Bicycle Mechanics - Italian bottom bracket problems: myth or fact

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.
Fat Hack
06-30-04, 07:22 AM
Before you complain, I've searched the forums, but I still need some clarification.
Are Italian threaded bottom brackets (being right-hand threaded on both sides)
much more likely to work loose, or has this problem (or myth) been rectified
since one-piece BBs became ubiquitous?
Some people suggest using Loctite, but how does this idea "gel" with the suggestion
that you must grease the BB threads to avoid seizing due to corrosion?
Should I grease the start of thread then Loctite the end?
Thanks :)
Yes avoid It threaded if you can. they suck, they come loose. The loctite at the end sounds like a good idea.
A well tightenned italian bracket will not easily come loose. Never use locktight on bottom bracket threading. It will make impossible the removing of cups.
Seaners
07-01-04, 02:28 PM
Well tightened being the important phrase here. I had loosening problems on mine, a Basso frme with a Campag *** style sealed BB (non-splined). I originally installed it with a tool that looked kind of like an old type right hand cup remover but with a short (approx 150mm) handle. Dang thing came loose a couple of times even with loctite. Maybe I didn't use enough. But I went to the suppliers who gave me a tool that slid over the BB from the side and grabbed it, that had flats to attach a big mo-fo adjustable wrench. No problems since.
Before you complain, I've searched the forums, but I still need some clarification.
Are Italian threaded bottom brackets (being right-hand threaded on both sides)
much more likely to work loose, or has this problem (or myth)
I'm no mechanic, but...........
I have heard that the problem has improved since one-piece BBs came in, partly due to the better tools we have to put them on with these days.
The clockwise thread on the drive side is a modest manufacturing cost-saver and a significant engineering blunder. The French belatedly figured this out in the late 1970s, when Motobecane, and then Peugeot, switched over to Swiss threading.
I ALWAYS use BLUE (soft-setting) LocTite on my two self-loosening BBs: the UO-8 and the Bianchi. Neither has given me any trouble, but the BBs on my previous Bianchi and Peugeot DID come loose a couple of times while I rode. Fortunately, the Capo and the Schwinn are English/ISO-threaded, and the PKN-10 is Swiss-threaded.
Having said all that, cartridge bearings should ameliorate the situation by eliminating the direct epicyclic action of the ball bearings against the cup. Also, the one good thing I can say for French or Italian BB threading is that one can microadjust the chainline by using an adjustable cup and lockring on the drive side, as well as on the left.
Fat Hack
07-02-04, 11:49 AM
Having said all that, cartridge bearings should ameliorate the situation by eliminating the direct epicyclic action of the ball bearings against the cup.
BINGO! That's what I was looking for; some reassuring logic. :)
thanks
Barnaby
07-02-04, 12:31 PM
The clockwise thread on the drive side is a modest manufacturing cost-saver and a significant engineering blunder. The French belatedly figured this out in the late 1970s, when Motobecane, and then Peugeot, switched over to Swiss threading.
I ALWAYS use BLUE (soft-setting) LocTite on my two self-loosening BBs: the UO-8 and the Bianchi. Neither has given me any trouble, but the BBs on my previous Bianchi and Peugeot DID come loose a couple of times while I rode. Fortunately, the Capo and the Schwinn are English/ISO-threaded, and the PKN-10 is Swiss-threaded.
Having said all that, cartridge bearings should ameliorate the situation by eliminating the direct epicyclic action of the ball bearings against the cup. Also, the one good thing I can say for French or Italian BB threading is that one can microadjust the chainline by using an adjustable cup and lockring on the drive side, as well as on the left.
John E-We corresponded on this topic some time ago. My Concorde has an It. BB. and is prone to loosening. I think that the problem now is compounded by the fact that the alloy holes that the tapered ends come through on the cups have been damaged by the loosening action over the years. I am now about to order a new BB, and was going towards Phil Woods. I would order to the exact spindle length of the present Edco BB, and I think they have one that has a right offset to match the present specs. Will the Phil Woods BB help to solve the loosenig problem by the nature of the ring method, or are the rings that Phil Woods uses just adjustable cups in another form?
I notice tha Phil Woods recommends blue loctite for the installation of their BB's in frames of certain materials. I had a loosening problem prior to loctite on the drive side only, and used blue on that side and tightened heavily. It did not come loose. But, since going fixed with this bike, I had loosening on the left side.
You are correct on the value of micro-adjusting of the right side on Italian BB's. On mine I moved the BB way to the left to get a proper chainline. Possibly the loosening of the left side cup had to do with the reverse speed tempering of the crank pedal action in braking effect, I do not know, but it seems to me that fixed riding must put more stress on the BB in general than non-fixed riding.
Poguemahone
07-02-04, 03:32 PM
I use a Var 30 fixed cup tool for the fixed cups on my French bikes, tightening the cup down hard. No loctite. Works like a charm, never had one work loose. The tool provides a lot of extra leverage. Worth it, if you work on these bikes with any consistency.
Fat Hack
07-02-04, 09:36 PM
So, what about the standard advice that suggests greasing the cups to prevent the BB "fusing" to the frame should any corrosion occur?
I've been waiting for a consensus on this thread before I put the BB in.
I've got the wrench in my hand right now :)
miamijim
07-08-04, 07:30 AM
Fat Hack loctite will isolate the metal surfaces from one another. If your frame has Italian threads you dont have much of a choice. install it. if it loosens tighten it more than you did the previous time.
Fat Hack
07-08-04, 07:40 AM
Thanks
I only just put it in yesterday, and have ridden it once, and so far so good.
I chose to grease it to see what happens, but I did it up as tight as I could using a 12 inch wrench.
This can be an experiment for us all ( :D ), so I'll post the results.
I used red 242 loctite on my old Italian frames, but I found it aggravated the problem because the loctite is chalky when it cures and as it breaks it becomes a powder that reduces the friction the threads provide to hold the bb in. I did use the blue 262 in small dabs on the thread to prevent a loosening problem I was having- removal wasn't that hard either; just needed a good tool, good leverage and a firm snap to it. Make sure the threads are completely clean 1st.
Now, I must qualify this by saying I never had a BB seize up on me though I never used exotic materials, so my experience might not apply there.
OneTinSloth
07-08-04, 11:56 PM
i have two italian threaded bottom brackets right now, been riding one for 3 years, and the other for a little over a year and neither have ever come loose. they're both cartridge bearing bottom brackets. on one frame, i used the neon green shimano grease, and on the other in used this old, sort of shimmery silver anti-sieze compound. the anti-sieze stuff is superb, although i'm not sure it's made anymore. the grease has me a little concerned as i've seen even very well-greased seat posts/tubes fuse together after enough boston winters, and neglect...some day i'll pull it out and see for myself...
Fat Hack
07-09-04, 12:38 AM
Thanks all, again :)
Fat Hack
07-09-04, 12:39 AM
the grease has me a little concerned as i've seen even very well-greased seat posts/tubes fuse together after enough boston winters, and neglect...some day i'll pull it out and see for myself...
wow! :eek:
socalrider
04-29-05, 07:35 PM
Both my Merckx's bikes are Italian threaded and they have come loose in the past.. I would not recommend loctite but make sure that you tighten them very firmly..
Yes avoid It threaded if you can. they suck, they come loose. The loctite at the end sounds like a good idea.they don't come loose if properly tightened. I got about a dozen of them ...No issues, since I learned about the self loosening aspect and started tightening them properly.
Having said all that, cartridge bearings should ameliorate the situation by eliminating the direct epicyclic action of the ball bearings against the cup. It doesn't..I had cartridge types come loose till I learned to tighten them properly.
Retro Grouch
04-30-05, 12:01 AM
It doesn't..I had cartridge types come loose till I learned to tighten them properly.
The torque spec for bottom brackets is usually around 30 to 35 ft/lbs. That's a pretty good amount. It's more than I would have used if left to my own judgement. Judging from the majority of bikes that I've worked on, it's more than most other mechanics use when left to their own judgement too. Bottom brackets are one of three places on a bicycle where I use a torque wrench.
The torque spec for bottom brackets is usually around 30 to 35 ft/lbs. ... Bottom brackets are one of three places on a bicycle where I use a torque wrench.
Good advice, RG, and thanks for the spec. I suspect that English or Swiss fixed cups do not need to be torqued as firmly as French or Italian. I still vote for blue LocTite on French or Italian fixed cups, but I realize this is controversial. I haven't had a loose BB cup on either the UO-8 or the Bianchi in years, so I must be doing something right (for a change).
Powered by vBulletin® Version 4.1.12 Copyright © 2012 vBulletin Solutions, Inc. All rights reserved.