Bicycle chains, with more than 400 individual parts, are a critical (though often neglected) drive train component. Wippermann’s Connex chains wear longer than other competing chains, but many people don’t have a clear idea of how chains wear, or even how they’re assembled. The purpose of this document is to explain how chains are made and why Wippermann chains wear longer.

Chain Component Parts

All bicycle chains are comprised of inner links (two inner plates that carry two rollers) that are connected, in sequence, to outer links (two outer plates joined with pins that pass though the collars of the inner plates).

As the chain is pulled over sprockets or the chain ring, the inner link rotates on a pin that is riveted to the outer plates. Chain wear is caused by friction between the pins and the inside of the collars on the inner plates. As these parts wear, the bearing diameter of the pin is reduced, and diameter of the collars increases. The result is that the measured length of the chain increases. This is called “chain stretch”.

Worn chains wear chain rings more quickly than new chains because a worn chain puts most of its tension on the first engaged tooth rather than distributing it more evenly over all the teeth. This is easy to see. With a worn chain, when you apply pressure to the crank, only the first few teeth at the top of the chain ring will be under tension; you can still easily lift the rest of the chain off the chain ring.  Rather than the chain’s tension being evenly distributed over the engaged teeth, most of a worn chain’s tension is focused on the first few teeth. The more the chain is worn, the worse this situation becomes. Focusing tension on just a few teeth chain dramatically increases wear on those teeth. The situation is exactly the same with driven sprockets.

Rollers do not wear appreciably, nor do inner or outer plates. The only wearing parts that affect the performance of the chain are the pins and the interior of the collars on the inner plates.


Why Wippermann Chains wear longer than other chains.

Pin Polishing

There are four principal reasons why Wippermann chains wear longer than chains.

Pin material. The pins Wippermann uses are boron-hardened steel. This makes them harder so they last longer. Other chain manufacturers use chrome-plated steel. While this is cosmetically

attractive, the boron-hardened steel used by Wippermann wears better.

Pin polishing. Wippermann polishes their pins so that their surfaces have less than 1.5 μm roughness (1 μm, a micro meter = 1/1000 of a millimeter). With a smoother surface, there is less abrasion between the

hardened pin and the interior surface of the inner link collars. Less friction = less wear.

 


Engineering

Collar diameter uniformity. In the same way that polished pins reduce wear points between the pins and the collars,

collar diameter needs to be uniform throughout the collar to

keep friction between the pins and the collars to a minimum.

Again, less friction = less wear.

Materials. Wippermann uses only high-quality steel and, on their top chains, stainless steel to ensure long wear. For the stainless chains, only the inner links are stainless (remember, the only wearing parts are the collars of the inner links). The result is a chain that wears up to three times longer than competing chains in the market.

 


Beyond Wear…

Notice the straight profile of the outer plates of Wippermann Connex chains. The inside is deeply chamfered to facilitate the quick engagement of sprocket teeth during shifting. The straight profile of the outer plate facilitates quick and quiet shifting.

Wippermann Connex Chain

For additional information about Wippermann Connex chains visit: http://www.cantitoeroad.com/connex

Or call: Cantitoe Road: 1.800.422.2104


Chain Flex

Sidebow checkOptimal shifting performance is achieved when the lateral flexibility of the chain falls within certain DIN norms. The test, called “Sidebow” requires that 1 meter of chain (79 links) laid on its side and lifted from the center will measure between 720 and 750mm for optimal shifting..

Too little sidebow (an overly stiff chain) results in poor shifting response; the derailleur can’t easily push the chain from one cog to the next. Too much sidebow (an overly flexible or worn chain) and the derailleur can’t push the chain accurately because there is too much flex between the jockey wheel and the cog.

 

 

 


Torsion…

Torsion CheckAnother critical component is torsional rigidity. Again, as with side bow, optimal shifting requires a balance of torsional rigidity. Wippermann’s test equipment is shown below.

Too little torsional rigidity makes the chain harder to shift. Too much and you risk that the chain twists so much during down shift (from the large to small chain ring) that it won’t fall properly onto the small chain ring and it drops (chain suck).

For additional information about Wippermann Connex chains visit: http://www.cantitoeroad.com/connex

Or call: Cantitoe Road: 1.800.422.2104

 

 


Chain Wear Test Results Point to Wippermann

Wippermann is conducting chain wear tests to quantifiably measure the wear rates of all bicycle chains on the market. The testing is performed on a test rig with a 52-tooth front ring and a 17-tooth rear cog.  All tests are conducted with a chain tension of 300 Newtons.  For each test, 128 links are used: 63 links of the chain being tested, 63 links of Wippermann chain, and 2 Connex connector links to join the chains.  The DIN reference length for 63 links is 800.10 mm.  The test begins with the length of each subject chain being measured (the actual length of new chains varies by as much as 1.2 mm among the various subject chains).

The test is conducted in 4 phases.  Each phase will be laid out below.

chain test

Wippermann’s 10sX chain with stainless steel inner links underwent 114 hours of this test before it showed 1% wear, considerably out-wearing all competitor chains tested to date.

youtube image

 View the chainweartestvideo and the completeresultsgraph (updated June 10, 2010).

Phase 1

The test begins with each chain undergoing a 5 hour run-in with its original lubrication under a 300 Newton load at 50 cycles per minute with the front and rear cogs in line with each other.  After 5 hours, each chain is cleaned and measured.  To measure each chain, one end is fixed in the rig and the other end loaded to approximately 1% of breaking load.  Some subject chains displayed measurable wear even after only 5 hours of testing!

Phase 2

During this phase of testing, the front and rear cogs are offset 5 degrees to the left to approximate maximum cross gearing.  With the chain running under a 300 Newton load at 50 cycles per minute, water is applied, then oil, and finally sand.  After 5 minutes at 50 cycles per minute under a 300 newton load, the cycle speed is increased to 100 cycles per minute under a 300 Newton load for 10 hours.  At the end of the 10-hour test period, each chain is cleaned and measured, and its length recorded.

Phase 3

Water, oil, and sand are again applied again during phase 3.  The front and rear cogs of the test machine are offset 5% to the right to approximate maximum cross-gearing in the other direction.  Again, after a 5-minute run-in period at 50 cycles per minute, the speed is increased to 100 cycles per minute under a 300 newton load for 10 hours.  After the end of the 3rd phase, each chain is again cleaned and measured, and its length recorded.

Phase 4

The application of water, oil, sand is repeated and each chain is run at 100 cycles per minute with the front and rear cogs in-line for 15 hours. At the end of this phase, each chain is again cleaned and measured, and its length recorded.  This fourth phase test protocol, with the front and rear cogs in-line, is repeated every 15 hours until the subject chain shows 1% wear, which is to say a measured length of 808.1 mm, 8 mm longer than the DIN standard. At this point the chain is considered worn out.

Results for: Connex, Shimano, Campagnolo, SRAM, and KMC

Wippermann’s 10sX chain with stainless steel inner links underwent 114 hours of this test before it showed 1% wear, considerably out-wearing all the competitor chains tested to date. So far 10 speed chains from Shimano, Campagnolo (campy), SRAM, and KMC have been tested.

Want to know how all the chains stacked up? Check out our chain test results page.

These chain wear tests are on-going, and updates are posted to our chain test results page as they become available.

To view all available Connex chains by Wippermann, and read customer reviews please visit our online Connex catalog.