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ultegra octalink: tick Tick TICK TICK TICK!



 
 
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  #1  
Old January 28th 05, 12:44 AM
H. Guy
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Default ultegra octalink: tick Tick TICK TICK TICK!

when i built up my last bike, i needed a triple. stop
snickering. i just needed a triple, that's all. and
campy had two alternatives: ugly and expensive, so i went
with shimano for the first time in around a decade and a
half. at first, all was wonderful, but within six months
(let's say 3,000 miles or so) the right crankarm started
ticking against the octalink spindle. so i did the kind of
things i normally would do: pull it off, clean it, rotate
it 90 (or in this case) 45 degrees, etc. and i still came
out with TICK TICK TICK everytime my pedals came round.

and NO, it isn't the pedals, and it isn't the cleat.

finally, i'd just had it and (1) schmeered a little grease
on the spindle, despite years of experience screaming in my
head to NOT DO THAT. i also (2) bought a record triple 9
at a super bargain price once everybody decided that 9 speed
was so last week.

now, before i put the record on i thought i'd check and see
if this is a common complaint with ultegra octalink, and if
it's at all curable without resorting to method (1) above every
couple of months.
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  #2  
Old January 28th 05, 03:30 AM
hhu
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It isn't the bearings, is it?
  #3  
Old January 28th 05, 03:59 AM
dianne_1234
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On Thu, 27 Jan 2005 23:44:09 GMT, "H. Guy"
wrote:

at first, all was wonderful, but within six months
(let's say 3,000 miles or so) the right crankarm started
ticking against the octalink spindle.


finally, i'd just had it and (1) schmeered a little grease
on the spindle, despite years of experience screaming in my
head to NOT DO THAT.


The Octalink service instructions recommend grease.
http://www.shimano-europe.com/cyclin..._pdf/16T0B.pdf
  #4  
Old January 28th 05, 04:10 AM
Meccanico di Bici
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Very common. Grease the livin' bejesus out of those splines! Octolink
is an interference fit, not a press fit. The splines on the crank and
the spindle bottom out onto eachother. Lots-o-grease will keep it
quiet. NEVER grease the tapers on a square spindle, but grease splines
to your hearts content.
--Jim

  #5  
Old January 28th 05, 05:31 AM
Tim McNamara
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"Meccanico di Bici" writes:

Very common. Grease the livin' bejesus out of those splines!
Octolink is an interference fit, not a press fit. The splines on the
crank and the spindle bottom out onto eachother. Lots-o-grease will
keep it quiet. NEVER grease the tapers on a square spindle, but
grease splines to your hearts content.


I've been greasing the tapers of cranks for 25 years, never had a
problem as a result. In order for the retaining bolt to be properly
torqued, the taper, the bolt threads and the washer should be greased.
Friction will cause a false reading.
  #6  
Old January 28th 05, 06:01 AM
Werehatrack
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On 27 Jan 2005 19:10:20 -0800, "Meccanico di Bici"
may have said:

Very common. Grease the livin' bejesus out of those splines! Octolink
is an interference fit, not a press fit. The splines on the crank and
the spindle bottom out onto eachother. Lots-o-grease will keep it
quiet. NEVER grease the tapers on a square spindle, but grease splines
to your hearts content.


Some crank and BB installation instructions I've had specifically
recommended greasing the surfaces. YMMV; I don't think it makes a
difference *provided* that the retaining bolt is torqued adequately,
and IMLE this is not always the same as "torqued to the manufacturer's
specifications."

--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.
  #7  
Old January 28th 05, 03:02 PM
Qui si parla Campagnolo
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H guy- when i built up my last bike, i needed a triple. stop
snickering. i just needed a triple, that's all. and
campy had two alternatives: ugly and expensive, BRBR

Hmmm, Centaur looks like Record and is less expensive than Ultegra.

finally, i'd just had it and (1) schmeered a little grease
on the spindle, despite years of experience screaming in my
head to NOT DO THAT. BRBR


maybe read the literature that comes with the crank. MUST grease the octalink
spindle threads. NOT the Campagnolo suqare taper spindle.

Grease it, align the splines w/o the little cap on and tighten it until IT
STOPS with a big 8mm allen wrench.

Peter Chisholm
Vecchio's Bicicletteria
1833 Pearl St.
Boulder, CO, 80302
(303)440-3535
http://www.vecchios.com
"Ruote convenzionali costruite eccezionalmente bene"
  #8  
Old January 28th 05, 03:03 PM
Qui si parla Campagnolo
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Tim writes- I've been greasing the tapers of cranks for 25 years, never had a
problem as a result. In order for the retaining bolt to be properly
torqued, the taper, the bolt threads and the washer should be greased.
Friction will cause a false reading. BRBR

I write- I've never greased the tapers of cranks for 25 years, never had a
problem as a result. In order for the retaining bolt to be properly
torqued, the bolt threads and the washer should be greased, but not the taper.
Friction will cause a false reading. BRBR


Peter Chisholm
Vecchio's Bicicletteria
1833 Pearl St.
Boulder, CO, 80302
(303)440-3535
http://www.vecchios.com
"Ruote convenzionali costruite eccezionalmente bene"
  #9  
Old January 28th 05, 04:08 PM
Tim McNamara
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(Qui si parla Campagnolo ) writes:

Tim writes-


I've been greasing the tapers of cranks for 25 years, never had a
problem as a result. In order for the retaining bolt to be
properly torqued, the taper, the bolt threads and the washer should
be greased. Friction will cause a false reading.

I've never greased the tapers of cranks for 25 years, never had a
problem as a result. In order for the retaining bolt to be properly
torqued, the bolt threads and the washer should be greased, but not
the taper.Friction will cause a false reading.


Yes, and you're likely getting false readings with your torque wrench
because of the friction between the male and female tapers.

Bicycle mechanics "in the know" tend to be the only people in all of
the mechanical world who advocate not greasing such interfaces. As
far as I can tell, the belief is that greasing the tapers will either
(a) cause the crank to fall off or (b) cause the crank to split.
Neither is actually true.

From the FAQ:

Subject: 8f.11 Installing Cranks From: Jobst Brandt


The admonition to not lubricate the tapers of the crank spindle seems
to find life only on bicycle cranks, of all the machines I have seen.
I have pursued the "dry assembly" instruction by talking to crank
manufacturers and discovered that they apparently had warranty claims
from customers who split their cranks open. It is easy to prove that
cranks cannot split by over-tightening simply by attempting to do so.
It is not possible to split a major brand crank this way, the bolt
will fail first.

Crank failure from "over-tightening" is caused by the re-tightening of
previously properly installed cranks. Once installed, a crank always
squirms on its taper, and because the retaining bolt prevents it from
coming off, it elbows itself away from the bolt and up the taper ever
so slightly. This can be detected by the looseness of the retaining
bolt after the bicycle has been ridden hard.

Grease in this interface does not affect performance, because only the
press fit, not friction, transmits load from crank to spindle. As any
bicycle mechanic can tell you, crank bolts are often appreciably
looser after use, the left one more so than the right. This occurs
because the left crank transmits torque and bending simultaneously
while the right crank transmits these forces one at a time. The right
crank puts no significant torque into the spindle. Either way, the
looseness occurs because loads make the crank squirm on the spindle
and the only direction it can move is up the taper, the retaining bolt
blocking motion in the other direction.

Regardless, whether grease or no grease is used, in use the spindle
and crank will make metal to metal contact and cause fretting
corrosion for all but the lightest riders. The purpose of the
lubricant is to give a predictable press fit for a known torque. If
the spindle is completely dry this cannot be said, and even with
marginal lubrication, some galling may occur on installation.
Lubrication is only used to guarantee a proper press because the
lubricant is displaced from the interface in use. Taper faces of
spindles show erosion and rouge after substantial use, evidence that
the lubricant was displaced.

"Dust caps" aren't just dust caps but retention for loose bolts. It is
not that the bolt unscrews but that the crank moves up the taper.
However, once the screw is unloaded it can subsequently unscrew and
fall out if there is no cap.

Because cranks squirm farther up the taper when stressed highly, the
unwitting mechanic believes the screw got loose, rather than that the
crank got tighter. By pursuing the crank with its every move up the
spindle, ultimately the crank will split. It is this splitting that
has been incorrectly diagnosed as being caused by lubrication. I have
never seen a warning against re-tightening cranks after having been
installed with a proper press fit. It is here where the warning
belongs, not with lubrication.

For the press fit to work properly, the pressure must be great enough
to prevent elastic separation between the crank and spindle under
torque, bending, and shear loads. This means that no gap between crank
and spindle should open when pedaling forcefully. Friction has no
effect on the transmission of torque because the crank creeps into a
position of equilibrium on the spindle in a few hard strokes.

Failure of this interface occurs when the press fit is too loose
allowing a gap open between spindle and crank. Torque is transmitted
by the entire face of the press fit, both the leading edge whose
contact pressure increases and the trailing edge whose contact
pressure decreases. If lift-off occurs, the entire force bears only on
the leading edge and plastic failure ensues (loose crank syndrome).
Tightening the retaining screw afterward cannot re-establish a square
hole in the crank because the retaining screw will break before the
spindle can exert sufficient stress to reshape the bore. Beyond that,
the crank would split before any plastic deformation could occur even
if the screw were sufficiently strong.

Because retaining screws could become entirely lose from squirming
action, especially if the press is relatively light, "dust caps"
should be used to prevent screws from subsequently unscrewing and
causing crank bore failure. Besides, the loss of the screw won't be
noticed until the crank comes off, long after the screw fell out.

The argument that the greased spindle will enlarge the hole of the
crank and ultimately reduce chainwheel clearance is also specious,
because the crank does not operate in the plastic stress level. At the
elastic limit it would break at the attachment knuckle in a short time
from metal fatigue, that occurs rapidly at the yield stress. In fact,
the depth of engagement (hole enlargement) can increase with an
unlubricated fit faster than with a lubricated one, because
installation friction is the only mechanism that reams the hole.
  #10  
Old January 28th 05, 11:17 PM
KD
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On Thu, 27 Jan 2005 23:44:09 GMT, "H. Guy"
wrote:

now, before i put the record on i thought i'd check and see
if this is a common complaint with ultegra octalink, and if
it's at all curable without resorting to method (1) above every
couple of months.


I have a Utelgra 9 sp tripple in my Litespeed. I've had some noise in
the BB, cured with Teflon(r) tape. I do grease the splines, but I tend
to grease everything as a matter of course. No other noises I've
noticed.

With all the broken crank threads lately, I'd take a really close look
at that crank arm.

Ken
 




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