Bottom Bracket Getting Loose

[pete trials]

Hey guy, I'm really annoyed with my bottom bracket right know because everytime i'm riding it seems to come loose. I've titend it as much as it will tighten but it still comes loose everytime. Can someone help please?

[p_ruskin]

Mine does the exact same thing, haven't found anything to stop it yet :/

[Sponge]

Expensive option that *might* work is getting your BB threads chased and BB shell faced and then get a brand new BB that might have more suited tolerances for your frame.

Cheap way out is to just try some blue loctite. But it'll only work if you *completely* purge your threads on the BB and inside the BB shell of any grease or dirt. The loctite won't work if it gets in contact with any grease or dirt. Apply generously and screw it all together, let it dry for at least 24 hours. 48 just to make sure.

After that it should be fine. But be warned, it will take a bit of ooomph to untighten the BB in future if ever you need to.

Never use red loctite though. I made that mistake to a topcap bolt about 6 years ago, and long stong short: It got stuck and locked tight even though the bolt was turning and I had to hacksaw away at the topcap and stem to try and extract the bolt.

[liam n]

It got stuck and locked tight even though the bolt was turning

what do you meen, the threads were ripped?or the top cap got stuck to the stem? im confused

[craigjames]

I would imagine the inner silver section of the star nut came loose from the main bit and was spinning as he turned the bolt.

[liam n]

I would imagine the inner silver section of the star nut came loose from the main bit and was spinning as he turned the bolt.

ah i see, well surely there's more strength in a BB so it is less likely to break under the pressure of lock tite

[craigjames]

ah i see, well surely there's more strength in a BB so it is less likely to break under the pressure of lock tite

I think the point is that the bond between the two threaded parts is extremely strong, depending on the BB, if its faced etc the section where the BB tool inserts into can shear off.

[liam n]

I think the point is that the bond between the two threaded parts is extremely strong, depending on the BB, if its faced etc the section where the BB tool inserts into can shear off.

ah okay, i better keep my fingers crossed ,i used red loctite

[Sponge]

Nah,

What I meant was that the red loctite was so strong (studlock) that it basically stopped the bolt from screwing out whilst it was turning as it seemed the dried sleeves it formed inside the threads acted as a locking layer that just barred the bolt from turning itself upwards and outwards even though it spun. The silver bit in the starnut was dead tight when I finally got it all out.

But yeah, studlock (red) isn't recommended unless you want something to be pretty much permanently bonded.

Blue is the most commonly available one and more than enough so long as you prep the threads first and put a generous amount smothered all over.

[Krisboats]

Nah,

What I meant was that the red loctite was so strong (studlock) that it basically stopped the bolt from screwing out whilst it was turning as it seemed the dried sleeves it formed inside the threads acted as a locking layer that just barred the bolt from turning itself upwards and outwards even though it spun. The silver bit in the starnut was dead tight when I finally got it all out.

You've only got three options.

The centre of the star nut was spinning round as you tried to undo the bolt.

The head of the bolt snapped off.

You were hallucinating and only thought the bolt was turning when in fact it was staying still.

[craigjames]

That's what i thought, surely physics would dictate that if the threads are intact then the bolt must come upwards.

[Krisboats]

That's what i thought, surely physics would dictate that if the threads are intact then the bolt must come upwards.

I wouldn't even try to prove it through physics, common sense should be over-riding that need well before opening the textbooks.

[craigjames]

I wouldn't even try to prove it through physics, common sense should be over-riding that need well before opening the textbooks.

Fair point, simply put thread lock can't stop a freely rotating bolt screw out of a nut of some description if the threads are all ok.

When installing a BB, clean both the threads in the frame and the BB. Face the BB shell if required and chase the threads. Grease the threads. Put the non-drive cup in half way as a guide, screw in the drive side and torque up as specced, then tighten the non-drive up. Should be fine.

[terry_harris]

loctite works a treat mate