Cannondale Synapse 105. Nearing the end of a ride, I started to sprint in my highest gear. Derailleur randomly snapped at the hinge and the bracket at the back.
Yikes, QQ does your 105 also have a quick release skewer in the rear and thru axle in the front? Have you used used your bike on a trainer before? Picking up a trainer, but on the website it says it has a 130MMx9MM QR skewer, but no one seems to know if that’s actually correct.
joepublicschmoe on
Zooming into your 3rd photo which captured the fracture site. That is some serious corrosion there.
If I have to guess, the corrosion gradually weakened the alloy in the linkage until the forces from the derailleur’s return spring (which is quite strong) pulled it apart. I wonder what could cause corrosion like that.
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Yikes, QQ does your 105 also have a quick release skewer in the rear and thru axle in the front? Have you used used your bike on a trainer before? Picking up a trainer, but on the website it says it has a 130MMx9MM QR skewer, but no one seems to know if that’s actually correct.
Zooming into your 3rd photo which captured the fracture site. That is some serious corrosion there.
If I have to guess, the corrosion gradually weakened the alloy in the linkage until the forces from the derailleur’s return spring (which is quite strong) pulled it apart. I wonder what could cause corrosion like that.