shows the overall layout of the guard, the highway peg, and both the upper mount and lower mount.
Image_3: Shows the small gap indicated by the red arrow that "closes" when I put my foot on the highway peg, but is otherwise there all of the time.
Video: Shows me pulling down on the highway peg with my hand

Because the damage is so relatively small compared to the size of the boss, I figured it was fine. But I was talking it over with a buddy of mine who mentioned that letting it flex back and forth over and over again on a long highway trip is going to act like a lever, and potentially cause a major failure.

My concern is he might be right... that the continuous high frequency engine vibrations and road bumps over thousands of miles, combined with that 1 to 2 mm pivot movement pressing into the case, will stress the metal enough to cause a crack to develop in the engine head or engine casing around that upper area.

Are my concerns about resting my foot weight on this peg warranted? Is a tiny 2 mm chip and that slight pivot movement actually enough to risk cracking the engine head under highway riding, or am I completely overthinking the physics of a footrest here?

Would love to hear from anyone with a mechanical or chassis background on whether I should just ride out or pull the pegs off before tomorrow morning.

Thank you!

Looking for picturesque spots in and around Cleveland to photograph a big Mack garbage truck!

Leaving for a 2,000 mile motorcycle trip in a few hours: Is a 2 mm chip and that slight pivot movement actually enough to risk cracking the engine head under highway riding? Looking for an engineering sanity check.