|
Chain Maintenance
Neglecting your chain is kinda like wearing
that ratty pair of leopard-skin underwear that normally remains buried in the
bottom of your sock drawer. Under normal circumstances, everything's fine,
you're cool and no one's the wiser. However, keep rolling the dice and
guaranteed, one day you're going to end up in the emergency room, scaring the
bejeezers out of some 17 year-old candy striper. We've seen this happen (the
chain thing, that is) all too often.
Met a novice rider on the trail at Green Marble several weeks ago walking
backwards (on the trail, that is), with his chain draped around his neck. Had a
sorry tale to tell about how his KDX's shift shaft was mysteriously sheared
clean off the bike, for unknown reasons. In an even stranger saga, a riding
buddy a couple of years back lost a brand new Arai MX-E up at the Canyon as a
result of chain failure, but that's another story. The theme here is, neglect
your chain and all-too-soon it's going to bite you in the derriere, one way or
another.
Naturally, the best way to avoid chain and chain related failures is through
regular inspection, adjustment and maintenance. Water, mud, and the like play
havoc on equipment, and chain is no exception. The steady diet of mud and water
that we typically see stresses the drive chain considerably more that those
bikes ridden in controlled and/or dry climates. No doubt things are better than
ever with the advent of o-ring chains, significantly reducing adjustment and
maintenance needs. However, not all riders opt for o-ring chains, and even
o-ring chains will last longer when treated right. Chain maintenance basically
boils down to cleaning, lubricating, tightening, alignment and replacement.
Accumulated dirt, old lube, crud and corrosion on your chain not only sows the
seeds of wear but causes more power robbing friction as well. The best way to
rid your chain of these contaminants is a thorough cleaning. The most thorough
method of cleaning is accomplished by removing the chain from the bike and
soaking it in solvent, like kerosene or diesel fuel. This works wonders for non
o-ring chains, but for o-rings, watch out. After a long soak, the solvents can
get inside of the o-rings and destroy whatever lubricant remains, while the
o-rings can confound your attempts to re-lubricate the chain. Best to just brush
off an o-ring chain with a stiff bristle brush, or at most wipe it down with a
solvent-soaked rag.
If your chain wasn't too dirty and you opt for cleaning while washing the rest
of your bike, be sure to lube your chain before the washing. Washing an un-lubed
chain allows water to creep and settle in between the various rollers, bushings
and pins. If you lube your chain afterward, the lube has the tendency to "seal
in" the water, further promoting corrosion. Speaking of lubrication, the only
thorough way to lubricate a chain is through immersion. Before o-ring chains,
astute riders used to remove their chain after every ride and soak it in a pan
of oil for several days. This allowed the oil lubricant to completely flow in
between the chain rollers, pins, and bushings. With the advent of o-ring chains,
a couple of things happened. First, many o-ring chain manufacturers used to
claim that they never needed lubrication. This just isn't true. While the
o-rings seal the pin/bushing junction, they do nothing for the chain rollers.
O-ring chain rollers still require regular lubrication for this reason, and to
ward off corrosion as well. Another rub with o-ring chains is that not only do
they seal in whatever lubricant was applied at the factory, but seal out any
attempts to re-lubricate the bearing surfaces afterward. In spite of this, the
immersion process will still provide superior lubricant coverage between the
chain rollers and bushings, and perhaps seep past more than a few loose o-rings
as well.
Spray on lubricants are by far the most popular these days, offering several
distinctly different options. They include silicon based sprays, WD40-type
cleaners/lubricants, traditional oil based chain lubes, and the new spray on
chain wax marketed by Maxima. Opinions regarding the merit of any of these lubes
vary greatly, however, we've tried them all and offer the following insight
based upon those experiences. Silicon based sprays, TFF, WD40 and CRC type
cleaners/lubricants became popular with the advent of o-ring chains. The theory
went that since the o-ring chains are lubed at the factory, all that was really
needed was a coating to repel dirt and impede corrosion. Silicon base sprays are
good at that, providing some lubrication for the o-rings themselves as well.
Problem is though that while o-rings seal the pin/bushing junction, the chain
rollers themselves remain unsealed and thus require lubrication. The other
sprays like WD40 and CRC perform along the same lines, except that these sprays
have solvents as well as lubricants and can be helpful removing dirt and old
lubricants. The bottom line, however is that chain lubed with these space-age
sprays has the tendency to wear out chain rollers, as the rollers never get
sufficient lubrication.
Traditional chain lubes are essentially oils with additives to make them
stickier, preventing the lubricant from flying off during use. They can provide
excellent lubrication of all chain moving components for both standard and
o-ring chains. The catch with traditional chain lubes is that not only do they
stick to the chains moving parts, but succeed in picking up and capturing dirt,
dust and sand at an alarming rate. This turns your chain lube into an abrasive
mixture of chain lube and crud not unlike valve grinding compound. Regular chain
cleaning can combat this scenario, however removing dried chain lube can be
among the toughest bike cleaning tasks. The newest and perhaps most innovative
chain lubrication is chain wax. Chain waxes provide a thick water and corrosion
blocking coating on the chain and within the various moving parts. The kick with
chain waxes is that once dry (after a few minutes) they're non-sticky to the
touch and therefore don't attract dirt like traditional chain lubes. To give you
some idea of our preferences, I typically use traditional chain lubes on our
test bikes and save the coveted chain wax for my personal scoots. Enough said.
Chain tightening and alignment is an important factor in getting the most life
out of your chain and sprockets. All chains stretch through the course of their
life span requiring occasional tightening to achieve proper free play. A general
rule of thumb is chains are stretched beyond useful service when the stretching
exceeds two percent of the original length (roughly a quarter inch for every
twelve inches of original length). There are numerous other methods for
evaluating a chain's condition, most more subjective than the above. As the
chain stretches, the free play or tightness must be adjusted. Generally, chain
free play should usually be approximately one half to one inch, up and down,
measured at the midpoint between the front and rear sprockets. The amount of
free play can vary, so its always best to consult your particular model's owners
manual. Be advised that chain wear and sprocket wear go hand in hand. If you're
seeing side wear on a sprocket, this is indicative of a chain misalignment,
which could be caused by the rear wheel being un-centered in the swing arm or
improper wheel spacers misaligning the motor and rear wheel. The most reliable
means of ensuring proper wheel alignment is to measure the distance between the
rear axle and the swing arm pivot bolt, on both sides. Even with the best
maintenance practices, some day a new chain will be required, as chain and
sprockets are consumable parts. Not surprisingly, it's always best to replace
chain and sprockets as a set. No doubt the longest service life is achieved when
all are replaced simultaneously, and conversely, the service life is reduced
whenever mating a new chain to used sprockets or vice versa. When choosing a new
chain a plethora of options exist. We'll not tout one brand over another,
however, some other rags have completed exhaustive strength tests of various
chains with (yawn) expected results. Basically, you get what you pay for.
However, for off-roading in eastern (read: mud, water, slime, etc.) conditions,
an o-ring chain will provide superior longevity. The only riders we know that
don't use them are those riding small displacement machines, where an o-ring
chain would rob already lacking horsepower.
A final aside on master links. This simple and inexpensive part is probably the
single greatest cause of chain failures and the damage associated with it.
Inspect your master link before every ride and replace it whenever it hints of
wear. For the price of a two dollar master link, you could very well save
yourself the hassle of removing your swing arm on the trail (to free your wadded
up chain) or even the cost of a set of cases!
By Mark Uth
Return
to Gnarly Parts and Accessories
|