jdawginsc 

Ok...on a bargain Faggin from Italy...everything was cleaned and beautiful until I went to install an Ultegra 6500 BB.

Firstly, I know the threads are Italian for both the BB and the shell. My handy slotted thread cleaner (Italian) was able to hand thread all the way into the shell on both sides.

Individually the cup/cartridge side and the ND side cups both will thread in. However, when I try to thread both in (to fully install), there is a problem Houston. It doesn't connect and the threading stops, obviously. Example, I thread the drive side in, and the non-drive cup stops because it doesn't align with the spindle. I tried doing it the reverse way, and the same happens. I even tried doing it on each side...Nope.

Can I assume somehow the stell BB shell twisted in a way that the two threaded sides no longer align? Or am I missing something obvious. Do I need to go to a normal cup and bearing set up and forget the lovely 7700 octalink crank and BB?

madpogue 

If not twisted, maybe the threads on the two sides just weren't cut perfectly in line with one another, and the original cup/cone/axle BB was able to "tolerate" the misalignment. Just a WAG.

3alarmer 

...I've worked on a lot of old bikes, and thankfully I've never run into one where the BB shell was "twisted". What I have encountered on a few olde steel hand made bikes is a seat tube end that projects far enough down into the BB shell that it allowed for assembly with a regular old school BB spindle with cups and bearings, but did not give enough clearance for installation of a cartridge BB, which is considerably fatter in diameter. Check with a light, and feel around in there. It's kind of a tedious job to file down the end that's porjecting in there if that's what you got, but it's doable if you absolutely have to have that BB.

miamijim

Alternate installation...start the adjusting cup then install cartridge. Go back and forth but make sure the cartridge fully seats before the adjusting cup.

Sometimes cartridges will hit an internal obstruction like a bb cable guide bolt.

Prowler 

+1. I had this once. Check that bolt or plastic pin. Allowed Cartridge to thread in but cocked it a couple of degrees. Enough that the NDS cup would not engage.

madpogue 

D'OH, This! Totally forgot, I have experienced this, now that I'm reminded. You can thread in the cartridge, but the screw protruding into the shell is enough to "offset" the cartridge, and make the other "cup" not line up. Back out that screw and see what happens. Then you just have to file/cut down that screw.

dedhed

I also had the issue once on a Koga-Miyata where the generator internal light wiring wouldn't let the new cartridge install properly.

jdawginsc 

Good suggestions! Will check that.

jdawginsc 

This is a really good possibility. I ran my finger through it and there is very little protrusion, but it might be enough that it is pushing the cartridge down, not allowing the spindle to engage the other cup's opening. Looks like that is my first option. If not, we go to the non-7700 cartridge and crank option options.

mpetry912 

I'm betting it's the cable guide bolt under the BB shell as others have pointed out above

just loosen it and back it out a couple turns, install your BB, and then re-tighten

Mark Petry
Bainbridge Island, WA USA

madpogue 

^^^^ I've encountered several cartridge BBs with dents in the outer casing, from just this process. There's probably plenty of room inside the cartridge for it to withstand being dented by tightening the screw. But rather than chance it, or create the "collision" between the screw and the cartridge body, I'd prefer to cut the screw. It's effectively a sheet metal screw, after all, not a bolt. It only needs to be as long as the thickness of the shell.

jdawginsc 

It's a braze on cable guide, so not that.

madpogue 

So if it turns out to be the bottom end of the seat tube projecting into the shell space, a Dremel with a barrel stone might be your friend.

Spaghetti Legs 

I would get the bottom bracket shell chased. I had the same problem with a NOS Cinelli Supercorsa. Cartridge BB would bind up when I installed, a problem I’d never run across. After some back and forth here about “is this a defective frameset?” I got it chased and everything is fine.

speedevil 

Cup and cone BBs will tolerate slight misalignment better than cartridge BBs. Since you've already checked the threads, and have by now made sure there isn't an obstruction that is pushing the cartridge a couple of degrees off, the next step is to have the BB shell faced.

A true bike shop (note: not just a bike assembly shop) will probably have a BB shell facing tool that can ensure that the faces are parallel with each other. For older frames that had cup and cone BBs, this wasn't a critical step, but with cartridge BBs the shell faces do need to be parallel to avoid misalignment.

JohnDThompson 

Make sure you use a piloted tap set to do this, to ensure that the threads on each side are co-axial.

Johno59

Make sure the threads are clean. Work in both sides simultaneously. Take it nice and slow when the two sides begin to mesh.
If no luck get a proper BB with cups, an axle and ball bearings - that should last 40 years or so.

miamijim

So take a Sharpie or other similar marking device and ‘mark up’ the cartridge real good. Install as best possible and remove. Check cartridge for marks. Marks indicate obstruction,

jdawginsc 

Thanks all. I will follow all of the suggestions until I figure that little guy out.

repechage

Or, ditch that and buy an Edco eccentric lock bottom bracket. No worthwhile threads required.

jdawginsc 

Sooo....after cleaning threads and using my little slotted cup tool, I was able to thread it all the way in, then another 1/4 inch or more. So I don't think it is binding on anything.

I think it is that the threads on each side are misaligned with the other side. A cartridge bearing has little fleexibility in aligning with the cup on the other side, so I imagine they must have used cup and bearings with a free spindle...I also imagine it must have binded a bid.

I guess I need to get the threads re-cut, face and chase.

madpogue 

Why not revert to cup & cone?

3alarmer 

.
...most of these threads are originally cut with piloted taps (there's a pilot pin aligning both sides as they go in, cutting the threads). I've never actually encountered one where the threads were misaligned from one side to the other, but I'm sure it's possible. (From a things wrong with old bike frames perspective, all things are possible.)

Anyway, I'm only chiming in to say you need to be pretty careful "recutting" Italian threads, because you're already at the largest inner BB diameter for threads, so if you **** up, you can't just bore it out and recut it Venusian, or something else. There are a number of those expanding "threadless" cartridge units, but I don't know of any that will work with an Ocatalink crank. If it makes you feel any better, yesterday I was drilling and retapping a rear dropout on a frame that came to me with one of the holes plugged with the remains of a frozen adjuster screw. It was late, and instead of leaving it until today, I went ahead and snapped off part of the tap in there. I just filed it flat and went with one of those clamp in adjusters on that side.

Sometimes, despite your best intentions, you just have to go with a workaround if you want to ride the bike.

repechage

I have, actually not that uncommon, but in the traditional assembly era misalignment was tolerated.
The chances of using a piloted set of taps, Campagnolo, Cobra, or of similar design might work, but the threaded cartridge parts will be of loose fit.
Edco, eccentric locking.

repechage

no, they are not originally cut with piloted taps, (too slow) there is indeed alignment in the virgin part, but distortion in the framebuilding process is not that hard to occur.