Replaces BMW part 33 17 1 230 296 (33171230296)
I've lost a number of swingarm endcaps on Airheads. Finally, I found a reasonable solution that seems to be about the same price as the OEM part.
It's a nickle plated steel "finishing plug". On McMaster you can 25 at a time, product code is 9563K51. I've also seen that code listed elsewhere, also on Amazon (though with significant markup). If you need it for multiple bikes, you should probably order through them.
It fits quite snuggly and flush with the bike. Quite hard to take out without a screwdriver, unlike the OEM part. The OEM part is probably completely fine depending on the boots you have. I'd only recommend buying this if you've already lost at least one of your end caps.
If not, considering shipping, I can send a pair for less than you'd get the 25 for, but it's not nearly as good of a deal. Right now I can ship a pair to the lower 48 for $10, all in. I'd like to bring that cost down if I can figure out a cheap and consistent shipping method.
I don't yet have any kind of online physical good sales together, so this is just a manual process.