Sorry Mate, I can't help you with bar-end thread as I swapped to Renthals at the same time as installing the BBs.

Without sounding like an ar5e, I think I have read older threads on this forum about the threaded bar and a search may be help. While you are at it, search for Yamaha hand-guards as I believe these are re-branded Acerbis and use the the thread in the bar?

I have never had the bar-end weights on any bike previous and I think I am used to the vibrations (if there are any), therefore, I didn't bother with this one either.