What threads are used on Avid BB5 barrel adjusters? I thought I might replace the locknut on my front brake barrel adjuster because the current knurled one needs pliers where it sits in an awkward place behind the mudguard stays. But it's an unusual thread. It's bigger than M6, but it's 1mm pitch (or 25tpi) An M6 screw seems to engage the female thread but pulls straight out. Their _in-line_ barrel adjuster uses M6 threads, and I could fit one of those when I re-cable anyway, locking off the one on the brake - but I don't plan on replacing the cables just yet.

They did indeed turn out to be M7 (1 mm pitch).

Nuts are fairly easy to get, but at least the locknuts (half nuts) I bought take an 11 mm spanner. None of my multitools, or any I can find online, have this size spanner built in; even my workshop spanner set omits it, but in over 20 years of building and maintaining hardware for work and play, this is probably the first time I've handled M7 parts.