Italian bottom bracket loosening.

[onlyhuman]

I had read this was a recognised problem and today it happened, the right hand (drive side) bottom bracket locknut loosened. I noticed a squeak under heavy load, and then saw the nut was loosened right off. Tightened it up with a borrowed hammer and a piece of wood to get home.

How do you suggest I address the problem? What tools are essential? I have some of the c-shaped locknut spanners, just basic ones. Is there anything I need to know about Campagnolo BBs?

 

[accountantpete]

Depends what Campag BB you have and how old it is- they were buggers for changing the design - but basically you need a specific tool to do the job which might be something like this one

http://www.pedalon.co.uk/acatalog/park_campagnolo_bb_tool.html

Are you sure it's an Italian threaded BB?

 

[onlyhuman]

I'm not an expert. It's not a cartridge BB, I was told it is an Italian BB, it is a Fondriest (Italian) bike I think from 1994, and the BB locknut tightens clockwise.

 

[accountantpete]

I'd have a look through Sheldon's pages starting with this page

http://www.sheldonbrown.com/tooltips/bbcups.html

or you could upload a photo.

 

[swee'pea99]

I used a big screwdriver and a bloody big hammer, but then I'm a bit of a sophisticate.

 

[GrasB]

Anti-vibration thread glue, not the permanent stuff I've had to junk frames over that stuff. The milder ones give enough resistance to kill creep but can be undone with reasonable but high verging on slightly excessive force depending on how good your chosen thread glue is.

 

[Radius]

^^ +1

There's a version of Loctite that fits exactly this description, and I used it on a LH crank bolt after it kept working lose. Hasn't moved since.

 

[Steve Austin]

Loctite threadlocker BLUE works a treat and comes undone when you need it to

 

[Jonathan M]

Isn't this the reason that "english" threaded BB's came around, to stop the right hand cup loosening when riddden?

 

[accountantpete]

Isn't this the reason that "english" threaded BB's came around, to stop the right hand cup loosening when riddden?

yes - the only problem is that English BB's can be very difficult to unscrew. So it's swings and roundabouts.

 

[MartinC]

Sounds like it's an old fashioned cup and cone BB in an Italian shell. If the threads are a sloppy fit they can unscrew. In my experience this doesn't happem if they're done up tightly enough.

You need to put some threadlock (Loctite 222 is the right stuff, blue will be OK too) on the threads and do it up tightly with a proper fixed cup spanner. You'll need to remove the crank to do this and loosen off the adjustable cup first (C spanner and a peg spanner).

You'll need to adjust it again afterwards (spinning freely with no play at all at the spindle). The trick is in knowing how much the preload on the bearings will back off when you tighten the lockring - you'll have it adjusted just right and then locking it up will generate some play.

Doing this without the proper BB spanners is difficult and damages the BB, paintwork and your knuckles!

An old Athena double chainset will fit a modern Campag 111mm cartridge bracket. They're still easy to obtain. Mirage has steel cups. Veloce has Alloy cups and the Centaur one has alloy cups and a hollow axle too. These are much easier to fit and have less tendency to undo. The Tacx tools (FAG type for Mirage and Veloce and the Record type for the Centaur) are the best because they lock onto the spindle and can't slip off.