countalmaviva 

Folks,

Wiping down my 1986 Schwinn Cimarron today after a modest 70 mile loaded tour I noticed this:



Another clue: I've owed the bike since spring and sprayed Fluid Film inside. I began to notice the Fluid Film leaking and collecting at this spot. Along with this visible line, I'm pretty sure this must be a crack.

I don't notice any change in the performance yet. Any advice? Should I stop riding this bike? Ride with careful monitoring?

What's the likelihood of a viable repair?

Thanks,
Oliver H.

unterhausen

The crack goes along the shoreline of the bb shell to the right of your picture. You should look for the other end of the crack. It might be behind the crank, seat tubes usually break near the centerline along the side of the tube. The crack didn't originate on the shell. Given that it has propagated onto the shell, I imagine the back side of the seat tube doesn't look that great. Take the drive side crankarm off and take some more pictures. Kudos for cleaning your bike.

I don't think I would ride a loaded tour with your bike, but otherwise it doesn't seem like it would fail in a particularly dangerous way. I have experience with this sort of cracking due to my Teledyne titan. I regret wearing out a front derailleur before i noticed the crack.

Andrew R Stewart 

Agreed that the prognosis isn't good. A BB shell replacement is not an easy repair. One I would not consider. There are far more tour worthy bikes out there then tis one. And most are not broken. Andy

countalmaviva 

unterhausen , thanks for responding. I'm afraid you're right. It looks like there is a crack in the paint over most of the circumference of the ST where it enters the BB shell. I assume this would occur from the tube moving independently of the shell...?


NDS from rear

DS from rear

DS straight on

What would be the next step here? What would a framebuilder do to confirm damage? Removing the cartridge for an inside look seems like a smart idea. What about removing paint from the area?

I'm struggling to understand what is happening. Is it the case that the ST is still intact but just sliding within the BB shell? Or is the ST itself cracked?

Thanks,
Oliver H.

nomadmax 

Replacing a BB shell wasn't a big deal to Jack Trumbull of Franklin Frame in Ohio. He replaced this one and charged less than a hundred bucks labor.

David Tollefson

I had a previous year Cimarron that cracked in a similar fashion. That's a repair I wouldn't even attempt. But then again I don't build with lugs.

unterhausen

It looks like a faulty braze, and when it finally found a spot with decent brazing, the crack went into the bb shell. It's not long for this world.

The tube itself might be okay, hard to tell from here. Not sure that bike is worth the cost of a repair + powder.

repechage

Times best spent looking for another frame without issues.

countalmaviva 

nomadmax , thanks for the suggestion! I called Jack on Thursday, and, after sending photos, he's happy to do the repair. Interesting fact: he built frames for Steven Bilenky in the 80s! He echoed what Steven said to me once: younger framebuilders often are scared to do repairs. He gets a LOT of folks referring business to him. And I can understand the reluctance. Most of the time, anyone getting a frame repaired is sentimentally attached to the frame, so the stakes are higher. It costs your reputation. If you destroy a frame the customer hasn't even seen yet, well, it just costs money and time.

Thanks to all,
Oliver H.

unterhausen

This repair doesn't seem so bad. The problem with the repairs I have seen is that the builder screwed something up that I'm not going to be able to fix. Like the cracked head tube where the miters were clocked. Or the Waterford where they put the seat post slot too close to the seat stays. And they used silver, so it's a real pain to fix it right. There are tons of those bikes out there with cracks, just waiting for the owner to notice. So in that case, I would recommend someone else do it so I don't have to worry about it cracking again. If I had to do it, I would replace the seat stays entirely.

countalmaviva 

Thanks, unterhausen . I'm going to move ahead with the repair. This frame ticks all the boxes for me, and it was a long search to find it. Plus, after parting it out, I only have $75 in it. It's worth another few hundred bucks.

Cheers,
Oliver H.

apollodriver

omg - this looks very interesting - thanks for sharing this with us all

countalmaviva 

nomadmax I'd like to publicly thank you for bringing Jack Trumbull to my attention. My frame came back last week, and the repair is immaculate. I'm in business again!

Cheers,
Oliver H.

Andrew R Stewart 

Pretty quick turn around! Would you and/or Jack mind is we were told of the cost? Andy

countalmaviva 

Don't mind at all. The fee was exactly as he advertises on his website.

unterhausen

I want to replace the rear triangle on a bike, maybe I should go ahead and replace the Italian threaded bb shell while I'm at it.

bulgie 

There are also threaded inserts, Ital on the outside, Eng/ISO on the inside. Ceeway sells 'em. A marvel of machining, I can't imagine how they do it, with the right/drive side being left hand thread on the inside, RHT on the outside. I have some, can take a picture if anyone can't envision it, but in this case a picture is only worth maybe 30-40 words.

Mark B in Seattle

guy153

I guess you'd tap the thread on the inside first, with the outside still oversized, and then screw something in there to support it all while you cut the thread on the outside.

Sounds like a useful product. If you had a wrecked English BB you could tap it out to Italian and then use the inserts to get back to where you were.
​​​​

unterhausen

I don't order from Ceeway very often and last time I did, I forgot to order any inserts.

Two things occurred to me when I was out doing an errand. First is that having a single insert is a bit silly and invites problems because nobody makes shells by tapping from one side. So it should come in two parts. The other thing is that an English BB shell is not an unreasonable starting point to make an insert if a lathe that will cut Italian threads is available.