Can anyone speculate or explain how this damage may have occurred to these fork arms? Would you pass up this bike due to this damage? Thanks for any input!!!

That Picture inadequate, I'd have to see it in person.

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...that's not something I could assess from a photo on the internet. sorry.

Yeah, really hard to say from that photo... It almost looks like it could just be gunk, like if some tape was there or something.

Be sure that is just cosmetic before you ride it. I got home on a fork with almost exactly that as a full crack. One cm higher, right under the crown. The bike was shuddering wildly every time I hit the front brake so I rode the last 5 miles rear only. Front wheel passed true on the wheel stand with flying colors. Went back to the bike and gently spread the forks. Right blade bent out 8". I turned, walked back into the house and sat down, shaken to the core. I descended 2000' that ride.

Lesson learned: If you nickle plate a quality steel fork, make sure the plater heat treats it properly to drive off the embedded hydrogen molecules. This plater didn't (and didn't say anything). Your fork won't have that issue but if that is a crack, you could have the same experience or worse. (I babied the bike down the descents because of a completely unrelated mechanical. Could well have saved my life. There was a corner half way down that I love to come into hard, slam the brakes and rocket around. Tight but nicely banked.)

Ben

Those appear to be stress or fatigue cracks in the tubes. If so, get the butter because the fork is toast.

As to the cause, it could have started with corrosion, or the stress of the fork being ridden while spring apart a bit, or any number of hard to pin down subtleties.

But a crack where you have it, especially in both blades is the second problem ou could have with a fork. (the worst would be similar damage at the base of the steerer).

Looks like the middle arrow is pointing at a spot that's dented.

Depending on what all is on the bike Campy-wise, if the price is right I'd still buy it. Strip it, recoup what you can selling the bare frame on the 'bay.

If it's Italian thread on the Campy stuff and they want $300 or less for the bike, LMK. I might be interested if you'll strip and ship (I'd take everything but the bars and frame).

The symmetricality of the marks makes me wonder if they might be due to a clamp of some sort.

Cannot recall seeing an accessory which mounted in this spot but its always a possibility.

Have you tried asking seller about it?

It looks more like something got caught in the wheel as the person was riding or while the bike was rolling forward. Forward motion of the wheel and spokes would've carried whatever it was right into the fork and left a linear mark like that. I think it dented the right-hand (from our perspective) fork blade as well. Shocked it wouldn't have broken the spokes (or maybe it did?), but ...

Thanks for this interesting suggestion.

Had ruled out coldsetting/resetting as marks not correct for that.

Think this is a good idea.

not sure if there's a dent or just reflections in the chrome.
Very mysterious and I have no good theory but would proceed with caution and inspect thoroughly...looks like a nice frame, otherwise...what make? (looks De Rosa-ish but I'm being hopeful!)

chrome plating, as an electro deposit can be removed thru the same process, reversing the current,

and then once back to bare steel you can re asess the damage if any to the base metal .

polish it smooth then have it Re Chromed.

I think it's pretty clear from the responses that we're guessing off of your pictures. Take it to a reputable shop or frame builder for assessment before riding. It could be just tape residue, rust from clamps, or cracked tubes. I'd hate to tell you what it is if I didn't have it in my own two hands.

This is from a frame and fork that is for sale on eBay. The seller is being a real ass about providing additional pictures or an explanation and seems to be a little ignorant about the details. He is not even mentioning this in his description. Here is the listing....

Looks to me like the fork has crown supports between the blades. The apparent damage seems to be on the supports, also, suggesting to me that the marks might just be dirt or debris, of some kind. Look at the other pictures on the listing and you will see a similar mark near a drop-out...



Of course, I could be wrong. Also...

If the seller is uncooperative now, walk away is all I can say. The frame might be just fine, but the seller might prove troublesome

I noticed the same line on the lower blade that randy points out^ also makes me think it might be something more like tape residue...but really hard to be confident without some confirmation from a responsive seller, or holding it in your hands.

The fork definitely has inside crown supports between the blades.

...run away. Do not walk away.

Seller is like my first wife. We are no longer communicating.

I guess I need to treat him like my first wife and move on.

This.

Except, RUN AWAY!

I think it's just crud. But I don't know if I'd risk it with an uncooperative seller.