From: BRANDT_JOBST/HP1900_01@HPLOMG.HPL.HP.COM
Newsgroups: rec.bicycles
Subject: Re: cleaning and lubricating a chain
Date: 27 Jul 92 03:38:15 GMT

It seems that reading the FAQ file is not high on the agenda of
the "chain letter" members, otherwise I don't believe there would
be so much repeated verbiage.  I might add that freewheels being
made of metal won't dissolve in hydrocarbon or most other available
organic solvents so there should be no concern for the freewheel.

From what I have read, it seems that many of the suggestions must
be from riders whose chains are not exposed to wet roads or dirt
roads, otherwise the use of solvents like WD40, Triflow, and wax
would not get a favorable review.  None of these "lubricants" are
recommended in any lubrication technical publication for this or
similar use.  Wax is not mobile and cannot replenish an interface
from which it has been mechanically displaced.  It does not bond
to the surface so it can be easily chipped off a surface leaving
practically no residue.  All tests with wax that I have made and
observed resulted in a squeaky chain upon the first contact with
moisture or a few miles of climbing, whichever came first.

In all the lubrication journals that I have seen I have never seen
canning paraffin or its derivatives mentioned.  I find its only
redeeming value to be cleanliness, but I can get that without any
lubricant.  It does not prevent rust in the longer term since it
chips off the outside from shifting.  If it could perform this task
maybe the painters of the Golden Gate bridge should be alerted to
this method.  They spend huge sums of money on weather resistant
paint that must be replenished often.

jobst_brandt@hplabs.hp.com

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Item Subject: Chain lube
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Chains


Lubricating Chains

Lubricating chains is a somewhat religious issue.  Some advocate oil,
some Teflon-base lubricants, some paraffin wax.  The net majority favors
a lubricant that does not leave an oily coating on the chain that can
attract dirt, which will hasten chain/chainring/freewheel sprocket wear.

If you want to use paraffin wax, make sure you melt the wax in a double
boiler!  Failure to do so can lead to a fire.  You can use a coffee
can in a pan of boiling water if you don't want to mess up good cookware.
After the wax has melted, put the chain in the wax and simmer for 10
minutes or so.  Remove the chain, hang it up, and wipe the excess wax
off.  Let it cool and reinstall on your bike.

When using a liquid lubricant, you want to get the lube onto the pins
inside the rollers on the chains, not on the outside where it does little
good.  Oilers with the narrow tubes are good for this because you can put
the lube where you want it.  Work the oil into the chain after applying
it, wipe the chain off, and reinstall on your bike.

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Wear and Gear Slippage  (Jobst Brandt  jobst_brandt@hplabs.hp.com)

There seems to be a lot of speculation on what makes chains wear
and how to lubricate a chain.  There are a number of ways to take
care of a chain.  Some traditional methods are the most damaging
to chain life and others work to prolong life.

As was mentioned on the net, chains don't stretch in the sense
that the metal elongates, but the parts wear.  Wear in the pins
and sleeves change the length of the chain as the pins fit more
loosely.  The wear arises primarily from road grit that enters
the chain when it is oiled.  Grit on the outside of a chain looks
bad but it has no effect on the function because it can't get
inside to do damage.  Only when a dirty chain is oiled does this
grit get to the place where it can cause damage.  Note that
commercial abrasive grinding paste is made of oil and silicon
dioxide (sand) and silicon carbide (sand).  You couldn't do a
better job if you tried to destroy a chain than to oil a road
dirt (previously oiled) encrusted chain.

Primitive rule #1:  Never oil a chain on the bike.

This means you should clean the grit off the chain before oiling
it.  Because this is essentially impossible without submerging
the chain in a solvent bath (kerosene or commercial solvent), you
must take the chain off the bike.  The fine grit can only be
removed from the interior of the chain in liquid suspension.  A
good example of this can be seen by using a Vetta (on the bike)
chain cleaner and subsequently cleaning the same chain in a
solvent bath.  The best grit remains until last and there's
plenty of it.

Removing the solvent from the chain after the rinse is important.
Compressed air is not readily available in the household nor is a
centrifuge.  You can go outdoors and sling the chain around.
This works best if the chain is a closed loop.  You don't have to
press the pin completely in for this.  The other way is to
evaporate it.  You should probably avoid accelerated drying
methods because they could be explosive.

The hot gear lube method works but it also acts as efficient fly
paper, collecting plenty of grime between cogs.  Motor oil is good
but motorcycle chain lubes are better because they have volatile
solvents that allow good penetration for relatively viscous
lubricant.  Paraffin is useless because it is not mobile and
cannot replenish the bearing surface once it has been displaced.

Sedisport

The Sedisport chain, although the strongest and one of the
lightest chains, achieves its light weight at the expense of
durability.  This chain has omitted the sleeve that on most
roller chains supports the roller on its outside and furnishes
the bearing for the pin on the inside.  Normally the inside of
the sleeve is well protected against lubricant depletion because
both ends are covered by closely fitting side plates.  In the
Sedisport there is no sleeve and the formed side plates support
the roller and pin with a substantial central gap.  In the wet,
lubricant is quickly washed out of pin and roller and the inferior
bearing for the pin and roller often gall and bind.  In good
weather this is not a problem.  Because this chain has feet of
clay in the wet, Sedis re-introduced their earlier 5 element
conventional chain, calling it a "chain for all seasons".

The lightweight Regina chain goes one step farther and omits the
pin, leaving the side plates to hinge directly on the sleeve.
This gives them a knife edge bearing area that galls at the
slightest lube depletion.

Chain Life

This is almost entirely a cleanliness and lubrication question
rather than a load problem.  The effect of load variations is
insignificant when compared to the lube and grit effects for
bicycles.  The primary chains on motorcycles are operated under
clean conditions and last years while the exposed rear chains
must be replaced often.

The only way to test whether a chain is worn is by measurement.
The chain has a half inch pitch and, when new, has a pin at
exactly every half inch.  As the pins and sleeves wear this
spacing increases and becomes damaging to sprockets.  When the
chain pitch grows over one half percent it is time for a new
chain.  At one percent chainring damage progresses rapidly.  By
holding a ruler along the chain on your bile, align an inch mark
with a pin and see how far off the mark the pin is at twelve
inches.  An eighth of an inch (0.125) is the ten percent limit
while more than a sixteenth is a prudent time to get a new chain.

Skipping Chain

When you put on a new chain, its pitch is exactly one half inch.
A sprockets worn by a longer pitch chain pockets in its teeth.
These pockets are formed by the rollers of a worn chain as they
exit the sprocket under load.  Rollers of a new chain with
correct pitch exit under no load because the load is transferred
to the next roller before disengagement.  However, with hooked
sprockets the new chain cannot engage under load because the
pitch is too small to get over the hook and into the pocket.
These differences are only a few thousandths of an inch but that
is enough to prevent engagement when the previous roller is in
its pocket.

As a chain wears it concentrates more of its load on the last
tooth of a sprocket before disengagement because its pitch no
longer matches the pitch of the sprocket.  This effect sometimes
breaks off sprocket teeth.  The load concentration on the
sprocket also accelerates wear and is another reason to replace a
chain at 1/16th inch wear.

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