Tuesday, January 10, 2012

Paracycling Repair Resources Online

Posting the previous articles has brought to mind the many online resources that this writer has found helpful. Many paras have very customized rides and so finding maintenance information or parts at the LBS (local bike shop) to make repairs can be difficult. If you have not already used the sites listed among the links below, have a visit. You may be surprised at the amount and quality of information that is out there. As with all areas of life, the internet has made for an abundance of information. Oftentimes all you need do is google a part number and you will find your answer.

Handcycle Non-Standardization

As a result of running some very extreme gearing the handcyclist may end up riding with a motley array of hardware: SRAM long cage front/bottom derailleur. A SRAM or Shimano cassette while running a completely customized chainring combo that is shifted with a chainring derailleur actuated directly by a hand operated lever bolted to the derailleur itself. Add to this mix such things as rider dexterity issues or personal preferences that drive the choice of shifters and you have a component stew that can give an inexperienced local LBS "wrench" nightmares!
The typical local mechanic knows very little about such setups and so for the handcycle owner, doing research online about components and setup is key before going to the shop. It may seem odd or even offensive to some riders to tell a mechanic or salesperson what is needed but that is often what is required! However, the better and more experienced local mechanics have usually heard of a handcycle even if they have not worked on one. This blogger knows of a very experienced mechanic working at a national bike store franchise who has done team support for handcycles. It is unusual but once in a while you do find a rare gem of a mechanic. Get to know them, tip them generously when you use their services, as they are sometimes your best resource even if you do your own repairs.


Informative Maintenance Links

The following is a compilation of web resources that have been of help in figuring out service procedures, parts compatibility and adjustment. If any readers have other suggestions I will gladly add them to later edits. Email me at: g_damerow(at)yahoo.com
 
For very helpful, well-illustrated and detailed service procedures on just about every brand and type of bike component out there, Park Tool:

http://www.parktool.com/blog/repair-help

Among the major three, (Shimano, SRAM and Campagnolo) Shimano has the most comprehensive documentation available. Want to know the largest chainring size that will work with that E-type bottom bracket mounted front/bottom derailleur? Google the part number and Shimano will have it.

http://techdocs.shimano.com/techdocs/index.jsp

SRAM also has a support section on their site. Not as comprehensive but still contains useful information.

http://www.sram.com/service/sram/all

For those Campy Cultists there is the very refined looking service section of the Campagnolo website. (Campy Cultists. Uh oh. Here come the comments. A question to ponder: What if Steve Jobs had worked at Campy and not Apple?)

http://www.campagnolo.com/jsp/en/doc/doccatid_1.jsp

By the end of his life, Sheldon Brown was probably so saturated with bike knowledge that he had sprockets where his brain should have been! Sheldon was known for his innovative and non-standard thinking and for using unusual combinations of parts and components. (Example: His his 63 speed bike. http://sheldonbrown.com/otb.html) Such outside-the-sprocket thinking is sometimes just what you are looking for as a para bike mechanic. If you are in need of strange and unique information or tips on unusual components Sheldon's site will probably have it. The site is now maintained and updated by his friends over at Harris Cyclery.

http://www.sheldonbrown.com/


Two other sources of basic information on parts and part compatibility:

http://www.ebay.com

http://www.amazon.com

No, that was not an error! Often sellers will list a part or component by part number reference and to better inform the buyer on compatibility, the seller will list what the component will and will not work with. Not all information is reliable or applicable to some setups but one component listing often leads to another and then you find out the information you need. Ebay has a very good search engine and can oftentimes narrow down the search faster than google alone.

Lastly, I have posted all of the above major links in my "links" box at the upper right side of the blog for future reference.







 

Thursday, January 5, 2012

The Great Chains of Being


During the last weeks of December 2011 I was a semi-finalist in the Hartford Achieve Without Limits contest. The finalists are to be announced in January 2012. Thanks to all the blog readers who voted!


http://www.facebook.com/TheHartford?sk=app_258066527550278 





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.