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..as the title suggests, my chain suddenly lost all tension on a ride on Saturday late afternoon (at the bottom of BKB in Surrey Hills with car at the top CP 👿 )
I didn't hit anything and only noticed when I started to ride back up the BW to Radnor Lane. Nothing appears damaged although the black clutch button wouldn't depress
Any ideas for a bit of DIY repairs?
You probably had a chainsuck episode and the cage went too far - the stopper bolt went past the cage lock zone and got stuck on the other side (silver bit in red ended up at the green circle). Seen it happen before, relatively easy fix.
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Diagnosis sounds correct/plausible
All happened as a started again up a BW (midly steep, so under tension)
Further tips for a numpty would be welcome!!
The little button seemed to be locked (between your two highlighted bits)
Once you confirm that the silver bolt is indeed under the cage lock button and prevents it from working, you can start by removing the button (it has a circlip on the other side).
Once the cage lock button is out, you can try forcing the cage back to its normal position; failing that, you can try moving the silver stopper to an accessible position (green circle) and then undoing it.
I'm pretty sure you shouldn't need to remove the cage/access the clutch mechanism (although we ended up dismantling it).
Thx
hopefully will have some time tomorrow to have a wee look
Turned out to be tiny stone had lodged in clutch - all sorted in 2 mins by tech wizard!