Bottom bracket falling out!

mr.b-campag

Built my winter hack up at the weekend. Fitted my bottom bracket - an italian threaded Record 9spd square taper - and rode to work this morning. On the way the bb almost completely unwound itself with the drive side going out and the non-drive side going into the shell. Presumably it's not possible to fit the cups on the wrong sides? I was fiddling around with the cups beforehand (I wanted to see if I could swap the italian cups to English ones and put it on another bike) but presumably if I'd put the English cups on by mistake it wouldn't have threaded in in the first place?

Anyone any ideas? It's not rideable as it stands as I think the cranks are about to fall off

ugo.santalucia

Suggest you re fit using a threadlock compound and torque the thing a bit harder than you did the first time.
Remove any dirt/grease/antiseize and clean the threads thoroughly. Apply threadlock then assemble and torque

nicklouse

Mr.B-Campag wrote:

(I wanted to see if I could swap the italian cups to English ones and put it on another bike) but presumably if I'd put the English cups on by mistake it wouldn't have threaded in in the first place?

nope you would not as one way the threads way too small to engage and the other the thread is so big it will not engage.

scroll down http://sheldonbrown.com/bbsize.html

mr.b-campag

Thanks gents. Will get hold of some threadlock (presumably bike shops have it?) and try again. But does your advice still hold given the further info below?

A bit of further info; when I put the italian cups back on the fixed one didn't go back on quite as far as it was originally, but I was hoping that when I fitted the bb it would push it on that last little bit (I didn't want to hit it too hard with the platic capped hammer I was using). When I fitted the bb yesterday the non-drive side was sticking out by what looked to be the same amount. When I tried tightening it further the axle in the bb would stop moving completely so I had to loosen it off. So this might stop me from tightening things up more.

nicklouse

why would you be using a hammer to put in something threaded?

is the frame new to you?

is this happening only when either "cup" is fully home?

sounds like new to you frame and the BB shell faces are distorting the BB.

what BB and crank set up?

keezx

nicklouse wrote:

what BB and crank set up?

Mr.B-Campag wrote:

Built my winter hack up at the weekend. Fitted my bottom bracket - an italian threaded Record 9spd square taper - and rode to work this morning. (

mr.b-campag

No it's not new to me. It's my old bike that I now use as a winter/trainer. It's a record square taper bb with italian thread (for my Simoncini frame). And no, I wasn't putting in the bb with a hammer!!! I had removed the fixed cup to see if I could convert it to an English thread (using a plastic tipped hammer and a vice) to use on my racing bike. That didn't work out too well so I put the italian thread back on, but like I said it didn't seem to go back on quite as far as it was on originally.

I couldn't screw both cups in fully, not least because as I got closer to them being fully in the spindle would stop rotating completely. This is a bb that hasn't seen that much use and has been sitting in a draw for a few years.

Really not sure what to do, so any help (and your earlier comments) much appreciated.

B

arlowood

My guess is that by removing the cups you have disturbed something internally that is now preventing them from fully tightening back into the BB shell without fouling up the spindle.

Just bite the bullet and buy a new BB. A Campag fit Tifosi BB is only £21 from Wiggle

http://www.wiggle.co.uk/tifosi-campagno ... m-bracket/

mr.b-campag

So is that it,case closed? If so, I suspect there will be a follow on about how to rebuild the bb properly at some point...:D thanks for everyone's input.

keezx

Mr.B-Campag wrote:

No it's not new to me. It's my old bike that I now use as a winter/trainer. It's a record square taper bb with italian thread (for my Simoncini frame). And no, I wasn't putting in the bb with a hammer!!! I had removed the fixed cup to see if I could convert it to an English thread (using a plastic tipped hammer and a vice) to use on my racing bike. That didn't work out too well so I put the italian thread back on, but like I said it didn't seem to go back on quite as far as it was on originally.
B

So you messed up the threads.....don't expect another BB to go in smooth...

mr.b-campag

So you messed up the threads.....don't expect another BB to go in smooth...

How did you come to this conclusion?

keezx

Mr.B-Campag wrote:

I had removed the fixed cup to see if I could convert it to an English thread (using a plastic tipped hammer and a vice) to use on my racing bike. That didn't work out too well so I put the italian thread back on, but like I said it didn't seem to go back on quite as far as it was on originally.

Well , I might have missed here someting, but I read it as if you did someting you better not do with bottom brackets.

mr.b-campag

Ah. As I said, I tapped the fixed italian cup off in a vice (with the threads suitably protected), found that the English one didn't go on as flush as it should (might try G clamps next time) so put the italian one back on but that didn't go back on totally flush either.
When I reinstalled it, it screwed in perfectly on the drive side, but not quite perfectly on the non-drive side: in the sense that it was sticking out a bit (by what looked to be the same amount that it wasn't flush by if that makes sense). Also, in tightening it up as much as possible the axle seized up so I loosed it off slightly. I should probably add (embarrasingly) that I put grease rather than thread lock on the threads which probably didn't help matters!

Anyway, I've now ordered a new daytona bb from halfords so hopefully that will sort it out (once you get a british cycling discount it is barely more expensive than a 3rd party one from Wiggle).

Hope that all makes sense!

B

keezx

Maybe your BB needs a good cleaning with a degreaser and steelbrush....
And measure the BB width , 68 is English and 70 is Italian (most)....

JayKosta

Do the non-working parts include a 'lock ring' for the non-drive adjustable cup?
If the non-drive cup just screws into the threaded BB shell, then there has to be something (e.g. the lock ring) to secure the cup so it does not move.

Usually the drive side 'fixed' cup is screwed fully and very tightly into the BB shell. Adjusting the non-drive cup is done to set the bearings so they run smoothly.

Jay Kosta
Endwell NY USA

keezx

Most likeley it wasn't a old skool BB but a semi"cartridge BB , not adjustable and no lockring , just screw in till it stucks.

Like this one:
http://www.racycles.com/products/detail/28840

mr.b-campag

Keezx has it right, it's like the one pictured in the link. I'm going to pick up a new bb this evening and try and fit it tomorrow (as my bike is still at work). Would still welcome thoughts on what to do with the old one. Should I just try a bit harder to squeeze the 'fixed' cup on?

keezx

Italian thread is notorious for coming loose on the DS.
As mentioned before, threadlock stuff (not too much if you want to loosen it ever!) and torquening to the max. recommended will do the job..

lapavoni10

I assume you fitted the fixed cup on the drive side?
Are you sure you have both Italian thread cups back on the bracket (English cups are slightly smaller).

When you re-assembled the cups, are the bearings now stiff?

mr.b-campag

Yep fixed cup defo on the drive side. Good point about whether I might have confused the non-fixed cups. I don't think so as it threaded in fine. Problem was it just kept going in...In any case I have just got a new Daytona italian bb so hoping to fit that tomorrow once I've removed all the gunk (and put some thread lock in).

Had no idea such loosening was an issue for Italian bbs. Glad I've got an English thread on my racing bike! I still need to fix the Record one (assuming I get this one fitted). Perhaps that is for another thread?

lapavoni10

Loosening isnt, had italian brackets on many bikes and never had an issue.
when its screwed in, the bearings are smooth? Wonder if the bearing is seized and undoing the cup.

cycleclinic

I use Italian thread BB's and never had one unwind, never used threadlock either. I torque them up to 60NM though to ensure the DS cup does not budge.

It will only unscrew if the threads are damaged, DS cup not done up tight enough or some other obvious problem.

If you dont't want that record BB send it to me as the bearing if worn are replacable.

mr.b-campag

OK new Centaur bb fitted and got home without any issues! Thanks for everyone's input.

B

andrew_s

Italian BB driveside cups are prone to coming loose because they are a regular right-hand thread, and the action of pedaling will loosen them if there's any trace of movement when you stomp on the pedals (see precession on wiki). English BBs are left-hand thread on the driveside, and tighten when pedaled on.
The right/left hand thread difference means there's no possibility of fitting an Italian BB in an English frame, or vice versa.

mr.b-campag

Thanks Andrew. Like I said, makes me glad I've got an English BB on my 'race' bike. I did the Italian one up pretty much as tight as I could, plus it has some thread lock on it so hopefully it will go through the winter ok.