Replying not as a frame expert, but I did work as a mechanic for a while and was often customers' first line of inquiry about frame issues. Take my advice with a grain of salt. The only authoritative source of information on this would be a framebuilder who has been able to inspect the frame in person.
All that being said: -I would agree that that looks like a cracked seat lug. If my understanding of frame construction is correct, that also means the top of the seat tube is cracked, since it extends through the seat lug and is cut off even with the top of the lug. -A crack there would be a big deal in that it would eventually cause the frame to no longer be able to clamp the seatpost. The tension of tightening the seatpost binder bolt would tend to expand the crack, and eventually the seatpost would start to slip. Riding it in this condition would probably accelerate the process. -I'll let you evaluate what is an acceptable amount of danger for yourself, given the failure mode I've described above. -I would imagine that something like this could be repaired by a skilled framebuilder, but the questions would be whether you could find one that was willing to take on the work, and, depending on what they charged, whether the repair would make sense financially. It's a tricky repair being at the seat cluster joint, where four tubes come together, rather that at a joint with only two tubes, or better yet in the middle of a single tube. Given that the crack is also through the seat tube, a repair might necessitate replacing that tube as well, although a framebuilder might be able to cut it off somewhere in the middle of the tube and splice in a new section to run through the seat lug. I don't know where you're located, but as always, finding a local builder who could look at it would be ideal. Good luck! -Jeremy Till (former orange QB owner myself) Sacramento, CA On Tuesday, January 23, 2024 at 11:07:41 PM UTC-8 [email protected] wrote: > Hello, > > I am seeking information about what looks to be a small crack in the seat > lug of an orange Quickbeam. The reason I think it’s a crack in the lug and > not just the paint is that it is visible from both inside and outside the > seat tube. Pictures attached below. > > Some questions I have are: > - Am I diagnosing this correctly as a cracked seat lug? > - Is a crack this size and in this location a big deal (I’m assuming yes), > and if so, how big of a deal? > - Does this render the frame dangerous to ride? > - Can something like this be repaired? Is there anyone that’s had > something similar repaired who can share their experience? > > Thank you for any information anyone can share or point me toward. > > Logan > > -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/rbw-owners-bunch/6099f09b-63a0-45a8-ab33-90dd8192f53dn%40googlegroups.com.
