Originally Posted by
anotherbrian
I did 50mi+ of 12%+ repeats on a badly (at least by appearance) cross-chained 11spd drivetrain, and while it never broke, looking down at the chainline as I rode was disturbing.
I don't know the actual % loss to efficiencies, but I'd read the larger idler pulleys were very marginal gains, so would think a straight chainline would have to be beneficial.
....
Leonard Zinn has written a few articles on friction losses, chain line, etc. I am not going to put together a list of articles, but this one article i found rather insightful.
https://www.velonews.com/gear/gear-issue-friction-differences-between-1x-and-2x-drivetrains/
It is easier to see the graph from that article here.
https://www.velonews.com/wp-content/...5%2C871?w=1080
Even with a cross chained drive train on the larger sprockets, the friction losses in watts were not much higher than with the sprockets that had a better chain line.
For my riding on my bikes, when I think about chainline, my primary concern is not friction loss and whether or not it slowed me down, my concern is reduction in chain life.
I have bar end shifters on two touring bikes. One advantage to that is I can tell from the feel of the lever position about where my chain is on the cassette, that makes it much easier to avoid cross chaining than with a brifter where I have no feedback on where I am on the cassette when I shift until I run out of gears on that chainring and need to change the front derailleur. Thus, I am often cross chaining with a brifter for the rear derailleur, but not when using bar end shifters.