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Thorn eccentric bb alternatives

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humedavid:
Hi guys,
I was just wondering if anyone uses an alternative to the Thorn eccentric bottom bracket shell, what type and if they are they happy with them.
I've got an old ish Raven with the black shell. Lot of marks on the shell now so I've been thinking of going a different route and trying a different shell.
Cheers

PH:
Are you asking if there's an alternative insert to use in the same way, or if you can use one of the alternative systems? 
Those other systems are the wedge type and those I've seen and the one I've used were a smaller diameter than the Thorn shell so wouldn't fit. I haven't researched them so there may be one that fits, I'm not a fan, they require more maintenance and have a tendency to squeak.  Or there's the pinch bolt type Thorn now use which would require serious frame modification.  These are my preferred option, even more so now Thorn have simplified it to two bolts rather than the unnecessary four.
If you're looking for an alternative insert to use in the same way, there may be some. but they'll all function in the same way, so I can't see any advantage.  I prefer the pinch bolt type. but there's nothing wrong with the set screw type you have, the issue with wearing indents into grooves arises with too frequent adjustment, which just isn't needed.
I'd just get a new one and adjust less frequently.

humedavid:
Thank you for your reply.
The main reason is that my Raven does a double click when I pedal harder. I've tried many things, changed pedals, tightened and greased chainring bolts, greased cranks, removed the eccentric shell, filed off protruding metal bits, greased it, changed the whole bb to a new one, greased the seatpost etc. It still does it.
Getting a new shell from SJS Cycles is not a easy option as I'm in Europe mainland. But I think that's my inevitable next step. I did have a quick look at the different bb shells and you're right, they're different in sizing.

JohnR:

--- Quote from: humedavid on June 20, 2021, 09:22:04 pm ---I've tried many things, changed pedals, tightened and greased chainring bolts, greased cranks, removed the eccentric shell, filed off protruding metal bits, greased it, changed the whole bb to a new one, greased the seatpost etc. It still does it.

--- End quote ---
What condition are the chain, chainring and sprocket? I ask because I had some similar disconcerting noises on a bike with a Gates CDX belt drive. The noise sounded mechanical so I checked every nut and bolt several times but the noise persisted. Eventually I gave the belt a good scrubbing (they are meant to be maintenance free but still collect muck) and the noise immediately went away.

Danneaux:

--- Quote ---I've tried many things...
--- End quote ---
Try checking the saddle, saddle rail clamp, seatpost binder bolt and shim.

In my experience, Brooks saddle rails (if yours is so equipped) can "work" a little where they are riveted/peened to the rear steel cantle plate and so produce a click/double click with each pedal stroke. Inverting the bike and applying a tiny drop of oil (don't get it on the saddle leather) to the interface can cure a click of this sort for many years.

With other saddles I've had, the rails can click in the clamp. In that case, a thin layer of electrical tape can help. Check torque on your seatpost binder bolt as well. I had a double-click produced by one of my Thudbuster seatposts that turned out to be a faulty pivot bushing. Documenting my steps in an email to Cane Creek resulted in a warranty issue of new pivots and the tool to install them. Problem (and noise) solved.

Noises -- especially clicks -- can easily telegraph through a bike frame and appear to come from somewhere else. When I first encountered this I did the same as you, focusing on the drivetrain. I didn't conquer the problem until I checked the saddle end of things. Handlebar stem clamps can do it too. If you use the Forum's search tool and enter the terms "click" and "noise" (no quotes), a lot of suggestions will come up.

Best of luck on finding and resolving your clicking noise, David.

Best,

Dan.

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