Extended crank set keeps slowly unscrewing no matter what I do, causing wobble and looseness in the pedals.

[Deliveryfoot]

Jul 21 2012 UPDATE!:

Took apart the cup. Turns out the issue was crushed bearings cartridge on the drive side. I dont know the name, but its a light piece of metal that holds the bearings in a circle.

I'm only here to point this out before i forget to entirely. I'll try and let others know if its because i put the bearings in backwards or not. Or if its just because i tightened too much.

---

2nd update:





It's hard to see, but it seems the bearings are digging into the shaft itself. Creating a pit and valley. I use the lowest gear possible, but i do a lot of hard and heavy pedaling from a dead stop, especially uphill. I bought a spare crank set expecting the worst and luckily it paid off. So i replaced nearly everything. The cups inside seemed perfectly fine.

I took the advice of park tools here and pulled the bearings from the cage and shoved them in with grease like in the video

And as i began testing new parts, put it through a bit of a torture test, though no different from if i had to pedal on an inclide at a dead stop and it immediately began "loosening". And my understanding is such, the shaft is cheap chinesium and is pitting under the pressure of the bearings from the strenuous pedaling.

Please, if anyone can recommend a good website where i can buy a new high quality extended crank set in canada, please let me know!

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This is my latest attempt to get it to stop. I put small metal rod between the 3rd screw inlet and even used marine JB weld to possibly seize it all up. Cleared the threads of grease and soaked in blue lock tite and cured for 24 hours.

After 5 minutes of pedaling, the crank went from firm to ever so slightly wobbly. I am certain it will continuously unwind like it did before. If not, the wire will jam it up and leave me with some annoying amount of wobble.

The threads here are both "right-tight". Even the smaller "lock nut" i am sure that's not right, but it was the only way it would thread on.

 

[Sidewinder Jerry]

Never had this kind of problem with The Staton Inc bottom bracket used for the Staton Inc triple chainring shift kit. Now, in the shift kit one of the two White Industries Trails freewheel cover did want to work it's way loose, so I used Vibra-Tite to fix the problem.

 

[Sidewinder Jerry]

You may want to try this Lock-Tite, expensive but I've never seen it broken.

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[Deliveryfoot]

You may want to try this Lock-Tite, expensive but I've never seen it broken.

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Find many great new & used options and get the best deals for Vibra-TITE 137 Permanent High Temperature and High Strength Anaerobic Threadlock at the best online prices at eBay! Free shipping for many products!

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I thought briefly. But i know i'll never get it off and regret it deeply. I've been using a hammer and punch to tighten and loosen the set up. Not sure what tools to use to get a tremendous enough grip to pull something like that off.

 

[Sidewinder Jerry]

I thought briefly. But i know i'll never get it off and regret it deeply. I've been using a hammer and punch to tighten and loosen the set up. Not sure what tools to use.

You can get it off with very high heat. What you need is an adjustable pin spanner tool.

 

[Wrench]

This is my latest attempt to get it to stop. I put small metal rod between the 3rd screw inlet and even used marine JB weld to possibly seize it all up. Cleared the threads of grease and soaked in blue lock tite and cured for 24 hours.

After 5 minutes of pedaling, the crank went from firm to ever so slightly wobbly. I am certain it will continuously unwind like it did before. If not, the wire will jam it up and leave me with some annoying amount of wobble.

The threads here are both "right-tight". Even the smaller "lock nut" i am sure that's not right, but it was the only way it would thread on.

Has the cup been tightened properly first

 

[Deliveryfoot]

Has the cup been tightened properly first

Not sure what the name of each part is. The part just underneath the "locknut" should be perfectly tight. If it isn't are you saying that the actual part connecting to the bicycle is slipping? Not sure how that would cause it to become wobbly.

 

[Wrench]

Not sure what the name of each part is. The part just underneath the "locknut" should be perfectly tight. If it isn't are you saying that the actual part connecting to the bicycle is slipping? Not sure how that would cause it to become wobbly.

The Bearing Cup screws into the frame BB
So if that is screwing itself into the frame farther everything else will become loose.
Does it become loose but the locknut is still tight?
But this might not be the problem

IMO you have not installed the crankset properly or you have a bearing going bad Maybe ya put the bearings in backwards
I suggest to take the crankset all apart and reassemble it.
Epoxy shouldn't have to be used I hope that epoxy comes off OK

 

[Chainlube]

The Bearing Cup screws into the frame BB
So if that is screwing itself into the frame farther everything else will become loose.
Does it become loose but the locknut is still tight?
But this might not be the problem

IMO you have not installed the crankset properly or you have a bearing going bad Maybe ya put the bearings in backwards
I suggest to take the crankset all apart and reassemble it.
Epoxy shouldn't have to be used I hope that epoxy comes off OK

Yup, done that myself. I knew as soon as I pedaled it a few strokes that something wasn't right. Take it apart and put it back together again.

 

[Deliveryfoot]

UPDATE:
Took apart the cup. Turns out the issue was crushed bearings cartridge on the drive side. I dont know the name, but its a light piece of metal that holds the bearings in a circle.

I'm only here to point this out before i forget to entirely. I'll try and let others know if its because i put the bearings in backwards or not. Or if its just because i tightened too much.