Sram etap FD chain drops

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jlok
Posts: 2400
Joined: Tue Jun 30, 2015 3:30 am

by jlok

Sorry but I didn’t know I was replying to you at the beginning... so threes is your alias?

p.s. ok I give up. i will just save your post and let everyone refer to it as your method is comprehensive and can solve issue.
Rikulau V9 DB Custom < BMC TM02 < Litespeed T1sl Disc < Giant Propel Advanced SL Disc 1 < Propel Adv < TCR Adv SL Disc < KTM Revelator Sky < CAAD 12 Disc < Domane S Disc < Alize < CAAD 10

morganb
Posts: 732
Joined: Wed Mar 15, 2017 5:30 pm

by morganb

Mine has a strange shifting issue, I can't get it to shift small to big under light load, but it shifts fine under heavy pedaling, even attacking out of the saddle up a climb. I wonder if it's the less than aggressive profiling on my chain rings (Rotor NoQ)

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RedbullFiXX
Posts: 234
Joined: Sat Aug 05, 2017 6:13 am

by RedbullFiXX

Canyon Ulimate SLX with Etap HRD here
As delivered, dropped off small and big rings
Fine tuning adjusted, been perfect for thousands of miles now
Charge batteries on the first of the month, easy :)
Cyclocross, in general, is about riding the wrong bike for the conditions.

threes
Posts: 3
Joined: Wed Jun 06, 2018 5:15 pm

by threes

Got my Synapse back after ETAP has been tweaked again. This time the workshop notes say:

- Chain shortened by 1 link
- RD B tension adjusted to be within 4-6mm

Had a couple of rides and so far no further issues with the chain dropping when chainging the FD :)

BdaGhisallo
Posts: 3261
Joined: Wed Mar 17, 2004 1:38 pm

by BdaGhisallo

TobinHatesYou wrote:
Wed Jun 06, 2018 9:47 pm
With compact chainrings, the adjustment that has made the biggest difference for me is using the top hole of the angled shim that SRAM sells. Second biggest improvement was using certain chains like the KMC X11SL.

https://www.artscyclery.com/SRAM_Braze- ... RFDSH.html
So one of the keys to getting SRAM's top drivetrain components to work properly is to use a chain that they don't make and probably won't recommend? Interesting.

bcmf
Posts: 129
Joined: Fri May 22, 2009 5:00 pm

by bcmf

Was experiencing drops on both inside and outside with non sram rings with both compact and standard chainsets.
Bike is Ridley Noah FAST! with a braze on tab.
Found that to align the marks on the cage with the large chainring was putting the fd at its absoloute limit on the braze on. Add the bracing tab was actually throwing the alignment off partly I am guessing to the shape of the seatpost.
Had to carefully insert the tab so it was barley touching the seatube.
Then had to set the marks up as close as possible then make tiny movements on the tail to get it to clear the crankarm as it came up.
Then I had to start making tiny adjustments on the outer limit screw and by tiny I mean just moving the limit by a tiny turn until it wouldnt overshift.
For the inner ring I found that running the inner cage very very close to the chain on the easiest gear ( and am prepared to accept some slight rubbing),
I am putting the issues down to the shape of the seatube and angle of the braze on tab.
Since I spent time figuring it out I havent had a chain drop either way

With regards to the chain:
I used a Sram chain on the compact and a KMC on the standard.
Made no differnce except that the KMC seems to be noiser at either end of the Sram cassette.
May change it to a Red chain to see if it clears but its not a dealbreaker!

threes
Posts: 3
Joined: Wed Jun 06, 2018 5:15 pm

by threes

threes wrote:
Fri Jun 15, 2018 10:24 am
Got my Synapse back after ETAP has been tweaked again. This time the workshop notes say:

- Chain shortened by 1 link
- RD B tension adjusted to be within 4-6mm

Had a couple of rides and so far no further issues with the chain dropping when chainging the FD :)
This didn't fix it :cry: Chain is still dropping. Now working with LBS to find an alternative solution ...

TobinHatesYou
Posts: 12458
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

threes wrote:
Tue Jun 19, 2018 9:52 am

This didn't fix it :cry: Chain is still dropping. Now working with LBS to find an alternative solution ...
Not sure why a shop wrench would have though b-tension on the RD would fix front shifting. It makes me doubt their competence in correctly setting up the yaw and height of the FD. If you are absolutely certain the position of the FD is correct, you can try the SRAM angled FD shim for use with compact chainrings.

bcmf
Posts: 129
Joined: Fri May 22, 2009 5:00 pm

by bcmf

As per my post above.
Use the guide marks on the fd as that. A guide.
I found that usng them as a start point then making very fine tune adjustments to the fd.
Set the limit screw for the big so that it wont allow the chain to lift. Then wind the limit screw off by a small turn every time till it lifts and leave it.
Then set it in smallest rear and large front so the chain is barely clearing the mech.
REMEMBER:
The mech overshifts when activated so this is where your chain is being thrown off - the mech doesnt even get a chance to 'return' to its natural position.

Digger90
Posts: 107
Joined: Sun Jun 21, 2015 9:34 pm

by Digger90

I had this issue - albeit only once or twice - when I installed Red eTap. Some very minor adjustment was all that was necessary to get it to shift perfectly.

As others have said, likely best to start again from scratch, following SRAM's derailleur setup guide on YouTube to the letter.

jlok
Posts: 2400
Joined: Tue Jun 30, 2015 3:30 am

by jlok

bcmf wrote:
Wed Jun 20, 2018 5:57 pm
Then set it in smallest rear and large front9 so the chain is barely clearing the mech.
REMEMBER:
The mech overshifts when activated so this is where your chain is being thrown off - the mech doesnt even get a chance to 'return' to its natural position.
Solved my issue with the same thinking.
Rikulau V9 DB Custom < BMC TM02 < Litespeed T1sl Disc < Giant Propel Advanced SL Disc 1 < Propel Adv < TCR Adv SL Disc < KTM Revelator Sky < CAAD 12 Disc < Domane S Disc < Alize < CAAD 10

Wormiez
Posts: 63
Joined: Sat Oct 01, 2016 12:46 am

by Wormiez

bcmf wrote:
Wed Jun 20, 2018 5:57 pm
As per my post above.
Use the guide marks on the fd as that. A guide.
I found that usng them as a start point then making very fine tune adjustments to the fd.
Set the limit screw for the big so that it wont allow the chain to lift. Then wind the limit screw off by a small turn every time till it lifts and leave it.
Then set it in smallest rear and large front so the chain is barely clearing the mech.
REMEMBER:
The mech overshifts when activated so this is where your chain is being thrown off - the mech doesnt even get a chance to 'return' to its natural position.
Would you be able to take a picture of this?

I'm having issues with the chain dropping over the chainset.

Wormiez
Posts: 63
Joined: Sat Oct 01, 2016 12:46 am

by Wormiez

Anyone running their Etap with a CS Oversized Pulley Wheel Systems?

Would this cause the chain drop?

I ask this because I notice when going from small ring to the big ring, the chain bounces a bit. This is when it is in moderate load.

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

by wheelsONfire

This seem like a bad joke...
Using the Rotor shim as a solution, make me wonder if the FD is working better at a certain seatmast tube angle (FD angle)?
Using the latest Shimano FD's, you can go for option on chainrings (53/39, 52/36 aso) aswell as the tuning steps.
I can see no clear solution to the problem with ETap FD, as it appears there are several ideas.
Some work in some cases, but not for others!?
I guess gen 2 of Sram Etap should be about getting the FD to work, more so than getting more gears in the cassette.
Bikes:

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.

bcmf
Posts: 129
Joined: Fri May 22, 2009 5:00 pm

by bcmf

Just to update this.
I came back from a 5 week break from the bike and went out for a spin.
First few front changes were perfect.
Then it throw the chain over the outside.
When I got home I threw it on the stand and noticed that the high limit screw had wound out and the outer cage was just about hitting thr crankarm.
Reset it and got it perfect again.
After a couple of hours riding I checked the high limit screw and had definitley wound out again.
Maybe worth checking for those who are having intermittent problems with it!

by Weenie


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