Chain keeper
thingiverse
This chain-keeper tool is a easy to use tool without getting dirty hands. Just move the derailleur aside and pull the chain from the cassette. Now you can remove the wheel and the chain stays in place. Last image: shows just a few redesigns towards a working tool :) https://youtu.be/Kue-aNoD9iM Used springs: Below the M4 knob : D=8mm, L=30mm, wire=0.7mm, pitch=4mm Ball lock; D=8mm, L=11mm, wire=0.9mm, pitch=4mm On the M6 bolt: D=9mm, L=18mm, wire=0.7, Pitch=6mm Different springs may work to, I used what I had lying arround.
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