Help: SRAM Red Axs Front Derailleur Shifting

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CHL
Posts: 18
Joined: Sat Aug 09, 2008 11:20 pm

by CHL

Hello:

Trying to migrate from Etap to Axs with a great difficulty. Cannot get the front derailleur to shift into the large chainring. Using a Rotor Aldhu (24mm spindle) crankset with 50/37 Rotor AXS chainrings. The small chainring is correctly oriented (doubled check already on this) . With the alignment marks of the cage (front & rear) matching the large chainring, the crank arm strikes the rear end of the cage as it rotates. It shifts okay. If I rotate the cage just a smidge outward, it shifts properly.

If I rotate the derailleur inward even with 1mm of clearance between the crank arm and the outer plate of the cage, the derailleur will not shift the chain into the large chainring. Also, the front derailleur over-shifts to move the chain onto the large chainring. While it is over shifted, the crank arm will striker the outer plate of the derailleur again. I've adjusted the height, brought the inner cage even touching the chain (small/small combo) to no avail. Is anyone running SRAM AXS with a Rotor crankset? I'm using a Xcadey Power Meter but I reinstalled the Rotor spider, the problem remains. I am using a SRAM force chain. The chain is correctly sized.

Is the SRAM drivetrain only compatible with a SRAM crankset and chainring? My 11 Speed Etap shifts w/o hesitation and near Shimanoish performance... Appreciate any insight. Thank you.

C.
PS. If anyone is running a SRAM crankset, would you have the distance between the crank arm and the large chainring so I can compare with Rotor crank setup?

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wheelsONfire
Posts: 6283
Joined: Mon Jul 07, 2014 8:15 am
Location: NorthEU

by wheelsONfire

Sounds like a pain in the ass. I actually heard just a few days ago that 1 gen Etap works better with Rotor than the later AXS does.
I guess you use the short/ regular axle?
I didn't expect the Rotor crankarms to have this issue with FD cage clearance to crankarm. My FSA K-Force have way better clearance compared to my Sram Red crank and even shift better.
Hearing what you say + the fact that a dealer hinted at this, makes me rethink the idea of Rotor as an option.
If i bought a Rotor crank i would do so with the idea it should work with 12 speed to.
I'm not even sure Eastons EC90 crank has a good clearance.
A pity new FSA K-Force team edition is so expensive. I think this might be a really good crankset.
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Ax Lightness Vial EVO Race (2019.01.03)
Open *UP* (2016.04.14)
Paduano Racing Fidia (kind of shelved)


Ex bike; Vial EVO D, Vial EVO Ultra, Scott Foil, Paduano ti bike.

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rollinslow
Posts: 864
Joined: Fri Dec 21, 2018 2:25 am
Location: New York

by rollinslow

I would double check the spindle (43.5mm vs offset one), check your spacers if any, check the limits again, check cage angle again. There's no reason it should not work.
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