The front disc brake grinds after a light accident with full braking and plunge.
To give an idea of the forces involved:
The bike fell to the left, mostly cushioned by me. The bike had no more linear
momentum. The brake lever and handlebar band has minor scratches. The handlebar
or stem is slightly skewed.
- It look like the wheel/rim is not deformed/buckled, it's not visibly
wobbling.
- The disc is slightly deformed, wobbling at most a couple of 100µm. The
bending cause by the pads looks more than a millimeter.
- The gaps between disc brake pads are not even, one pad is always touching
the disc. The disc seems to be not centered in the brake.
- The handlebar is slightly skewed (de-justified stem/steer tube).
The animation shows the brake photographed from the front toggling with brake
released and slightly, but not fully pressed:
![Animation: detail shot of the brake toggling between braked, slightly braked](https://cdn.statically.io/img/i.sstatic.net/eX6zZ.gif)
From the animation you can see that the brake pads are not evenly spaced. On the
left (inner) side there's a (wide) gap, while on the right (outer) side the pad
is already touching the disc. Also, the disc is being pushed and bent by the
outer pad moving.
(Note that the animation was created from two photos taken with the bike
standing but being unfixated and the levers being operated. This causes some
minor movement of the whole bike. If you think this makes the judgement
impossible, tell me and I'll try to make a better pair of pictures.)
The animation shows the wheel spinning in 90° steps, photographed with sharp
angle to (along) the fork:
![Animation: wheel spinning in 90° steps - the disc is wobbling slightly](https://cdn.statically.io/img/i.sstatic.net/TBmWW.gif)
The wobbling is quite visible.
There's no more than these scratches caused by the plunge:
![Minor scratches on the handlebar and levers](https://cdn.statically.io/img/i.sstatic.net/yWYCe.jpg)
Technical data
- Gravel bike
- Carbon fork
- Through-axle
- Aluminium drop bar
- Shimano 105 BR-R7070
- 1200 km driven, 4 months old
- Bike: 10 kg
- Saddle bag and water bottle: 3 kg
- Me including backpack: 65 kg
Course of events
This is after full braking and a - presumably - light plunge from standing, with
rear wheel lifted, to the ground, with negligible to no momentum, not a crash.
The full braking ended with me stopped, the rear wheel lifted off the ground,
the bike angled 45° - 90° and the saddle in my spine before I fell fore- and
sidewards. So I pushed downwards and sidewards (along the axle, not in driving
direction) into the stem with my body weight and a bit remaining momentum. There
probably was torque by the fork into the axle.
Questions and guidance
Is is possible that the braking energy itself might have
- deformed the brake?
- deformed the disc?
- damaged the wheel hub?
- deformed/invisibly fractured the carbon fork?
I'm pretty sure the bike pluging did no major damage.
What was stressed most during braking?
What components shall I replace (apart from re-justifying) to be safe?
Apart from asking a professional bicycle technican for an estimate, are there
things I can check for myself?
Might the fork be damaged by the aforementioned forces?
More background
This happened during a light traffic accident.
Ask for details
Ask for details, more part numbers, measurements or other photos (i.e. of the
scratches) if required to gauge this. If you think there's too much distracting
information, tell me and I'll remove it.