Common question here - my RD barrel adjuster is not working. It just spins and spins loosely when the cable is clamped - I can't get it to convincingly loosen or tighten.

My FD barrel adjuster works fine, in comparison.

I suspect my RD barrel adjuster is broken, but I can't see anything physically broken on it. I know some barrel adjusters require pulling/pushing the barrel before it adjusts, but that doesn't seem to do anything on mine.

Is this part replaceable? I was looking on Amazon for a replacement, but the ones I came across were mainly for frame-installed type barrel adjusters. I actually bought a Jagwire one, and it didn't work - turns out it was for a frame-type barrel adjuster so it was like I was missing part of it, I believe.

I also know there are inline adjusters - I actually will be installing a Jagwire inline adjuster for my RD (I did one for my FD, worked great) but I'd still like a functional RD barrel adjuster.

If I'm missing something obvious (very likely), lemme know!

You have permission to Try

some RD never came with them.. MTB ones often just have the one at the handlebars.

Inline cable adjusters are always a possible solution.





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Jagwire has a few inline adjusters. Go to the small parts section of their web site.

If it's snapped off in the RD body the hard part will be getting the piece out.

You didn't mention Brand/level, but if it's a cheap RDER, get another similar one or slightly better.

If you try to back the adjuster out, can you remove it? If you can, and the threads in the derailleur are good, you can replace it. Otherwise, I'd just use the inline adjuster.

Go to a bike shop with the derailleur in hand and ask the mechanics nicely, and they'll probably give you a new barrel adjuster.

One of the guys at the co-op drilled a downtube adjuster out last week. He had to twist a small drill bit in his fingertips as he "twirled" in back and forth. He chased the threads with a tap and small crescent wrench. It took him most of the day but it was the kind of unique little job that had it's own sense of accomplishment.

Are you sure you just haven't backed it out to the point where it's not engaged with the threads anymore?