My trainer broke my bike. Oops

Or maybe there just wasn’t enough pressure on the drops? Not sure…it was a standard 5mm QR w/ 9mm dropouts. Derailleur hanger is secured by two hex-drive flathead M4x12 bolts. One of them sheared off in the hanger.

As you may guess by the fact that it’s a QR gravel bike, the bike is quite old but I managed to find a derailleur hanger on line. Or maybe found one on line. We’ll see when it gets here. As a backup I’ve got a 2mm left-hand twist drill bit on the way. Either way some bike wrenching to occupy my time in the near future.

Anybody else shear off a derailleur hanger bolt? Or any trainer-induced breakage stories/advice?

Yep! I broke mine doing a 1100-1200 watt sprint a few years back.

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Nice “backdoor brag” there!!! :facepunch::facepunch:



I had a bent mech hanger on my trainer/road bike and I’ve not crashed her so put it down to the wheel on trainer somehow but that’s about the extent of any damage (I hope).

Not experienced it myself, but I have seen and read more than a couple of stories of bikes with open dropouts slipping out of trainers. It’s a good idea to check and reapply the QR once in a while. I check mine about every 2 weeks at least, when I lube my chain on the trainer bike.

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wowza - she ripped right off. do you ride to the far end of the cassette (high or low) or in the middle?

i want to make a comment that the dust / sand is responsible just to stir up a fierce debate…wait i just did

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I’m going with too much power :muscle: That’ll never happen to me :roll_eyes:

I have just had one of those hanger bolts retapped though.

My hanger mounts the same way but I’ve never broken the bolts though they do loosen up ever so slightly over time. Another win for Di2 :upside_down_face:

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Nah. I’ve dropped about 12 kilos over the last several weeks so I’m working hard just to hold onto whatever meager power I had.

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