Questioni have a 93 katana 750 and a 91 cbr600f2 i was woundering is re-tension of the chain necassary with milage each bike has about 29000 miles on them
AnswerHi Don,
Keep your chains adjusted and lubricated. Always replace chain and sprockets as a set when necessary. Read the following file:
Respectfully,
Mark Shively
Chain Maintenance
Neglecting your chain is kind of 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 unlubed 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 relubricate 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 are 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 it's 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 uncentered 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!
