SteelCharlie

Do NOT let the boys and girls at any bike shop use any tool that removes metal on your bike. Taps, reamers, facers, etc are precision tools that that can be destroyed and destroy what they are used on in a heartbeat. Find an ADULT, no matter what age, that actually knows how to use the tools and has well maintained and quality tools. There is prolly no more important part of the bike than the BB where that is an absolute necessity! And Italian is as big as it gets - you screw that up and there is no place to go. High quality, piloted taps and facing tools are nothing less than essential to attend to a BB.BTW - the threads on the cups in the pix are filthy. Properly cleaning them and the threads in the shell may be all you need. Why are you working on a high $ bike of you don't know what you're doing? Just curious, ya know?

onespeedbiker

First a couple of clarifications; you show the non-drive cup partially threaded, so I assume your threading issue is with this cup. Do you any trouble threading in the drive side cartridge? I'm betting the non-drive side threaded cup has some cross threading (as it is the only part of the BB/shell that is aluminum). In order to track down the problem, you should try threading the fixed side cartridge into the non-drive side (assuming it threads in the drive side without a problem); my guess is it will thread in no problem, which points to the non drive threaded cup as the problem (you may be able to thread the cartridge all the way through from one side to the other as Italian BB shells are often cut this way; regardless, there is certainly no reason to chase the shell threads if the BB threads in easily on both sides). If this is the case, check the threads on the non drive threaded cup; again I'm guessing there is crossing threading at the beginning (it may be hard to see). The problem with using the driveside lock ring to clean up the threads on the cup, is the ring will most likely follow the cross threading, but it will work on the cartridge threads. Below is a method to fix the problem if it's the non drive threaded cup, however it uses the BB shell to fix the cross threading. It would be better to either try and purchase a new non drive threaded cup or use a lesser bike to clean up the cup's threading.

The way I have solved this is to carefully thread non drive threaded cup in the shell, if the cup is cross threaded, it will not thread in evenly and instead cant to one side as it picks up the cross threading; there will be a high side and a low side. Loosen the ring slightly, and give it a tap to the high side with a hammer so the ring is square with the shell. Continue threading in the cup and if the ring starts to cant again, realign the ring with another tap; repeat until the ring threads in square (it is unlikely the cross threading is beyond the first couple of threads). You will probably have to use a tool for threading, but the amount of force will not be much; if the force ramps up at all, stop and evaluate.

MarkusForest

I partly agree with you on trusting such an important job to just any LBS. Will ask around the local bike clubs for references. Also, I will most definitely clean the hell out of all parts involved.

As for what i am doing working on a high $ bike? It is a hobby. I am computer guy by profession. Researching and getting my hands dirty is relaxing to me. This issue, as frustrating as it is ..... is still fun. Every issue I have is a learning experience.

Thanks for you input and time on this.

MarkusForest

The first image is of the drive side, unless I am reading your note above wrong. I have trouble threading both sides of the cups. Also, I tried treading back in the old BB and it wouldnt go in smoothly at all. Seemed a bit easier than the new campy one. Although, I didnt completely thread in the old BB.

wrk101

Give the OP a break. Even a high dollar bike is a relatively cheap item compared to a lot of stuff. My dad spent more on a set of golf clubs than I paid for my Colnago. Sure, I have made some regrettable mistakes over the years on bikes.

Good move #1 : He is seeking advice before forcing parts.

Next step: find a good shop that you trust. I like smaller shops, where the owner is often the mechanic as well. Talk to the mechanic, does he appreciate older bikes? I talked to the head mechanic at a LBS here about my 1987 bike. He told me it was NOT worth working on, as any bike over five years old was obsolete anyway. Enough said, crossed them off my list. "I've never seen one of those" is another quote from bike hell. Do they have good, specialty bike tools, or do you just see the basics?

As an old gray hair myself, gray hair gets BONUS points. "How long have you been working on bikes?"

Katiesmalls

Just for my own knowledge and experience, hoping I can learn something, How does the Campy crank arms fit on the DA spindle. Do they slide onto about the same area where the DA sat? Or anyone else that has experience with this particular match up, How does the taper of Campy compare to DA, can you just slide one on the other w/o removing BB and expect arms to sit in alignment the place they need to be on the frame
Thanks

MarkusForest

This is the reason i switched from DA BB (111mm?) to Campy BB (103mm?). I was hoping i could simply remove DA cranks and add campy cranks (both about the same vintage). I found the campy cranks stuck out too far, whereas the FD couldn't be used. Whether this has something to do with the form factors of the cranks or the taper of the spindle, I have no idea.

Check back here to see my updates. Although I will not be looking at the problem again for about a week.

Pars 

Katiesmalls: ISO and JIS spindle tapers have been discussed a lot on this forum. Campy is ISO (or near-ISO) while Shimano is JIS. Square Taper Bottom Bracket Interchangeability

I would agree that the first step would be a good cleaning of both the cup threads and the BB threads. One useful trick to ensure you do not cross thread is to begin by turning the cup backwards. It should "drop" into the thread at some point, where you can then reverse to the appropriate tightening direction. If the BB threads are already cross-threaded, this might not help much. Close examination of the threads might show signs of cross threading?

onespeedbiker

My bad, my brain got turned around thinking the cup when on the non-drive side. Regardless most of what I said still applies, just move the cup instructions to the right side. Could you take a photo of the ends of the cup threads?

Last ride 76 

That your DA bb doesn't go back in smoothly says
1) Dirty threads
or
2) The machining of the threads was not sufficiently similar
or
3) There has been some cross threading.

So, like others have said, Clean everything WELL, then try to put the DA parts back in. If that goes smoothly, try the DA lock ring on the Campy threads. If that works, you should be golden.

If any of these steps don't work smoothly enough for your comfort, get it chased and faced, by someone who has some experience and is comfortable working on steel frames.
It's not rocket science, but it does require skill. (or luck)

Katiesmalls

Hi, haven't played around with Bottom Brackets for a while since I retired. All I can say is there is always some difficulty for the most part. Can you " CLEAN " the threads on the fixed side by screwing another cup, even the one that holds the lock ring, just to re-CUT the threads. If the op can get the new fixed cup seated, with a little force, and as long as it doesn't cross thread, it will be in there for the next 100 years. Ive changed many bottom brackets in almost 40 years of playing with bikes. The BB area is always an Achiles heal. Similar to trying to get a frayed cable end ( the only cable you have long enough ) through the little grommet/nub on the rear derailleur, ( then you finally get it through and realize you missed a clamp stop (LOL) When I worked in the shop if the cup screwed in straight to the BB or any male/female threading for that matter, and we knew it was very similar, we marched forward. Again though, free internet advice is exactly that. I hang out now,chatting, helping out here and there at local shops, and I can pretty much state, very very very few shops have the expertise to clean, ream out, and thread a Itailian bottom bracket. This is just my observation, I am sure there are many competent people out there, but most shops just hire a young person to assemble, tune up and hang parts on frames, while learning on the job. Nothing wrong with that, thats how I learned. For most shops this is not profitable, when they can sell you a new bike. I recently brought in a Park tool I have, the bottom bracket pulley crank arm remover, to a shop where I was gonna hang out and help while working for some parts. The shop owner told me ( as I bring my own tools ) he never saw the park tool that had two different sized threads to match different size crank arms on one tool. Simply taking off the male insertion side and flipping it over. I never saw one that didn't. Anyway, ON ANOTHER TOPIC, I posted a new thread of Mavic SSC rims I just received. I think anyone into CV stuff would enjoy the pics. They are truly rare of the rare, I don't know if they were actually ridden by Hinault, but they were the team issue on the support car. I am very proud of them and it took me a long time to get from Belgium, so I am kinda boasting.
TO ALL HAVE A SAFE FUN HAPPY NEW YEAR
( Just pulled out of my drawer a campy GS bottom bracket. It would not thread into the BB shell tha a Record Campy BB came out of. Couldn't even begin to catch the threads on the first turn properly. So in that case a Shimano BB cup went in and I just worked with the front derailleur adjusting it to the way the crank sat on it. Sometimes it just goes that way, and things for whatever reason don't line up, and if you don't have a store full of parts, you go to plan B )

MarkusForest

Update and closure

After Fully cleaning all threads involved, applying a little oil and applying pressure, the BB went in smooth.

My problem was I was not applying enough pressure. I was working on my 80s Italian made Bianchi Celeste a month ago and the BB turned in by hand to about 80%. Meanwhile the Colnago BB could only hand turn to about 10%.

Thank you all for your time and support on this.

M