ToiletSiphon

The front derailleur on my new Emonda ALR is running reeeeeally close to the crank arm when fully shifted up. How much clearance is actually sufficient to not risk hitting it if I go full gas and flex the frame while pedaling?

noodle soup

1 or 2mm is all you need. If the frame/cranks are flexing, that gap will grow under power.

HTupolev

Depends on your frame and your pedal stroke. A simple test is to try it out. If everything is silent, then your clearance is probably sufficient. But if you hear a tick sound at the top of the pedal stroke, you could consider making a microscopic adjustment to the FD.

rayooo

My Domane w/Ultegra runs very close also... just a few mm.

audiomagnate

I clicked on this thread thinking Shimano was blowing out some excess inventory.

Fendertele

Haha I did the same.

ToiletSiphon

In my case it's about 1.5 to 2mm. Same for you?

noodle soup

that is normal

rayooo

I measured mine this morning... I don't have a feeler gauge so used a piece of paper that just fits between crank arm and derailleur, checking the paper thickness with a caliper shows right around 1mm.

ToiletSiphon

Thanks, much appreciated.
A tip for you: I measure clearance (tires or otherwise) by inserting different sizes Allen key. For my derailleur, the 2mm won't fit but the 1mm is loose, so I'm somewhere in between.

rayooo

Ah, yes, good idea on the Allen key, thanks for the tip!