# Greasing BB square taper & crank bolt a big NO-NO !



## bolo yeung (Jul 14, 2008)

I've made quite an expensive mistake by the looks of it.

Recently built up an old rig and installed a new 2006 Record 10 speed chainset plus new Chorus bb (square taper). For life of me don't know what I was thinking... I greased not only the taper but also the hole where the crank bolt sits! (what a twit I hear you say?!)

Of course during the first ride the left crank arm came loose. I tightened it up and carried on riding. But yet again around 3-4 miles later the left crank had come loose again.

My guess is that the crank may well be ruined as I carried on riding (including some fairly steep climbs) and re-tightening until I got back home.

WHAT I NEED TO KNOW THOUGH IS: if I some how get a little degreaser inside the threaded hole on each end of the BB is possible to save the BB.

Only now have I invested in a couple or torque wrenches as guessing campy's crank bolt recommendation of 32-38NM without one just isn't possible!! I"VE LEARNT MY LESSON THE HARD WAY....


.........DOH!


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## Spunout (Aug 12, 2002)

You have not tighened it up in enough in the first place. 

Degrease the taper, it doesn't need any grease. The crank bolt won't make a difference.


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## Guest (Sep 1, 2009)

If you *don't* grease the crank fixing bolt you will never get it off the bike again.

Just saying.


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## Touch0Gray (May 29, 2003)

Campy's instructions say not to grease, the bolts I wouldn't think was an issue but the tapered spindle, I had greased before I read that. I took it apart and de-greased. The bolts come with blue stuff on them.
You should use a torque wrench though.

If the bolt isn't torqued properly you had a second problem as well, the cranks was not seated on the taper far enough and the chain-line was off as well


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## bolo yeung (Jul 14, 2008)

Is there anyway of telling if the crank is toast ? (It was the left crank arm in this case that kept coming off)

During a ride if worked it's way loose several times, the first of which I must carried on riding with for 3 or so miles before I realised. At first I thought my cleat had come loose.


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## superflychief (Mar 25, 2008)

the problem with square taper is that the more you take it on and off and the harder you tighten it the more you wear the crank arm. The BB is a much stronger metal then the arm so the crank arm hole loostens up over time and you have to tighten it harder and harder. Sorry but you might have toasted your crank. Either way, completely degrease the BB spindle and dont forget to clean out the crank arm hole as well. Remount and give it a good tighten. You would have to tighten it like crazy by hand before you did any damage to the BB spindle threads so go ahead and torque it down. You might not have completely ruined it but I think you may have shortened it's life span.


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## Indyfan (Mar 30, 2004)

It will look rounded on the side that faces the frame. If you aren't sure, take it to your LBS and have them take a look at it.

In the future, grease the threads on the fixing bolt, but not the taper. Obviously degrease the surfaces on the crank and BB spindle, then use a torque wrench and tighten both sides to the torque spec in the paperwork that came with the parts. If you don't have the paperwork, Campy's website should display it in the tech section. Probably a PDF of the assembly paperwork. After all that ride it and check the bolts on both sides after each ride with a normal allen wrench. Just turn the allen wrench as if you were loosening the bolt (without actually loosening it) to see if there's a proper amount of resistance. If you don't think they're tight enough, loosen both sides a little and re-tighten with the torque wrench. If all seems good for 3-4 rides, check them after every 3rd ride for a few rides. Again, if all seems good, you're probably safe. Why so anal about it and checking so much? Because that's an expensive (and soon to be hard to get) part and there's a known problem with it.

Good luck,

Bob


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## JCavilia (Sep 12, 2005)

Your problem was not the grease. The debate about whether or not to grease square tapers has been raging for decades, inconclusively. There is no downside to greasing the bolt threads. Your problem was failing to torque it enough in the first place. It takes a lot. 38 Newton-meters works out to something over 50 pounds of force at the end of 6-inch allen wrench. You didn't tighten enough the first time, and when you re-tightened on the road you were too cautious again.

It probably suffered some damage, but it might be fine. If you've now got a torque wrench, torque it to the high end of the specs, and you might be okay for a long time. 

Personally, I lightly grease the tapers, and I put blue loctite on the threads. The loctite acts like a lube when it's wet. As long as I torque properly I've never had a problem either with the crank loosening or with removing the bolts when I need to.


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## livin4lax09 (Mar 15, 2008)

yeah, a lot of torque does it. I had the same issue with one of my cranks, but after i torqued it down really hard, no more problems.


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## Mel Erickson (Feb 3, 2004)

I doubt you've ruined your crank or spindle. Possible but not likely after one ride and you stopping to tighten when you noticed it becoming loose. When assembling cranks I follow the manufacturers directions and Campy says no grease on the spindle, so no grease it is. De-grease and reassemble using the proper torque as others have said. You can tighten the bolt enough without a torque wrench but how would you know when proper torque was achieved? Yes, a torque wrench is necessary for this job but not because another wrench won't tighten it enough.

As for greasing the bolt, yes, this is advisable.


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## MR_GRUMPY (Aug 21, 2002)

Back in the day, I'd grease my tapers, and use a Campy peanut butter wrench to install the fixing bolt. No torque wrench, but I'd use my full force to tighten the bolt with that short wrench.


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## bigbill (Feb 15, 2005)

I grease the fixing bolt. Not a lot, just to coat the threads. My only square taper bike is my commuter with a PW stainless bb and a 7410 DA crankset. It has a 8mm allen head bolt and I use socket allen and ratchet to install it. I apply "star" torque (use enough force to see stars) with a ten inch ratchet handle. I don't grease the spindle but I don't see how it would make a difference either way if you didn't use enough torque in the first place.


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## jmlapoint (Sep 4, 2008)

My FG is a 1978 Steel Track Frame with original Campy Pista BB and Pista Cranks.
Like Mr_Grumpy, I have always greased the Tapered Spindle and the Crank Bolts. I always thought greasing provided a tight fit and eliminated any creaking. I also use the Campy 'peanut-butter' Wrench to tighten the Crank Bolts.


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## mtbbmet (Apr 2, 2005)

I always grease the spindle and bolts. Just something I've always done. Is it needed, maybe not. Will it hurt anything? Definately not.


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## martinrjensen (Sep 23, 2007)

*torque and grease*

The actual torque may not change depending on whether or not there is grease on the surface, but the pressure on the parts sure will. I know that with most industrial parts tapers are never supposed to be greased as you are libel to crack the outer part. And the torque values are assuming the surface is clean and dry. It wouldn't surprise me to see that this square taper is assuming a clean dry surface for the torque figure also.


JCavilia said:


> Your problem was not the grease. The debate about whether or not to grease square tapers has been raging for decades, inconclusively. There is no downside to greasing the bolt threads. Your problem was failing to torque it enough in the first place. It takes a lot. 38 Newton-meters works out to something over 50 pounds of force at the end of 6-inch allen wrench. You didn't tighten enough the first time, and when you re-tightened on the road you were too cautious again.
> 
> It probably suffered some damage, but it might be fine. If you've now got a torque wrench, torque it to the high end of the specs, and you might be okay for a long time.
> 
> Personally, I lightly grease the tapers, and I put blue loctite on the threads. The loctite acts like a lube when it's wet. As long as I torque properly I've never had a problem either with the crank loosening or with removing the bolts when I need to.


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## Guest (Sep 1, 2009)

I grease the bolt and the spindle.

Always have.

Never ruined a crank.

Never had one stick either.

Don't care what the instructions say.


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## wim (Feb 28, 2005)

*Lots of grease.*

Many years of greasing the taper, the spindle hole, the bolt threads and the underside of the bolt head—never a problem. Did it all *need *greasing? I don't know.


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## MR_GRUMPY (Aug 21, 2002)

If you remove and install a set of cranks every week (why would you do this?) greasing the spindle could lead to the cranks being forced onto the spindle farther and farther each time, until it bottoms out on the non-tapered part of the spindle. Under normal circumstances, this should never happen.


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## jsellers (Feb 14, 2008)

Grease taper and threads. The grease is because it is two different metal types so they don't fuse together.


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## MR_GRUMPY (Aug 21, 2002)

That never happens between spindle and arm.....All my brank bolts were steel..
I would grease them in order to get rid of the natural friction...(a little like putting a drop of oil on spoke threads, when building wheels)


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## Mike T. (Feb 3, 2004)

toomanybikes said:


> I grease the bolt and the spindle.
> Always have.
> Never ruined a crank.
> Never had one stick either.
> Don't care what the instructions say.


Me too - and for 5 decades. Never a problem.


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## Metaluna (Aug 26, 2005)

My inclination is to grease both the taper and bolt. I've also installed Campy cranks dry (as per instructions) with no problems, however I tend to remove my cranks about once a year on average for various reasons (maintenance, gearing changes, general tinkering) so seizing is not an issue for me.

Interesting side note: I was reading some FAQs over at the Phil Wood website (I'm currently running a Phil BB on one of my Campy bikes) and they recommend grease on their spindles, even for Campy crankarms. They claim their tapers were designed with grease in mind, though they're not really adamant about it. I believe they make their tapers slightly concave, though I'm not sure what benefits this has.


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## paredown (Oct 18, 2006)

Token (like Campy) recommends the square taper actually be degreased before assembly... 

That said, I've done it both ways. I've also generally used fresh Loctite blue on the bolts before torquing.

Your crank is probably fine, BTW.


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