Tiagra Rear Derailleur Repeated Cable Fraying

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Eyebrox
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Re: Tiagra Rear Derailleur Repeated Cable Fraying

Post by Eyebrox »

I have checked the 2022 Shimano dealer manual and the longer cage 4700RDs are shown with the cast adjuster section in the same position as the one in the original post. As stated earlier, it would snap if twisted in any way. Shimano in their infinite engineering wisdom must have decided that it would work at its best in that position. I have photographed a 4700 off the bike in a relaxed position with a loose cable through it. Shows how out of line the adjuster is with the anchor bolt.
IMG_20220514_150154081.jpg
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Mick F
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Re: Tiagra Rear Derailleur Repeated Cable Fraying

Post by Mick F »

Thank you for that.
Excellent photo.

Not excellent of Mr Shim though. In fact terrible. :cry:
Mick F. Cornwall
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Mick F
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Re: Tiagra Rear Derailleur Repeated Cable Fraying

Post by Mick F »

Here's my old Deore XT.
They don't have an adjuster, you have to use an in-line one.
Excellent rear mech, and the best bit about them, they don't have a top pivot! :D
IMG_1224.jpg
Mick F. Cornwall
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531colin
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Re: Tiagra Rear Derailleur Repeated Cable Fraying

Post by 531colin »

Jamesh wrote: 14 May 2022, 11:52am You cannot bend a casting it will snap.... ........
ImageIMG_5592 by 531colin, on Flickr
Jamesh
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Re: Tiagra Rear Derailleur Repeated Cable Fraying

Post by Jamesh »

531colin wrote: 15 May 2022, 2:36pm
Jamesh wrote: 14 May 2022, 11:52am You cannot bend a casting it will snap.... ........
ImageIMG_5592 by 531colin, on Flickr
Is it a casting or a cut off extrusion???
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531colin
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Re: Tiagra Rear Derailleur Repeated Cable Fraying

Post by 531colin »

Thats a good question, to which I don't know the answer! (or how to find the answer!)

But to go to something very familiar to all of us.....the bent ali. gear hanger on a carbon/etc. frame......
How are they made? My guess is they are pressure die castings? At least some have a step in thickness and I don't see how they can be a slice cut off an extrusion? I guess they could be machined from solid or forged, but either of those is likely to be expensive for a "sacrificial" part?

I didn't have a scrap R. mech. knocking about, otherwise I would have put a (pressure die cast?) bit of R. mech. in the vise and twisted that!
VinceLedge
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Joined: 12 Dec 2020, 9:51am

Re: Tiagra Rear Derailleur Repeated Cable Fraying

Post by VinceLedge »

Fitted the end cap with long cable guide, see how long the cable lasts!
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