duhherro

hey guys i recently found a fingernail sized dent with groove marks next to the bottle cage on the seatpost of my fuji roubaix acr 2.0 and i'm not sure how it happened. the lined grooves in the dent make me think only a hard tool could've cause the damage. i know no dent is good, but do i have to worry about this/is there any way to fix it?

TornadoCAN99

Very odd. Sure there's no other mark on the opposite side of the tube? The grip marks seem to be the wrong direction for something like a pair of slip-jaw grips...should be 90 degrees to what's shown, assuming they were applied around the tube, not in line with it. Could a mechanic's clamp have been used on it without suitable protective cushions?

Hard to say how much the structure is compromised. Is it a steel or alu frame? If you keep riding it take steps to seal the surface from corrosion.

fietsbob

Was Someone trying to break open your U lock?

Well it is a rather difficult place to try to bang it out from the inside..

Did make a tool years ago to bang outwards from the inside .. Aka a 'snarling iron'
an S bend in a long piece of solid steel forged on the anvil , blacksmithing..

clamped one end in the bench vise, the end beating outwards on the opposite end,

hitting it on the end close to the vise, with a Hammer ,
made it rebound back, hitting the target area opposite in the process..
on the other end, inside..

CACycling

Looks like maybe a bolt caused it? As it is an aluminum frame, I'd just hit it with some touch up paint and let it go.

duhherro

The first thing I did when I saw the dent was check on the other side to see if there was a reciprocating mark, but there was none. From where the dent is I feel like something big and heavy fell on it or bumped into it as it's a very difficult spot to hit because it's right next to the bottle cage. It is an aluminum frame and I do plan to continue riding this bike(it rides very smoothly and I love it) but I'm not sure there's much to do besides touching it up. It's kinda too far down the tube to pop out with a tool.

bradtx

duhherro, Just keep an eye on it for any expansion cracks. Really an odd place for a dent, any kids?

Brad

TornadoCAN99

With autobody dent repairs, there is a technique that uses a small hole drilled into the dent, then a tool is inserted/expanded and pulled to pop the dent out. Hole is then filled/repainted. That works for large panels and relatively thin wall....a bike frame is another matter.