grant40

Probably not. This is what happens to a high end, steel racing frane that has a lot of rust. The thickness of the tubes is VERY thin.

zandoval 

I am not a builder but it would appear that after stripping off the paint and cleaning you could identify the extent of the crack. It looks like it could be the top of the seat tube and may extend through the tube. If that's all it is I would drill a small hole through the crack and extensively clean with a Phosphoric wash the crack, then just Silver Solder it.

Of course that is if its a steel frame. If it's an aluminum frame I might try the same method but use a milder acid for the wash and definitely not a base. I then would try "Alumiweld" to fill the crack.

But that's just me. You must realize that more than just a few of my ideas have failed... Ha

All in all you are going to have to strip the paint and find out the full extent of the crack before ya bring out the torch.

Andy_K 

No, the seatpost came out. (Too soon?)

verktyg 

I'm guessing but from the Vintage Trek website the bike looks to be a 1981 Trek 616 model. The 3 main tubes are butted Reynolds 531 with a 0.7mm or 0.6mm wall thickness at the top of the seat tube. The rest of the tubes are "tubing"...

https://www.vintage-trek.com/images/trek/Trek81.pdf

Aside from some surface rust on the top tube the rest of the spots are paint chips and scratches plus the rust showing through the crack.

Trek 616 bikes came with SR Laprade P5 seatposts with a 190mm shaft length and a 220mm overall length. In the OP's photos, it looks like the seatpost is inserted far less than the recommended minimum 75mm-80mm.



There's an easy way to check out the crack: remove the seatpost and thoroughly clean out top of the seat tube to remove any crud or old grease. Take a hone and run it through the top end of the seat tube. If you don't have a hone, get some 100 grit or 120 grit abrasive cloth and either attach it to a wooden dowel or roll it up and rotate it inside the seat tube until you get a smooth finish. Do it with the bike standing up on end so that crud doesn't get down into the bottom bracket.

Shine a bright light into the seat tube to see if the crack is visible. Also does the crack continue around to the the split in the rear and stop or does it run below the end of the split? If so, it will continue to wrap around the tube.

There are some other important questions that everyone is assuming or guessing about: how much does belacqua weigh and their leg or inseam length. They could be a basketball player or a Clydesdale... What type of riding is he planning on doing besides "Want to use this for a winter beater."

Need more info rather than "Hey! Watch this!" and "Hold my beer!"

I've replaced one seat tube plus a frame builder friend has done a lot of those repairs so it's not an uncommon failure but can turn into a can of worms real quick.

verktyg

nomadmax 

I wouldn't ride it.

BFisher

I'd pass. Lots of great crack-free frames out there.

Vintage_Cyclist

Tough call.

Risk a catastrophic frame failure and steel tube impalement through your nether regions or just get another 30-40 year old, dime a dozen bike?

What to do, what to do?

repechage

With enough seatpost engagement, there won't be a catastrophic failure but, I bet it eventually gets very noisy, and that would bug me to no end.

forgot, I too am not a fan of those seat stay plugs, if a torch was to be taken to it, swap those out too for parts with more material.
would be sad to replace the tube then have one of those fracture.

The Golden Boy 

Nope.

Life's too short to ride bikes that try to kill you.

DMC707

IT is that simple. I wouldnt ride it - but a longer seatpost would probably unify it for a while -- the one you have in there is too short

If its a money thing there are lots of us on here who could probably donate a frame in etter condition to you for the cost of shipping --- i dont as most of my stock is size 53 or 54, but there are plenty of tall guys on the boards here

gaucho777 

I wouldn't, but I also don't expect a catastrophic failure.

An anecdotal side note: I have a bonded frame (carbon tubes, alloy lugs). The bond between the seat tube and BB came unglued. I didn't even realize what had happened for a couple hundred miles. What I eventually realized is that the bottom bracket would drop ~0.5-1 cm, causing ghost shifts with the front derailleur when pushing hard or out of the saddle due to under-BB cable routing getting extended. I suspect a failure with the OPs bike will have a similar feel once the crack eventually spreads.

+1 to too high seat post.

Gary12000 

I just fell in a parking lot at zero MPH on some fine sand/gravel the front tire slipped and i was clipped into cages.
after getting up and recovering my composure i carried on with the ride(s).. about a week later my hip swelled up like a tennis ball and it took two to three weeks to go down, i suspect a bone bruise, i will likely have issues with this for some time, but i am back riding 20 milers no big deal and not much pain at all.

I say all this to encourage rider safety, why take the chance you could really hurt yourself, if you have a frame builder locally and you love the bike spend the money.

i have a Trek 613 big man frame ill sell you cheap and you can switch all the equipment over and your back in business. its $75.00 plus shipping its got some rust on the stays is why its so cheap, but i ground the paint off and posted the pictures here and everyone said NBD, its just surface rust...

Gary

bamboobike4

I ride with wine a lot, so riding with crack, maybe.
Never tried it, heard a lot about it.