You will ultimately have to make the decision if its trash. I think you should disassemble and inspect. There probably will be marks on the steerer tube. If the marks on the surface, perhaps the clearcoat is just damaged and not a big deal. If its gouged the carbon may be compromised. If there is any doubt, show a mechanic you trust.
Ive been riding carbon seatposts for years. At first I was concerned about clear coat damage where the frame seat post clamps to the post. I used to take nail polish and "repair" whenever I was maintaining the bike. Now, years later, I dont bother with the clear nail polish - its just a hassle. I think we dont give enough credit to how strong CF components are and how well they stand up to surface defects.
I had a carbon steerer tube that was getting dented from a sharp, inside edge of the stem. I didnt notice until months after installing. I removed a few spacers and filed down the stem sharp edge so that the dent, was out of the high stress area. I feel comfortable using the fork now that I addressed the issue, but I dont think I would continue riding the fork if the dent was still in the high stress area and the sharp edge was still banging on the steerer as I bounced down the road...
On the other hand, is a fork failure worth saving $300? Probably not, but Im cheap that way!
Last edited by tj90; 09-21-10 at 06:01 PM.