Going Italian - B/B repair?

[David9694]

I’ve got a couple of frames with jiggered b/b BSA threads in which I’m running the square taper threadless b/bs - these seem to work fine, the first one tried to come undone but has settled down. You do need the two Shimano tools to nip it up tight and thread locker presumably helps.

I’m getting interested in going Italian and making a proper repair. I’ve got the Lifeline/ X tools BSA facing and tapping set, but and others have looked, no Italian taps seem to be available for it, so it would be off to Germany for Cyclus, @ £94.35.

I run a Viner frame with Italian threads with Shimano 105 and the extra shell width doesn’t seem to make any difference.

There’s a difference between cleaning existing, cutting Larger new from jiggered old and threading a new b/b shell? How simple is it? Do I just run it in, cutting oil, half a turn in, a quarter back, (it sounds like it’s a two person job to get it started) and job done, bellisimo?

Finally, what do they do in Italy?

[Brucey]

there are loads of ways of fixing a knackered BB of which Italian BB threading is just one. It isn't a 'proper repair' per se, it is arguably just another bodge. If you are going to do it then the best and easiest thing is to take it to a LBS/framebuilder with the correct tools and let them do it.


FWIW as an engineering approach having two RH threads in the BB shell is a bit crap really.

Note also that if you have already run a theadless BB and it has worked loose, it may already be too late; there is only a few thousandths difference in the diameter of the Italian and BSC threads (if the BSC thread is completely stripped you probably don't get a full thread form when tapping out to Italian anyway) and you may already have used up the available leeway.

cheers

[Polisman]

Another option the venerable Mavic SSC bottom bracket, which is virtually indestructible and requires no threads on either side at all...

[Mick F]

How is it secured if it has no threads?

[hamster]

Tapered lockrings.

[Mick F]

Tapered lockrings?
Steel lockrings hopefully and with a nice long shallow taper.

Do they still make these things?
If they're so good and you don't need threadings, why aren't all ST BBs like that?
Why go to the trouble of (expensive and accurate) threads?

[fastpedaller]

I had a Mavic threadless many years ago - The bb shell has to be prepared with a tapered cutter on both sides (mavic tool) similar to face cutter but with addition of the taper. The aluminium alloy cartridge is similar to commonly used ST type, but is threaded both sides. Threaded aluminium rings (with matching taper and tapered nylon 'washers') hold it all in place. It worked for maybe 15 years of no maintenance, but when I eventually removed it there was a lot of corrosion, and it took some effort
Still not as good (IMHO) as a good fitting original thread ST bb (cartridge or loose)

[colin54]

An article on the evolution of Mavic bottom brackets here with good pictures of the taper set up towards the end .

http://lecycleur.com/parts/mavic-bottom-bracket/

[Mick F]

Thanks Colin.
Very interesting.

[Polisman]

These Mavic brackets are famous for their longevity. The seals are excellent and the materials top notch. I bought a few twenty odd years ago and they are both still running without a single issue. The faces of the bottom bracket can me prepared with a simple angle grinder. Not as pretty as the original tool, but works all the same.

Not for nothing were these known in the trade as 'frame savers'.

[Brucey]

little-known feature of Mavic BBs; the spindle in them (at least the ones I had) was cross-drilled, so, using a grease gun, you could pump them full of fresh grease via the crankbolt hole.

cheers

[LinusR]

FWIW as an engineering approach having two RH threads in the BB shell is a bit crap really.

It is. The Italian threaded bottom bracket on my steel Pinarello once came unscrewed as I was happily cycling along.

[Gattonero]

FWIW as an engineering approach having two RH threads in the BB shell is a bit crap really.

It is. The Italian threaded bottom bracket on my steel Pinarello once came unscrewed as I was happily cycling along.

If was that crap, there would be milions of italian cyclists lost up in the mountains

Surely, the drive side thread ought to be a left-hand one, but as long as you have the BB shell theads done properly in the first place (most manufacturers make them a bit slack, to make easy for "fatory bike build") and correctly tightened, the BB will not come undone.
I've sorted hundreds of people that kepts on having their BB undone, when not properly installed.

[Gattonero]

I’ve got a couple of frames with jiggered b/b BSA threads in which I’m running the square taper threadless b/bs - these seem to work fine, the first one tried to come undone but has settled down. You do need the two Shimano tools to nip it up tight and thread locker presumably helps.

I’m getting interested in going Italian and making a proper repair. I’ve got the Lifeline/ X tools BSA facing and tapping set, but and others have looked, no Italian taps seem to be available for it, so it would be off to Germany for Cyclus, @ £94.35.

I run a Viner frame with Italian threads with Shimano 105 and the extra shell width doesn’t seem to make any difference.

There’s a difference between cleaning existing, cutting Larger new from jiggered old and threading a new b/b shell? How simple is it? Do I just run it in, cutting oil, half a turn in, a quarter back, (it sounds like it’s a two person job to get it started) and job done, bellisimo?

Finally, what do they do in Italy?

If your BB shell is stretched so that the threads won't hold, the only long-term solution is to have it sorted by a frame shop: they will cut along the BB shell, squeeze it and braze it again, proper cutting taps will be run in then.
Just check the threads with a decent BB unit, like a Shimano UN55/54 and see how much play you get on the threads.
Consumer-type taps are not meant to cut threads, they're too wide and there will be a lot of friction. Plus it's pretty bad to cut a 36mm thread in a shell that was meant to have a 34.7mm one and is already stretched!

[Polisman]

little-known feature of Mavic BBs; the spindle in them (at least the ones I had) was cross-drilled, so, using a grease gun, you could pump them full of fresh grease via the crankbolt hole.

cheers

Not such a little known feature. I remember back in the 90's a stream of cyclists coming into our lbs as winter approached to do this very thing. Been doing the same to my own small supply once a year. I've been using a Mavic bracket in a commuter bike with a very dodgy thread, and nearly 30 years solid use, not even a murmur from it