Originally Posted by
SlinkyWizard
Thanks for the graph,
when in the small chain ring, my sweet spot is on the 13T , but I noticed the chain is rubbing on the front derailleur, thus making a sound, so I go to the easier 14T , and no sound,
when in the big chain ring, my sweet spot is on the 20T, but there is sound, so I go to the harder 18T, and the sound stops.
Will adjusting the front derailleur let me get into my sweet spot with no noise?
Shimano 105 11 speed drive train, Front derailleur is Shimano FD 5801
Trim
The
front shifter has a "trim" position, to move the derailleur cage slightly without shifting. It's for stopping the derailleur cage from a slight rubbing in some gear combinations. Do you use this?
Derailleur adjustments / tuning
The front derailleur needs to be adjusted correctly for smooth shifting and to keep from dropping the chain during a shift. The cage height above the big chainring, the angle of the cage edge along the chainring, and the cable tension are all critical.
Shimano has "dealer manuals" online. These are good if you want to do your own maintenance. They are detailed, step-by-step installation and adjustment procedures.
Here's the 105 front derailleur (also applies to other Shimano 11-speed models)
http://si.shimano.com/pdfs/dm/DM-RAFD001-02-ENG.pdf
Here's a video that may help:
Art's Cyclery Blog » Ask a Mechanic: Shimano Front Derailleur Trim Set-Up and Adjustment
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The manual has a confusing page about cross chaining in the small chainring:
indicating that the smallest 3 cogs might have noise. I thought it was usually just the two smallest cogs, not the third.
But they say "shift the chain to the second largest" ?? That makes no sense.