SRAM Red eTap FD chain drop

Discuss light weight issues concerning road bikes & parts.
DaMaDo
Posts: 14
Joined: Thu Jan 31, 2019 1:42 am

by DaMaDo

alcatraz wrote:
Fri Feb 15, 2019 7:20 am
DaMaDo wrote:
Fri Feb 15, 2019 3:07 am
If the shop can't get my etap FD to work well, I'll contact bikecloset and see if they will take it back then switch to DA 9150/9170 setup.

If they won't take it back, I'll get a dual chain catcher
Are you putting load on your crank when you get it to drop the chain? I suggest not to do that, and set the max limit a _tiny_ bit closer every time it happens. With tiny I mean like 2-3/60th of a turn.

How many teeth difference is there between your small and big chainring?

How big a guy are you?

Have you inspected the fd braze on tab and chainrings for play/flex? Just being new and that an lbs installed it is not a guarantee that everything is in order.

Sram does on average not have the same front shift quality as shimano. If you come from shimano you might be used to more force on the pedals while upshifting.

One of my larger friends rides only shimano ultegra/duraace and is complaining about increasing amount of chaindrops. And there is nothing wrong with his setup. After much tweaking it boils down to this. He has gotten used to shifting under load ever since he got into cycling. He hasn't dropped chains very much because he wasn't as strong as he is today. He has broken several chains and is able to eject the chain off the chainring without shifting. He has bent chainrings so the teeth point sideways. The solution (kind of) was to learn how to shift and improve pedaling technique. Up the cadence and this kind of stuff. Even out the power stoke. If this guy decides to break a chain he could at any moment but following good practices allows him to ride reliably, fast and safely.

I'm just hoping that his training program never suggests low cadence sprinting or something because that'll be a lot of work for his mechanic.
I'm actually coming from mountain biking with 1x so this is really my first time shifting with an FD. I guess I didn't know what to expect. I thought stuff just worked.

The load I'm talking about that makes the chain fall onto the cranks is just shifting while steady pedaling on a flat street, no climb or sprint. Works perfect on the stand with no load.

I'm 170 lbs/77 kg.

If SRAM FDs are just like this and I just need to adapt, (well I guess I wish I had gone with Shimano) I will adapt as needed.

Maybe that dual chain catcher will help but I should probably buy some surface protection for the crank arms anyway.

by Weenie


Seedster
Posts: 507
Joined: Fri Jun 05, 2015 11:05 pm

by Seedster

Watched an eTap AXS bike throw a chain a few times tonight during the assembly of a new systemsix aero bike. The mechanics weren't surprised about it in the least. kind of disappointing that SRAM has not addressed the issue in a meaningful way. My impression is they are hoping everyone goes 1x so they can avoid investing in a fix altogether.

alcatraz
Posts: 1922
Joined: Mon Aug 29, 2016 11:19 am

by alcatraz

DaMaDo wrote:
Sat Feb 16, 2019 12:05 am
I'm actually coming from mountain biking with 1x so this is really my first time shifting with an FD. I guess I didn't know what to expect. I thought stuff just worked.

The load I'm talking about that makes the chain fall onto the cranks is just shifting while steady pedaling on a flat street, no climb or sprint. Works perfect on the stand with no load.

I'm 170 lbs/77 kg.

If SRAM FDs are just like this and I just need to adapt, (well I guess I wish I had gone with Shimano) I will adapt as needed.

Maybe that dual chain catcher will help but I should probably buy some surface protection for the crank arms anyway.
Maybe try the hi limit screw method I mentioned.

Check that all bolts are tight. The chainrings or derailleur cage should not noticeably flex sideways.

Nefarious86
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by Nefarious86

Just put Ui2 on it and live happy lol
Using Tapatalk

bcmf
Posts: 79
Joined: Fri May 22, 2009 5:00 pm

by bcmf

I am gonna pitch in here ....again.

I ,just last week, put my etap on my ridley noah sl.
I left my record compact cranks on.
Have about 130 km on it and apart from a quick realingment of the height to stop rubbing in the 50 front and the 3 biggest cogs the shifting has been flawless.
I have deliberatley went through all gear combo and shifting scenario's trying to drop the chain on the outside.
I couldnt.
From last year's experience ( see my previous post's) I made sure that when in Big front and small rear I ran the outer cage very very close to the chain so the overshift doesnt throw the chain.
I believe ,maybe wrongly, that the auto overshift when going from small to big is the culprit and you must keep this to a minimum by using the limit screws.

Also made sure that the marks on the top of the mech for the chainring is as in line as possible.

TobinHatesYou
Posts: 3318
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

Bcmf, you are basically correct, but in my situation I had to run my high limit close enough to actually rub the chain. After a while this led to laggy or even missed front upshifts during the overshift. If the chain failed to get picked up by the big ring’s ramps during the overshift, then the chain would continue to skip along on the small ring while rubbing against the inner cage since the FD was technically in the outer position.

At that point I moved the high limit back out until the laggy shifts went away and oddly I wasn’t throwing the chain during upshifts anymore. I think one of the issues we haven’t talked much about is brand new hardware. The problem is probably amplified with brand new chainrings and chains. Not really a good excuse for SRAM’s poor engineering, but it seems to be one facet of the problem.

Jugi
Posts: 421
Joined: Sun Jun 24, 2018 8:10 am

by Jugi

After about 100 hours of riding almost exclusively on Zwift after installing 1gen eTap on my Tarmac SL6 (56) with Rotor's Q-rings (52/38):
- Two dropped chains to outside, happened on consecutive days
- One dropped chain to inside, most likely user error (severe change in cadence and power while simultaneuosly changing front chainring and multiple cogs at the back)

I have set the limiter screws so they give me some rub at both cross-chained combinations just to have an audible reminder I'm doing something stupid. Front shifting happens effortlessly and fast regardless of chainline. I'd say the front shifting is good, but it's definetly not completely fool-proof.

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wheelsONfire
Posts: 2675
Joined: Mon Jul 07, 2014 8:15 am
Location: NorthEU

by wheelsONfire

If anything, the chaindrops happens when i use trainer/ zwift.
Bikes:

Ax Lightness Vial EVO Race (2018.12.21)
viewtopic.php?f=10&t=156137
Paduano Racing Fidia (kind of shelved)
Open *UP* (2016.04.14)


Ex bike; Vial EVO D

bcmf
Posts: 79
Joined: Fri May 22, 2009 5:00 pm

by bcmf

TobinHatesYou wrote:
Sat Feb 16, 2019 10:33 pm
Bcmf, you are basically correct, but in my situation I had to run my high limit close enough to actually rub the chain. After a while this led to laggy or even missed front upshifts during the overshift. If the chain failed to get picked up by the big ring’s ramps during the overshift, then the chain would continue to skip along on the small ring while rubbing against the inner cage since the FD was technically in the outer position.

At that point I moved the high limit back out until the laggy shifts went away and oddly I wasn’t throwing the chain during upshifts anymore. I think one of the issues we haven’t talked much about is brand new hardware. The problem is probably amplified with brand new chainrings and chains. Not really a good excuse for SRAM’s poor engineering, but it seems to be one facet of the problem.
You maybe onto something there.
It was new chainrings I was having difficulty with.
The rings I am using now have decent wear on them but I put a new chain on after yesterdays spin so will see how that behaves today.

DaMaDo
Posts: 14
Joined: Thu Jan 31, 2019 1:42 am

by DaMaDo

Maybe by the time I get my bike back from the shop (1 month coming up on Friday) they will have tried enough that the chainrings will be worn and working ;)

They called me today because the fully charged batteries I had left with them had been depleted and they needed for me to bring in the charger so they could keep troubleshooting. They said they were going to call SRAM tomorrow.

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wheelbuilder
Posts: 616
Joined: Wed Feb 08, 2017 2:10 am

by wheelbuilder

DaMaDo wrote:
Thu Feb 21, 2019 2:28 am
Maybe by the time I get my bike back from the shop (1 month coming up on Friday) they will have tried enough that the chainrings will be worn and working ;)

They called me today because the fully charged batteries I had left with them had been depleted and they needed for me to bring in the charger so they could keep troubleshooting. They said they were going to call SRAM tomorrow.
They don't have a charger? Could be part of the problem right there if they don't set up a lot of etap.

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wheelsONfire
Posts: 2675
Joined: Mon Jul 07, 2014 8:15 am
Location: NorthEU

by wheelsONfire

I wonder what chainstay lenghts this happens to?
My bike shifts good, if i stop spinning and let the FD shift and let the chain move and settle.
To fast on hitting the spin, it risk to jump.
It seems to be more risk for jump to happen when i ride at Zwift/ trainer.

I have used Etap on a frame with 403mm chainstay length (both frames) and BB drop of both 65 and 70mm.
Seat tube angle, 72.6 and 73.5.
Chainrings 50/36, cassette 11-28.
Cassettes are Shimano DA 9000, UL 6800, Sram XG 1130 and XG 1190. (all 11-28)
My RD is Wifli.
I can use all gears and cross chain (both chainrings) with absoltuelly zero chain rub.
Set up is exactly as described by Sram video clips.
Bikes:

Ax Lightness Vial EVO Race (2018.12.21)
viewtopic.php?f=10&t=156137
Paduano Racing Fidia (kind of shelved)
Open *UP* (2016.04.14)


Ex bike; Vial EVO D

Karvalo
Posts: 547
Joined: Fri Aug 10, 2018 6:40 pm

by Karvalo

DaMaDo wrote:
Thu Feb 21, 2019 2:28 am
Maybe by the time I get my bike back from the shop (1 month coming up on Friday) they will have tried enough that the chainrings will be worn and working ;)

They called me today because the fully charged batteries I had left with them had been depleted and they needed for me to bring in the charger so they could keep troubleshooting. They said they were going to call SRAM tomorrow.
A shop that doesn't have a single eTap battery charger in the building is unlikely to have any experience working wth eTap. Maybe instead of dropping off the charger you collect the bike and take it to someone who does?

DaMaDo
Posts: 14
Joined: Thu Jan 31, 2019 1:42 am

by DaMaDo

wheelbuilder wrote:
Thu Feb 21, 2019 5:41 am
DaMaDo wrote:
Thu Feb 21, 2019 2:28 am
Maybe by the time I get my bike back from the shop (1 month coming up on Friday) they will have tried enough that the chainrings will be worn and working ;)

They called me today because the fully charged batteries I had left with them had been depleted and they needed for me to bring in the charger so they could keep troubleshooting. They said they were going to call SRAM tomorrow.
They don't have a charger? Could be part of the problem right there if they don't set up a lot of etap.
Karvalo wrote:
Thu Feb 21, 2019 11:31 am
DaMaDo wrote:
Thu Feb 21, 2019 2:28 am
Maybe by the time I get my bike back from the shop (1 month coming up on Friday) they will have tried enough that the chainrings will be worn and working ;)

They called me today because the fully charged batteries I had left with them had been depleted and they needed for me to bring in the charger so they could keep troubleshooting. They said they were going to call SRAM tomorrow.
A shop that doesn't have a single eTap battery charger in the building is unlikely to have any experience working wth eTap. Maybe instead of dropping off the charger you collect the bike and take it to someone who does?
Yeah, I'm in a small city. I think I'd have to drive out 2 hours or so to get to a large city like Nashville or Chattanooga that would have a lot more experience. If they can't get it resolved after talking to SRAM, maybe I'll have to do that.

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pdlpsher1
Posts: 2186
Joined: Thu Jul 19, 2012 6:09 pm
Location: CO

by pdlpsher1

I suggest that you get your bike back and call Sram yourself. If the shop has to call Sram then the shop is just an unnecessary middleman.

by Weenie


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