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Old 05-01-19, 10:06 AM
  #163  
cyccommute 
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Originally Posted by base2 View Post
Here

If you followed the link to the other chain lube thread, the link was provided in the first sentence of the first post.
The link in the other post didn’t work.

Having scanned the paper...it’s rather long...I have some interesting observations. First, the chart that you is only part of the story. Yes, the wear measured in the paper was less for the thicker oils. However, the other side of the story is told in the chart shown in Figure 3.2: Coefficient of friction results and corresponding power loss values for common bicycle chain lubricants. (I can’t seem to cut and past the chart). The oils that gave the least amount of wear also gave amoung the highest wattage loss and highest coefficients of friction.

Additionally, the wear measurement is made in clean laboratory conditions, which is stated in the conclusion of the paper. It appears that the “future work” has not been performed as of yet. Adding in grit and dirt should drastically change the results.

BTW: Humans can generate a huge amount of peak torque. 100 kilos standing on a 175mm crank arm is 175 newton meters of torque. Multiply that times 100 rpm...That's close to 2.5 horse power if it were sustained for a sprint. (Yikes) But figure in 1500 watts (2 horse power peak) times 1 crank revolution...Like a BMX race, for example. Thats North of 14,000 Newton-meters. Now divide that by the area on the side of the pin in the link that actually takes the load. The force the lubricant must resist (14,000 * .5=28,000) An incredible amount of force, indeed.
But that is transient peak force which has little effect on the wear of the chain. More normal wear is going to be a fraction of that. Even the peak force is a tiny fraction of what you would expect on a similar chain when used in a motorcycle with even a modest engine.
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