Sram eTap rear derailleur sporadically stops shifting - then performs all queued shifts at once?

Back by popular demand, the general all-things Road forum!

Moderator: robbosmans

bobones
Posts: 1271
Joined: Mon Aug 12, 2013 11:19 am

by bobones

A bit too far, sorry.

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

www.starbike.com



purplecu22
Posts: 10
Joined: Sun Dec 05, 2021 12:01 pm

by purplecu22

So i have been given 2 bad red 11 speed. wifi. deraileurs.

Ive followed this post.

Can you do a from bad to finish post?

Circuitin
Posts: 6
Joined: Fri Dec 06, 2019 3:03 am

by Circuitin

Monsterinyourhead wrote:Thanks to this thread, I was able to get a WiFli RD in what appears to be working order. It will complete a full range of shifts but, I am to a point where I am uncertain if it will behave correctly when under load. Let me explain...

I followed the steps shown in this thread on how to get into the gearbox of the derailleur. Once I was able to open the two halves, I noticed the oring gasket that spans the perimeter wasn't seated properly. With that said, I observed a fair amount of grime and debris in this area of the housing. This is just a wild assumption but, I suspect maybe this resulted in moisture and or corrosion on the PCB of the derailleur. I acquired this derailleur for a fair price and I wasn't concerned about damaging it any further. I used 99% isopropyl alcohol and a toothbrush to lightly scrub both sides of the PCB. Since I gave the board a nice scrub, I thought I would also clean and regrease all of the gears. It wasn't until I removed all of the gears that I realized I may have a problem.

I marked the position of the arm that was affixed to the gear shaft but, by removing all of the gears I think I upset the timing of the system. I say this because, once I removed the gears, I noticed once of them was magnetic and the other one was spring loaded. See attached picture. The gear that is spring loaded, I left in the housing. With that said, the magnetic gear indicates the system uses a Hall Effect Sensor.....to which I know nothing about.

My main question/concern relates to that gear shown in my picture that is spring loaded. This gear and the magnetic gear must not carry any load because; only the lower axle on each gear is secured. I don't know if the Hall Effect sensor controls the shifting limits to tell the system not to over shift or if it's a safety feature....or both?

I'm really wondering what position the spring loaded gear should be in upon reassembly? Does it need to be preloaded? I reached out to Sram but, I am guessing they won't offer this kind of technical support :)
how did you remove the two fat pins? after 1 hour I was unable


Enviado desde mi iPhone utilizando Tapatalk

User avatar
LiKuid
Posts: 73
Joined: Thu Oct 24, 2013 1:09 pm

by LiKuid

Circuitin wrote:
Thu Aug 11, 2022 8:23 am
how did you remove the two fat pins? after 1 hour I was unable
Me too.. Got 2 etap derailleurs that dont work and i cannot get the 2 pins to move at all.
Anybody got a hack on that? I hammered them with a plastic hammer pretty hard. But they didnt even seem to bother...
I am afraid that i am gonna destroy the derailleur body if i keep insistingn :noidea:

jamiejmuk
Posts: 3
Joined: Sun Mar 13, 2016 1:48 pm

by jamiejmuk

I can't get the pins out. I've tried a hammer+pin punch and pressing with with adjustable pliers.
Does anyone have any other suggestions?

It seems like it is the head end of the pins that are stuck, has anyone tried grinding the heads off and drilling through the pins? Is there anywhere that sells replacement pins?

User avatar
LiKuid
Posts: 73
Joined: Thu Oct 24, 2013 1:09 pm

by LiKuid

After i broke my first derailleur, I took the 2nd to a machine shop and they spent some time and effort to split it. They finally did and I ve been looking at it since. I am not sure what kind of oil or degreaser is safe to use to clean it. More importantly, I dont think i stand any chance of putting it back together. That is above my talent as an amateur with home garage tools.
All in all it takes a lot of skill to get the derailleur back working. If you insist in trying, I suggest you visit a machine shop and then consult a guy with a background in servicing electronic parts so that you dont mess up.

jamiejmuk
Posts: 3
Joined: Sun Mar 13, 2016 1:48 pm

by jamiejmuk

I have a "broken" medium cage, that is exhibitng the "sticky" signs described in this thread, and a good short cage. My hope was to transplant the hanger/battery end of the medium cage onto the electronic/control/sprocket half of the short cage, thus giving a working medium cage hopefully without the need to disassble the electronics control box.

I had not imagined that just getting the parallelgram pins out would be so difficult.

gizgaz
Posts: 13
Joined: Sat Jun 13, 2015 11:52 am

by gizgaz

Don't know if anyone has mentioned this in the thread so far but I was having a similar issue of RD not shifting some times outbound.
For me the problem seemed to be a pairing conflict between my garmin 830, garmin tactic delta watch (similar to fenix 7x). I removed the etap from sensors on both and it's solved the issue. 🤯
I think the garmin watch and head unit were having an argument over which was paired with the etap. Each time they were arguing the RD would miss shifts.
So weird.

UPDATE: This didn't work. Back to my itermittent outward shift failures.

Post Reply