Not stoked.

[dudski]

well today i received my new wethepeople cranks in the mail. so this evening(actually 15 minutes ago) i set off to remove my cranks...i have with me my trusty syncros 8mm with the fatty yellow grip and my park x type bb tool... evolve cranks pop off easy as pie, left cup threads out no problemo and the grease is still fresh from when i put the cranks on 2 months ago. i move over to the drive side cup and for some odd reason it is really painful to turn out. when i put it in( put it in with my right hand after a playful dab of pedros on the threads then torqued accordingly) so after 20 minutes and a pulled back it looks like my beautiful flow frame is pooched. soo i have worked on one or two bikes in my time and have never seen such a thing...i am gonna try do the ol chase tomorrow at work but it seems to be fuuucked... now i'm kinda sad and dunno what to do.

any words of wisdoms from the wiser bicycle fixit people?

[Mountain Dewd]

your post confused me but ive cross threaded a bb before and the frame was fine after a running a chase. felt like a bone head though. i bet youll be okay dude.

good luck bro

[Straw]

Drive side BB threads are reverse threaded.

Maybe that's your problem?

Or have you already got the bb out?

[Kye]

If you crossed threaded it, it would have felt wrong when you put it in. It would be noticeable.

[stubz]

Drive side BB threads are reverse threaded.

Maybe that's your problem?

i beleive hes a mechanic so i think he knew that.


bad tap done when it was threaded??. that makes me sad. the purple was soo steezy!:(

[Kye]

i beleive hes a mechanic so i think he knew that.


bad tap done when it was threaded??. that makes me sad. the purple was soo steezy!:(


If he's a mechanic, I would hope he would know how to install a bb properly without screwing it up.

[corey@nsmb.com]

If he's a mechanic, I would hope he would know how to install a bb properly without screwing it up.

"when i put it in( put it in with my right hand after a playful dab of pedros on the threads then torqued accordingly)"

Sounds to me like he didn't do anything wrong here....If he threaded it in by hand there is no way he would have been able to cross thread it.

[dudski]

haha yeah thanks for the thread direction tip....
the cup is out it just took half an hour or so to get it out. and it left my driveside threads shredded and it wasn't cross threaded so i dunno wtf happened, it's like the end of the cup got damaged while it was in the frame and when it came out it pulled out the threads. annd yeas i have worked full time as the mechanic for a bike store for the last year and a half and have never seen such catastrophe in a new bike ahah.

[dudski]

took about 40 minutes to do the re tap. looks way better than it did but the new bb cup was a very tight fit.... i still have no idea what could have done that carnage though hah....new cranks are bling blangin... now if only they were the white ones.

[DrewM]

Thats crazy...

With BB's and pedals you should be able to thread the item in question 99% of the way in by hand and then just tighten it.

...

It reminds me of a guy I ran into in the Old Buck parking lot... he was on a sweet circa 1996 Giant 990 (yellow/red Tomac colours) and in the process of putting his Shimano DX clipless pedals on he had managed to put the right into the left and the left into the right :| ... so basically he could have clipped in if he had wanted to ride the bike backwards

Being younger (a year) and stupider (a bit) then I am now I used my pedal wrench to take them out for him (thinking back now I'm glad all the threads didn't come out as well...) and they actually threaded into the proper crank arms 90% of the way by hand and screwed in tight.

It made me wonder how much cursing and swearing must have been involved in getting those pedals into those cranks in the first place... they were a really nice set of 94 BCD XT cranks too... the thin silver forged ones... MMMmmmmmm....

[Straw]

I saw a set of LX 4 bolt cranks get ruined because of the same thing. cranks were LX before LX was that blue/grey colour and were silver. I'd say 1998. The threads were torn right out.

I think Mr Giant 990 was really lucky to not have ruined his pedals!

[biggles604]

One of the big problems I have with a lot of bike parts is that you have aluminium parts mating with aluminium, normally one part is anodised, but even with grease, when installing parts, especially BB cups which have a very fine thread pitch for their diameter, the pressures involved are incredible. High pressure means that the grease will be flowed away from pressure hotspots, and then the anodising will start to wear, once it has gone, you are left with aluminium on aluminium, which is bad since it's a galling metal. Once the metal starts to bind, nothing will remove it and it will strip out your threads as it is removed.
I had it happed on a friends brand new V10, the threads must have been cut with a dull tool because they weren't properly cut about 5mm into the BB shell, when I was inserting the BB, it galled about 6mm in and ripped out the outer threads. We were fortunate that we still had enough to work with after that though, and after recutting and chasing the threads it was all good.

Is there enough material to recut and chase the threads?

[dudski]

iiii did re cut them....and it seemed to do well it just took a looong time to clean them out to get the new bb cup to start but it did, and then was smooth sailing. sorta sounds like the same deal with the v10 but the shallow cut was near the end of the threads rather than just 5mm in.

[biggles604]

Glad to hear you salvaged it. In hindsight, having any threads in an aluminuim frame seems a bit silly, anything that needs to be screwed in should have nuts or inserts to prevent stripping.

[CraigH]

High pressure means that the grease will be flowed away from pressure hotspots, and then the anodising will start to wear, once it has gone, you are left with aluminium on aluminium, which is bad since it's a galling metal. Once the metal starts to bind, nothing will remove it and it will strip out your threads as it is removed.


I've run into the same thing with an aluminum frame when using a BB with aluminum cups. I think something better than standard bike grease is require, something along the lines of the anti-seize by titanium frame users when they use ti seatposts, ti bolts etc.

[biggles604]

I've run into the same thing with an aluminum frame when using a BB with aluminum cups. I think something better than standard bike grease is require, something along the lines of the anti-seize by titanium frame users when they use ti seatposts, ti bolts etc.

I used to have some grease called Never-Seez, it was a high pressure industrial graphite lube. It was brilliant, would stain your hands grey for weeks and worked better than anything else I have ever known, I'll probably get cancer from using it too :P. Galling metals shouldn't come into contact with each other, ie: Ti, Stainless steel and aluminium. Titanium is the weird one, since it bonds to itself. Remember, stainless into Al is a bad idea without grease!