Are My Cranks Toast?

[Kenny Lee]

Recently I've noticed a creaking noise coming from my BB area. Upon inspection I found that my crank
arms (L & R) came loose by themselves. I wrenched them down real good and went out for a 30k ride.
When I got home the crank bolts were once again coming loose. FWIW, I changed my BB to a Phil Wood
one two weeks ago and am using Record cranks. I've been using these cranks for 15,000k. These cranks
were ridden with lateral play of about 0.2mm for about the first 14,500k (lousy BB install by LBS).
After which the lateral play grew to 2.0mm with grinding sound coming from the BB. That's when I
replaced the BB. If my cranks are toast, was it because I rode it too long in its original wobbly
state? Or is it something else I did?

Still on the bike fixer learning curve, Kenny Lee

 

[Alex Rodriguez]

In article <[email protected]>, [email protected] says...

>Recently I've noticed a creaking noise coming from my BB area. Upon inspection I found that my
>crank arms (L & R) came loose by themselves.

It is strange that you would hear a creak from loose arms, but not feel loose arms. When your arms
are loose, you should feel it.

>I wrenched them down real good and went out for a 30k ride. When I got home the crank bolts were
>once again coming loose.

Are the cranks loose or just the bolts? Also, when you say loose, do you mean finger tight or just
less tight than when you initially tightened them.

> FWIW, I changed my BB to a Phil Wood one two weeks ago and am using Record cranks. I've been using
> these cranks for 15,000k. These cranks were ridden with lateral play of about 0.2mm for about the
> first 14,500k (lousy BB install by LBS). After which the lateral play grew to 2.0mm with grinding
> sound coming from the BB. That's when I replaced the BB. If my cranks are toast, was it because I
> rode it too long in its original wobbly state? Or is it something else I did?

If your BB was loose, then your cranks should be fine, but your BB is toast.
-------------
Alex

 

[Tbgibb]

In article <[email protected]>, Kenny Lee <[email protected]> writes:

>Recently I've noticed a creaking noise coming from my BB area. Upon inspection I found that my
>crank arms (L & R) came loose by themselves. I wrenched them down real good and went out for a 30k
>ride. When I got home the crank bolts were once again coming loose. FWIW, I changed my BB to a Phil
>Wood one two weeks ago and am using Record cranks. I've been using these cranks for 15,000k. These
>cranks were ridden with lateral play of about 0.2mm for about the first 14,500k (lousy BB install
>by LBS). After which the lateral play grew to 2.0mm with grinding sound coming from the BB. That's
>when I replaced the BB. If my cranks are toast, was it because I rode it too long in its original
>wobbly state? Or is it something else I did?

My best guess is that when the Phil BB went in the cranks were not tightened enough. I don't think
the 0.2 mm (?about? how did you measure that?) play was a factor in that. It also sounds like the 2
mm play was caused by the bad BB (because of the grinding sound) and not by loose cranks.

Your cranks are almost certainly toast.

The figure I see most often, and use myself, for making those crank bolts properly tight is 35 ft
lbs. I have to have an 18 inch torque wrench to get them that tight.

And . . . you should grease your tapers. The cranks will seat fully that way. And, once you have put
the torque to the crank bolts DO NOT re-tighten them, you'll risk splitting the cranks.

The taper greasing part will probably be challenged and possible flamed.

Tom Gibb <[email protected]

 

[Kenny Lee]

Kenny Lee wrote:
> Recently I've noticed a creaking noise coming from my BB area. Upon inspection I found that my
> crank arms (L & R) came loose by themselves. I wrenched them down real good and went out for a 30k
> ride. When I got home the crank bolts were once again coming loose. FWIW, I changed my BB to a
> Phil Wood one two weeks ago and am using Record cranks. I've been using these cranks for 15,000k.
> These cranks were ridden with lateral play of about 0.2mm for about the first 14,500k (lousy BB
> install by LBS). After which the lateral play grew to 2.0mm with grinding sound coming from the
> BB. That's when I replaced the BB. If my cranks are toast, was it because I rode it too long in
> its original wobbly state? Or is it something else I did?
>
> Still on the bike fixer learning curve, Kenny Lee
>

Sorry folks,

I should have said the crank bolts were coming loose not the crank arms. Possibly I'm not torqing
them down enough?

Kenny Lee

 

[Qui Si Parla Ca]

kent-<< If my cranks are toast, was it because I rode it too long in its original wobbly state? Or
is it something else I did?

Loose cranks will kill cranks=pretty simple. If they were loose initially because the LBS installed
them poorly-they need to pony up-

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"

 

[Jobst Brandt]

Kenny Lee writes:

> Recently I've noticed a creaking noise coming from my BB area. Upon inspection I found that my
> crank arms (L & R) came loose by themselves. I wrenched them down real good and went out for a 30k
> ride. When I got home the crank bolts were once again coming loose. FWIW, I changed my BB to a
> Phil Wood one two weeks ago and am using Record cranks. I've been using these cranks for 15,000k.

If the cranks were ridden with loose bolts, and then became loose again shortly after tightening,
they are irreparably damaged.

http://draco.acs.uci.edu/rbfaq/FAQ/8f.11.html

> These cranks were ridden with lateral play of about 0.2mm for about the first 14,500k (lousy BB
> install by LBS). After which the lateral play grew to 2.0mm with grinding sound coming from the
> BB. That's when I replaced the BB. If my cranks are toast, was it because I rode it too long in
> its original wobbly state? Or is it something else I did?

Your description is confusing. Looseness in BB bearings does not affect cranks or their press fit on
the spindle. It cannot damage cranks. Where and how did you determine that there was 0.2mm play?
Does this mean that the pedal end of the crank could be rattled sideways that much, or what? Such
small play can normally be felt only as a light "clunk" when pushing laterally on the end of the
crank by hand.

Jobst Brandt [email protected] Palo Alto CA

 

[Kenny Lee]

Alex Rodriguez wrote:
> In article <[email protected]>, [email protected] says...
>
>
>>Recently I've noticed a creaking noise coming from my BB area. Upon inspection I found that my
>>crank arms (L & R) came loose by themselves.
>
>
> It is strange that you would hear a creak from loose arms, but not feel loose arms. When your arms
> are loose, you should feel it.
>
>
>>I wrenched them down real good and went out for a 30k ride. When I got home the crank bolts were
>>once again coming loose.
>
>
> Are the cranks loose or just the bolts? Also, when you say loose, do you mean finger tight or just
> less tight than when you initially tightened them.
The bolts are coming loose. Before going out on a ride the bolts are tight as can be. Upon return
they've gotten loose. How loose? Loose enough to have to tighten them down again.

Kenny Lee

 

[Appkiller]

Seems to me there is something wrong in the statement:

"And, once you have put the torque to the crank bolts DO NOT re-tighten them, you'll risk splitting
the cranks."

If indeed the crank bolts loosen, what is the owner supposed to do? Damned if they do (YOU'LL SPLIT
YER CRANK!), damned if they don't (YOU'LL ROUND YER SOCKET!).

This seems to be the missing piece in all of the thousands of posts warning about the re-tightening
of crank bolts. If, after applying the proper torque to the crank bolts, they become loose, what is
one supposed to do?

Not that I am a fan of the vicious cycle of dangerous and evil (!) repeated crank bolt tightening
but if the crank bolt is loose, the solution seems obvious. Perhaps the real answer is that if the
crank bolts are properly torqued in the first place, they won't come loose. And if they do to the
extent that there is creaking or play in the arms, the owner is due a warranty replacement because
the taper socket or bb spindle was machined improperly in the first place.

Or maybe there is another answer (remove, re-install and re-torque rather than just
tightening?). Anyone?

App

[email protected] (TBGibb) wrote in message news:<[email protected]>...
> In article <[email protected]>, Kenny Lee <[email protected]> writes:
>
> >Recently I've noticed a creaking noise coming from my BB area. Upon inspection I found that my
> >crank arms (L & R) came loose by themselves. I wrenched them down real good and went out for a
> >30k ride. When I got home the crank bolts were once again coming loose. FWIW, I changed my BB to
> >a Phil Wood one two weeks ago and am using Record cranks. I've been using these cranks for
> >15,000k. These cranks were ridden with lateral play of about 0.2mm for about the first 14,500k
> >(lousy BB install by LBS). After which the lateral play grew to 2.0mm with grinding sound coming
> >from the BB. That's when I replaced the BB. If my cranks are toast, was it because I rode it too
> >long in its original wobbly state? Or is it something else I did?
>
> My best guess is that when the Phil BB went in the cranks were not tightened enough. I don't think
> the 0.2 mm (?about? how did you measure that?) play was a factor in that. It also sounds like the
> 2 mm play was caused by the bad BB (because of the grinding sound) and not by loose cranks.
>
> Your cranks are almost certainly toast.
>
> The figure I see most often, and use myself, for making those crank bolts properly tight is 35 ft
> lbs. I have to have an 18 inch torque wrench to get them that tight.
>
> And . . . you should grease your tapers. The cranks will seat fully that way. And, once you have
> put the torque to the crank bolts DO NOT re-tighten them, you'll risk splitting the cranks.
>
> The taper greasing part will probably be challenged and possible flamed.
>
> Tom Gibb <[email protected]

 

[Robin Hubert]

"Kenny Lee" <[email protected]> wrote in message news:[email protected]...
> Kenny Lee wrote:
> > Recently I've noticed a creaking noise coming from my BB area. Upon inspection I found that my
> > crank arms (L & R) came loose by themselves. I wrenched them down real good and went out for a
> > 30k ride. When I got home the crank bolts were once again coming loose. FWIW, I changed my BB to
> > a Phil Wood one two weeks ago and am using Record cranks. I've been using these cranks for
> > 15,000k. These cranks were ridden with lateral play of about 0.2mm for about the first 14,500k
> > (lousy BB install by LBS). After which the lateral play grew to 2.0mm with grinding sound coming
> > from the BB. That's when I replaced the BB. If my cranks are toast, was it because I rode it too
> > long in its original wobbly state? Or is it something else I did?
> >
> > Still on the bike fixer learning curve, Kenny Lee
> >
>
> Sorry folks,
>
> I should have said the crank bolts were coming loose not the crank arms. Possibly I'm not torqing
> them down enough?
>

It's time for a FAQ moment ... sorry, I don't have the location. See Google.

Robin Hubert

 

[Kenny Lee]

[email protected] wrote:
> Kenny Lee writes:
>
>
>>Recently I've noticed a creaking noise coming from my BB area. Upon inspection I found that my
>>crank arms (L & R) came loose by themselves. I wrenched them down real good and went out for a 30k
>>ride. When I got home the crank bolts were once again coming loose. FWIW, I changed my BB to a
>>Phil Wood one two weeks ago and am using Record cranks. I've been using these cranks for 15,000k.
>
>
> If the cranks were ridden with loose bolts, and then became loose again shortly after tightening,
> they are irreparably damaged.
>
> http://draco.acs.uci.edu/rbfaq/FAQ/8f.11.html
>
>
>>These cranks were ridden with lateral play of about 0.2mm for about the first 14,500k (lousy BB
>>install by LBS). After which the lateral play grew to 2.0mm with grinding sound coming from the
>>BB. That's when I replaced the BB. If my cranks are toast, was it because I rode it too long in
>>its original wobbly state? Or is it something else I did?
>
>
> Your description is confusing. Looseness in BB bearings does not affect cranks or their press fit
> on the spindle. It cannot damage cranks. Where and how did you determine that there was 0.2mm
> play? Does this mean that the pedal end of the crank could be rattled sideways that much, or what?
> Such small play can normally be felt only as a light "clunk" when pushing laterally on the end of
> the crank by hand.
>
> Jobst Brandt [email protected] Palo Alto CA
The person who installed the first BB did not chase the BB shell as it was a new frame. One of the
BB cups was not screwed in all the way allowing the spindle to have some lateral play. As of now I
think that my best case scenerio is that I need to use a torque wrench and torque it down to specs.
I've never ridden with loose cranks before but this is the first time I've seen crank bolts loosen
after a ride.

Kenny Lee

 

[David L. Johnso]

On Thu, 16 Jan 2003 22:32:54 -0500, Kenny Lee wrote:

>> Are the cranks loose or just the bolts? Also, when you say loose, do you mean finger tight or
>> just less tight than when you initially tightened them.
> The bolts are coming loose. Before going out on a ride the bolts are tight as can be. Upon return
> they've gotten loose. How loose? Loose enough to have to tighten them down again.

Read the FAQ on this.

1) If the cranks had significant play -- enough to feel -- for more than a few miles then they
probably are toast. The square taper hole will be deformed by the lashing back and forth, and
will never really be right again.

2) You do NOT want to keep tightening the bolts. Read the FAQ. The cranks will continue to squirm
up and down the taper of the bottom bracket. If you re-tighten the bolt, they will squirm
further up, deforming the hole as in 1). If you continue, you will eventually crack the crank.

--

David L. Johnson

__o | "Business!" cried the Ghost. "Mankind was my business. The _`\(,_ | common welfare was my
business; charity, mercy, forbearance, (_)/ (_) | and benevolence, were, all, my business. The
dealings of my trade were but a drop of water in the comprehensive ocean of my business!"
--Dickens, "A Christmas Carol"

 

[Harris]

"Kenny Lee" wrote:
> The person who installed the first BB did not chase the BB shell as it was a new frame.

That's when it should be chased (if the manufacturer didn't do it).

> As of now I think that my best case scenerio is that I need to use a torque wrench and torque it
> down to specs. I've never ridden with loose cranks before but this is the first time I've seen
> crank bolts loosen after a ride.

If it was properly torqued to begin with, then re-tightening "to spec" may not be a good idea as it
may force the cranks too far up the taper. How loose are the bolts anyway?

The fact that the bolts aren't as tight as they were originally doesn't necessarily mean that they
backed out. It probably means the crank worked its way further up the taper.

BTW, to prevent the bolts from backing out (and possibly loosing them), it's a good idea to install
the "dust caps" properly.

Art Harris

 

[Robin Hubert]

"David L. Johnson >" <David L. Johnson <[email protected]> wrote in message
news:[email protected]...
> On Thu, 16 Jan 2003 22:32:54 -0500, Kenny Lee wrote:
>
> >> Are the cranks loose or just the bolts? Also, when you say loose, do you mean finger tight or
> >> just less tight than when you initially tightened them.
> > The bolts are coming loose. Before going out on a ride the bolts are tight as can be. Upon
> > return they've gotten loose. How loose? Loose enough to have to tighten them down again.
>
> Read the FAQ on this.
>
> 1) If the cranks had significant play -- enough to feel -- for more than a few miles then they
> probably are toast. The square taper hole will be deformed by the lashing back and forth, and
> will never really be right again.
>
> 2) You do NOT want to keep tightening the bolts. Read the FAQ. The cranks will continue to squirm
> up and down the taper of the bottom bracket.

No, just up, as I understand it. That is, until they reach equilibrium.

>If you re-tighten the bolt, they will squirm further up, deforming the hole as in 1). If you
>continue, you will eventually crack the crank.
>
> --
>
> David L. Johnson
>
> __o | "Business!" cried the Ghost. "Mankind was my business. The _`\(,_ | common welfare was my
> business; charity, mercy, forbearance, (_)/ (_) | and benevolence, were, all, my business. The
> dealings of my trade were but a drop of water in the comprehensive ocean of my business!"
> --Dickens, "A Christmas Carol"

 

[Jon Isaacs]

>Sorry folks,
>
>I should have said the crank bolts were coming loose not the crank arms. Possibly I'm not torqing
>them down enough?
>
>Kenny Lee

Are the bolts actually coming loose, ie so you can move them with your fingers, or are they just
looser than they were but still reasonably tight?

A torque wrench is the right tool here if you are uncertain.

Also, were the cranks tight on the shaft when you removed them from the previous BB?

Jon Isaacs

Jon Isaacs

 

[Qui Si Parla Ca]

Tom-<< And . . . you should grease your tapers. The cranks will seat fully that way.

Yikes, when will we learn to just not include these tidbits??

'Lube' will not 'allow' any crank to 'fully seat'..

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"

 

[Kenny Lee]

Jon Isaacs wrote:

> Are the bolts actually coming loose, ie so you can move them with your fingers, or are they just
> looser than they were but still reasonably tight?
I never gave them the finger test but they were loose enough to warrent tightening.
>
> A torque wrench is the right tool here if you are uncertain.
Buying the Park Tool TW-2 this tuesday.
>
> Also, were the cranks tight on the shaft when you removed them from the previous BB?
Yes, they were. Kenny Lee

 

[Robin Hubert]

"Jon Isaacs" <[email protected]> wrote in message
news:[email protected]...
> >Seems to me there is something wrong in the statement:
> >
> >"And, once you have put the torque to the crank bolts DO NOT re-tighten them, you'll risk
> >splitting the cranks."
>
> >If indeed the crank bolts loosen, what is the owner supposed to do? Damned if they do (YOU'LL
> >SPLIT YER CRANK!), damned if they don't (YOU'LL ROUND YER SOCKET!).
>
> >This seems to be the missing piece in all of the thousands of posts warning about the
> >re-tightening of crank bolts. If, after applying the proper torque to the crank bolts, they
> >become loose, what is one supposed to do?
>
> The crank bolts will loosen somewhat as the crank squirms on the axle. If properly installed, they
> will not come loose, they will just be somewhat
looser
> than the original torque setting.

To clarify (um, please pardon me, Jon), the bolts don't loosen, but the crank moves away from them
(effectively loosening them).

>
> A Jobst points out in the FAQ, continuing to retightening them eventually
will
> cause them to split.
>
> Do the job right the first time and then leave them alone.
>
> Jon Isaacs
>

Robin Hubert

 

[John Everett]

On Fri, 17 Jan 2003 22:04:01 +0800, Kenny Lee <[email protected]> wrote:

>Jon Isaacs wrote:
>
>> Are the bolts actually coming loose, ie so you can move them with your fingers, or are they just
>> looser than they were but still reasonably tight?
>I never gave them the finger test but they were loose enough to warrent tightening.
>>
>> A torque wrench is the right tool here if you are uncertain.
>Buying the Park Tool TW-2 this tuesday.

Don't know what these cost, but at $29.95(US) the Craftsman beam type (looks pretty much like the
one I've been using for about 35 years or so) is a lot cheaper than a new set of cranks. See:

http://www.sears.com/sr/product/summary/productsummary.jsp?BV_SessionID=@@@@1339577024.1042917414@@-
@@&BV_EngineID=ccigadchfkmgkddcehgcemgdffmdfko.0&vertical=TOOL&bidsite=&pid=00944978000

jeverett3<AT>earthlink<DOT>net http://home.earthlink.net/~jeverett3

 

[Tbgibb]

In article <[email protected]>, [email protected] (Qui si parla
Campagnolo) writes:

>Tom-<< And . . . you should grease your tapers. The cranks will seat fully that way.
>
>Yikes, when will we learn to just not include these tidbits??
>
>'Lube' will not 'allow' any crank to 'fully seat'..

I didn't say "allow" I said "WILL" Anyway, the devil made me say that ;-)

I do grease my tapers, and I do make them very tight, and I never re-tighten them, and they NEVER
come loose and I've never split one.

Tom Gibb <[email protected]

 

[Qui Si Parla Ca]

tom-<< I do grease my tapers, and I do make them very tight, and I never re-tighten them, and they
NEVER come loose and I've never split one.

Peter-<< I do not grease my tapers, and I do make them very tight, and I never re-tighten them, and
they NEVER come loose and I've never split one.

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"