T.R | Title | User | Personal Name | Date | Lines |
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788.1 | grease'em | MAILVX::HOOD_DO | | Thu Jul 21 1988 10:47 | 8 |
| I grease my crank arms, also. If I don't grease them, I find them
extremely difficult to remove. By the way, is there some kind of
puller for the crank arm with gears attached? A two arm puller wont
do it, but will a three arm puller take it off? I let the bike
shop deal with my freewheel. Do pedals need greasing? How does one
go about servicing pedals?
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788.2 | Oh yes, grease everything !, well, almost. | MENTOR::REG | Just browsing; HONEST, I'm BROKE ! | Thu Jul 21 1988 10:55 | 29 |
|
I grease just about everything but the chain and brake blocks.
I used to wax chains, but with the price of sedisport chains being
what it is I'd rather buy 'em by the six pack and chuck 'em at passing
jogg<ooops> when they get dirty.
Since getting into boat maintenance, sorta via water skiing,
I've been using marine grease on bikes and cars. It just DOESN'T
wash out, of course, even in salt water (also, 'OF COURSE'). It's
green and makes more mess on clothes than white lithium grease,
but I don't have enough grease guns to keep every type at hand,
so I'm using this stuff for everything, just have to be a bit more
careful about wiping off the excess. I assemble almost nothing
"dry", I use anti-seize on parts that will get hot, lock-tite on
parts that will get vibrated and don't have other adequate locking
mechanisms, grease on things like crank arms to BB spindles, teflon
tape on pipe threads, etc. The major rationale is ease of subsequent
disassembly and lubrication to get the parts "on tighter" with less
force. Most recommended torque settings ASSUME clean and lubricated
threads and tapers (crank spindles, magneto flywheels, etc.).
It isn't being "fussey" to run bolts through a die or a tap through
threaded holes to clean off old thread-lok, its the ONLY WAY to
get accurate torque settings.
Reg
{and yes, Al & Fe DO have a tendency to grow together, especially
in the presence of air and moisture, salt makes it even worse}
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788.3 | No! don't grease the crankset that way! | SSDEVO::ACKLEY | wow | Thu Jul 21 1988 10:57 | 25 |
| Grease the seatpost and non-sealed wheel bearings, headset
bearings, bottom bracket bearings, derailure pulleys....
The *one* thing you dont want to grease is the crankset axle
where the crank arm attaches!! At least with expensive cotterless
cranksets with aluminum crank arms, this is a big mistake! If
you grease this surface, you can then draw the crank arm on too
far with the bolt that goes into the end of the axle. If you
do this, the worst case scenario is that the aluminum crank arm
expands, so that it rides too close to the frame, or even scrapes.
That crank arm's life can be measured in terms of the number of times
you take it on and off. When you grease it, that number of times
you can extract it goes way down.
Some old cranksets are particulary finikey in this regard,
like an old Stronglight I had that could only live through three
or four extractions before needing a new crank arm. Most other
cranksets are much better, but can still be damaged if you grease
those surfaces and then draw that bolt too tight.
Alan.
PS: The above only refers to 'cotterless' cranksets. Cranksets with
only one flat side on the axle surface, that have a 'cotter pin'
to hold the crank arm on, can be greased.
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788.4 | Grease packed freewheels are quiet, don't let water in either. | MENTOR::REG | Just browsing; HONEST, I'm BROKE ! | Thu Jul 21 1988 11:05 | 13 |
| re .2 .1 reminded me, I built a freewheel grease injector
from an old hub. I also have a bearing greaser that works well on
freewheels, though the cogs have to come off to use it, no problem
since everything needs cleaning up around then anyway. I havn't
tried the marine grease in a freewheel, but don't see why it wouldn't
work well.
Pedals are easy, well conventional pedals are, dunno about the
funny_foo_foo,_no_parts_available,_but_they're_sealed_for_life stuff.
Just strip everything out, clean, grease and reassemble.
R
|
788.5 | Careful where you lube | AKOV11::FULLER | | Thu Jul 21 1988 12:13 | 12 |
| I agree with .3, don't grease the BB axle to the crank for the reasons
mentioned. The generally recommended way of "lubricating" this
area is to wipe the end of the axle with your hands. The oil from
you hand will have sufficient oil to keep the crank and bottom bracket
from forging together.
Another area that needs lubrication heavily is the stem in the head
tube. Besides allowing for easy removal, it may quiet any noises
in this area.
steve
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788.6 | Early design/spec problems continue to cloud the problem, there is no problem now. | MENTOR::REG | Just browsing; HONEST, I'm BROKE ! | Thu Jul 21 1988 13:17 | 27 |
| re .3 The old Stronglights had a spec confusion problem.
For a while it wasn't clear who (other than Campy, who started an
industry "standard" by default around '53) was making crank arms
for which spindle taper. There was a lot of pseudo_technical
discussion around about the taper in the crank arm needing to be
a degree or two greater/less than or equal to the taper on the spindle.
A lot of crank arms were literally split at the eye end by mismatch
of taper, log splitter sort of effect. All of this lead to very
poor acceptance of "cotterless cranks" for a long time. Now that
the standards are all sorted out (see Southerland's) it can be safely
assumed that these bicycle parts are subject to all the regular/normal
laws/rules of physics and engineering. {Of course those laws were
never suspended, the parts were adhering to them totally as they
broke/wore out prematurely.}
<Translation: Grease as for ALL tapered assemblies.>
Reg
{BTW, The term "Axle" is generally used for parts that carry
rotating parts, the axle itself doesn't rotate.
The term "Spindle" is generally used for parts that rotate
WITH other parts attached to them.
Hence bicycle wheels have axles (that don't rotate), whereas
bicycle bottom brackets have spindles (that do rotate). }
|
788.7 | can happen even with good specs; | SSDEVO::ACKLEY | wow | Thu Jul 21 1988 17:23 | 19 |
| RE: .6
Admittedly most cranksets are better than the old Stronglights,
but even Campys' can have this problem if you grease the spindle
and take it on and off a few times a year. Particularly the left
crank arm, which has less metal around it than the right. A few
years back I had a 15 year old Campy crankset that had to have that
one crank arm special ordered for replacement, due to this type
of expansion. After many years of coming on and off, the crank
arm just went all the way on, so that the bolt would be flush
against the end of the spindle and the crank arm would still be
loose.
This was probably an unusual type of damage though. That
crankset had been on two previous bikes and had been raced by
two oversized (200 lb++) sprint 'monsters', before I got it.
When I ordered the new crank arm, the best bike mechanic I know
told me to *never* grease those surfaces.
Alan.
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788.8 | Campag's view? | RDGENG::MACFADYEN | Roderick MacFadyen | Wed Aug 31 1988 07:53 | 5 |
| I got a Campagnolo chainset and bottom bracket recently. The whole
BB spindle (to use the approved terminology) came coated in a thick
grease. Does this show Campagnolo's view on the matter?
Rod
|
788.9 | no | NOVA::FISHER | BMB Finisher | Wed Aug 31 1988 08:26 | 2 |
| I don't think it means anything. Many metal parts are stored with
coatings of grease just to protect them from corrosion.
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788.10 | When is a grease no a grease ? | MENTOR::REG | Just browsing; HONEST, I'm BROKE ! | Fri Sep 02 1988 11:05 | 8 |
| re .8 Sure it was grease ? I thought they used something
more like "Cosmeline" (sp ?) which is sort of a very thick version
of WD-40.
Reg {who still believes that these tapers are no different to
any others}
|
788.11 | That's a good question... | RDGENG::MACFADYEN | Roderick MacFadyen | Mon Sep 05 1988 05:46 | 9 |
| Re last (Reg):
I wouldn't recognise Cosmeline if you threw me in a barrel of it, but
the stuff on the BB spindle was brown and gooey, so I assumed it was
grease. When I put the cranks onto the spindle, they went on very
smoothly, so I didn't use all my force to tighten the bolts. Does
that seem sensible?
Rod
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788.12 | A much-belated entry in the discussion | SMURF::BINDER | And the quarterback is *toast*! | Thu Nov 03 1988 14:44 | 35 |
| Re: assorted. FWIW, this comes from a former professional bike
mechanic. I spent several years in that business.
Nobody bothered to answer the question in .1 abuot pullers. There are
pullers specifically made for crank arms. The puller consists of a part
that screws into the arm using the dustcap threads, and another part
that screws through the first one like a bolt through a nut. You take
out the crank bolt, screw the puller in place, and then screw the inner
part against the spindle to force the crank arm off. Bike shops should
have these - Park makes a "universal" one, and most crank makers have
one that fits their own (and sometimes some other) cranksets.
As to the initial question, i.e., grease or not, .3 is right. *Don't*
grease cotterless crank tapers. Reg, the reason this is different from
all the other tapers is that it is almost unique in having aluminum
pressed onto a square steel taper. The marked dissimilarity in
mechanical properties will cause a greased crank taper to fail
eventually, for the reason described in .3. I know, I've been there.
Once. What actually happened to me as the crank was drawn on too far
was that the crank split, just as if I'd been using a commercial
nutcracking tool. It was a Sugino crank on a Sugino spindle.
About 13-15 years ago, Nervex made some steel cotterless cranks. These
had to be greased, or the crank would never go on far enough to keep
from loosening. But almost nobody understood the problem, and the
product died rather quickly. The last bike I know to have used them was
the '75 Raleigh Super Course.
If you're dealing with cottered cranks, then it's okay to grease the
crank and spindle, but *don't* grease the flat, the cotter hole, or the
cotter itself. It's not the nut on the cotter that holds this assembly
together - the cotter is supposed to be *pressed* in before the nut is
assembled on, and friction is the order of the day.
- Dick
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788.13 | A follow-up entry | JUMBLY::MACFADYEN | iller still | Tue Jun 06 1989 14:22 | 21 |
| I'd just like to say that experience has now taught me that the advice
contained in .3, .7 and .12 is totally correct - don't grease
cotterless cranks.
The LH crank of the bottom bracket I referred to in .8 (I think)
continually went loose after every tightening (I had assembled it with
the grease that was already on it). I got sick of this a few weeks back
and did what I should have done in the first place; remove LH crank,
clean all the grease off the flat parts with white spirit, use a bit of
nose-grease to hinder any corrosion locking problems that might occur,
and re-assemble. During 200 miles since then, no problem.
This is a Campy Triomphe crankset, and it does illustrate a
problem/feature with Campy cranksets that I think has been aired in
other notes - this is that the LH crank sits very close to the bottom
bracket cup. No doubt exacerbated by my incorrect assembly in the first
place, the crank now has a millimetre or less of clearance. Am I right
that Campy cranksets are often like this?
Rod
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788.14 | campy crank, left arm too close; | AHOUSE::ACKLEY | Mediumfoot | Tue Jun 06 1989 18:30 | 40 |
| RE; .13 Rod,
> This is a Campy Triomphe crankset, and it does illustrate a
> problem/feature with Campy cranksets that I think has been aired in
> other notes - this is that the LH crank sits very close to the bottom
> bracket cup. No doubt exacerbated by my incorrect assembly in the first
> place, the crank now has a millimetre or less of clearance. Am I right
> that Campy cranksets are often like this?
This was one of the problems I had with the super record campy
crankset I had described in .3. In my case, the clearance was
so close that occasional bits of gravel would get in the crack
and scrape things up. I discussed it with the pros, and they
thought at first that I had ruined the LH crank arm by drawing
it on too far. Rather than order a new one, we sanded off the
little lip, on the inside of the cranck arm, which had about 2 mm
to spare, thus adding that much clearance. I then used it
that way for several years, so it was an effective fix.
Then later during a rebuild, we checked the specs and discovered
that the wrong spindle had been installed! There are many sizes
of campy spindles available, and the one I had was just too short
on the left side of the bike. It must have been a mistake caused
by confusing the various diameters, and threads used by Italian,
French or English bikes. This was a Swiss bike and no one knew
what was supposed to go on it. Installing the correct spindle
was the *real* fix, in my case. It turned out there had really
been nothing wrong with my crank arm, and it doesn't seem to
miss the gram we sanded off. :-)
Hope this helps you some. I don't think it's *normal* to
have such a clearance problem. When we were fixing it, my mechanic
friend said; "At first I thought your [ ? ] was in backwards,
as that happens a lot on these campy cranksets..." It may be
that the spindle or the cups could be in wrong, or backwards,
to cause some misalignment. In my case, I'd have never found
it without the help of a friend who looks at lots of these
campy cranksets, and knew what to look for.
Alan.
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