The Great Chains of Being

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Wax-based chain lube, a quick link and a chain tool

The Great Chains of Being
When was the last time you heard another rider bragging about their new chain?
Bicycle chains are usually anonymous. Unnoticed, almost invisible… Until the chain breaks or slips off and then the chain is all you can think about!

Yet, when asked what item he monitored and replaced regularly during the 3000 mile Race Across America, a mechanic answered, "chains." For the regular rider and the avid racer, chains should be looked upon as the oil in an automobile: They should be replaced at regular intervals, as continued use of a worn chain will cause losses of efficiency and reliability.  

Disassembled inner chain link with rollers

The riveted joint roller chain is a marvelous drive system. Although made of stiff individual links and rollers, the multiplied combination of those rollers and links allows the chain to bend and flex enough so as to allow easy shifting yet be strong and stiff enough to pull cleanly and evenly against the teeth of chainwheel and sprockets. When new, clean and lubed properly a bicycle chain can achieve power transmission efficiencies of 88-99 percent. (Bicycling Science, David Gordon Wilson. 3rd Ed. Pg 342)   

Everything Sags With Age
However, due to wear accumulating at each riveted joint, the whole chain grows longer with usage and drive efficiency suffers. This, "stretch" at each joint will cause the chain to ride unevenly against a sprocket. When observing this unevenness of the chain on a sprocket you will notice that the first and second links mesh properly, but by the time the third, fourth and fifth link follow along and contact their matching teeth they do not seat fully against the teeth. This can lead to premature tooth wear and possible tooth breakage because there are fewer teeth bearing the same amount of power transmitted from the chain. Periodically check your chain and be prepared to replace it at regular intervals.

Also note that with the advent of bike cassettes with more than 8 speeds, that chains have become thinner and thinner to accommodate the increase in the number of sprockets on the cassette. Although the jury is still out on the long term reliability of the newer 9,10 and 11 speed systems it seems to me that the more material you remove from any structure, chains included, is going to reduce it's life span and reliability. (11 Speeds? The rider/engineer in me is shouting, "Now was that really necessary!?" If one day the component makers come out with an 10 speed 11-44 toothed cassette, I might buy into a new chain system to eliminate the front/top derailleur, but until then….)




Be a Chain Tool
The three basic chain tools: (1) Chain Tool (aka chain breaker) such as the Park CT-5 or CT-3. (2) Masterlink pliers such as the Park Tool MLP-1. These will help speed removal of quick links/master links, especially for those with dexterity issues. (3) Chain wear measurement tool such as the simple Park CC-3.2 chain wear indicator will help determine when to replace a chain.

Disclaimer: Although I do like most of the Park Tool product line and use some of their tools I do not use their tools exclusively nor do I receive any compensation from Park. Having personal experience in fields such as automotive, plumbing, small engine, welding and electrical I must say that Park Tool makes a very good tool. Tools by Spin Doctor are an economical choice although the product line is not as broad or as widely available as Park.  

Lube
There are a few opinions about the type of lube to use on a chain. Most chain manufacturers like to ship chains lightly coated in thick paste-like grease. While good at protecting the chain from rust, this factory lube tends to attract and trap dirt and road grime very quickly. This writer prefers a drier wax based lube as it offers the rust protection of grease but does not trap as much dirt. Regardless of your choice of lube, you need to thoroughly clean/cleanse the chain of the old dirt and grease before re-lubing a chain. Chain cleaners, solvents and lubes can be found at your local bike shop. A chain can be cleaned while on the bike but the easiest way to clean and lube a chain will usually be to remove it from the bike to clean it.

Frequent Rider Maintenance Tip:

Having two or three spare clean/lubed chains on hand can simplify chain maintenance: You can remove the old chain from the bike, drop it in a solvent bucket, grab a fresh chain and install it, letting you clean and re-lube the old chain when it is convenient.

New Chain Installation on Upright Bikes
If you have your bike's original chain handy, count the links and then count off the same number on the new chain to break it at the right length. If you do not know the original link count and are not trying to modify the chain length do the following:

The Add Two Links Rule
Wrap the new length of chain around the largest chainwheel and largest cassette sprocket without threading the chain through the cassette derailleur. Add two links to the overall chain length and break the chain.

A quick link/masterlink can be added to complete the final chain installation and will allow for quick chain removal. Note: masterlinks and quick links should also be monitored for wear and replaced at intervals. The easy serviceability of the quick link also means the quick link wears faster.

Chain Length and Handcycles

Compared to a bicycle a handcycle usually has abnormal distances and angles between the cassette and chainwheel as well as an extreme gear ratio range and a long cage style cassette derailleur that rides upside down. The result is that the typical handcycle has a very long chain and a bouncy derailleur.

This extra chain length can allow the chain to bounce a lot on rough pavement and that can sometime contribute to unpredictable shifting or in rare cases allow the cassette derailleur to bounce dangerously downward toward the cassette teeth. This is the nature of the beast and there is not a lot that can be done to overcome the problem. However, a properly fitted chain can keep the chain only as long as it needs yet be long enough to move freely at either extreme of the shifting spectrum.



Measuring to fit a chain to a handcycle is no different than fitting a regular bike and most times the, "add two links" rule holds true. However some handcycle chains may require an adjustment of 1 or 2 links of chain to prevent the cassette derailleur from locking up when you shift the bike to either the two largest or two smallest gears. From riding experience we know that such shift combinations are really rare. But there are those times that you might find yourself hitting a bad series of bumps when you find yourself in your big ring and big cog and suddenly discover that the spokes on your front wheel just ate your shiny new SRAM derailleur! I should know. It once happened to…… a friend of mine. (Cough, cough.)

Long Ride and Racing Tip

The lightest chain related ride insurance for crucial races and road trips is a quick link stashed in an accessible location on the bike. (Under the end-cap of a hand pedal is my preference.) Even if a chain field repair makes your chain a bit shorter than normal and prevents access to some gear combinations, you should be able to make it across the finish line instead of having to hitch a ride home on the sweeper car. For some riders, accessing a chain to make repairs during a ride may be difficult. However it has been my experience that even in the midst of major events there can oftentimes be a bystander or fellow rider nearby more than willing to help with thrown or broken chains.