Help with eTap rear derailleur hitting the spokes (on Canyon CF SLX)

Discuss light weight issues concerning road bikes & parts.
Vtrdaz
Posts: 9
Joined: Sun Sep 18, 2016 4:19 pm

by Vtrdaz

I like that idea , in fact I'll try it myself - I think I have a 1mm spacer lying about somewhere

Darren



dorin wrote:I ordered 2 spacers, the ones coming with the wheel sets are all 1.75mm, I hope 1 mm should work. I can close the lock ring but the 11 cog spins freely, let me try with the 1mm ones, the cost is ridiculously low (2usd)

Thanks for the tip, I'll report once I have it

Cheers, Dorin

PinaRene wrote:TIP :

* What I did with my 11- speed wheels ( Bora One / Mavic CCU / Ultegra 6800 ) is a 1mm spacer ring behind the big cog like normally done on the 10 speed cassettes. Maybe I will let my colleague make some 0.7mm aluminium spacers in the future.

Now they all work well and fit the frame fine. The best thing is that the rear derailleur isn't touching the spokes anymore on the Bora wheels while the chain is off. The only thing you have to take care of, is that the lockring still works fine and has enough thread in the body.

I use a 12-28 cassette on the Bora's and the hardest thing was to get the rear derailleur on the 12. Limit screw is just touching and then it's perfect now.

Image

This is just 1mm in real life between derailleur and spoke 8)

by Weenie


User avatar
PinaRene
Posts: 466
Joined: Mon Feb 12, 2007 12:08 pm

by PinaRene

Vtrdaz wrote:I like that idea , in fact I'll try it myself - I think I have a 1mm spacer lying about somewhere

Darren



dorin wrote:I ordered 2 spacers, the ones coming with the wheel sets are all 1.75mm, I hope 1 mm should work. I can close the lock ring but the 11 cog spins freely, let me try with the 1mm ones, the cost is ridiculously low (2usd)

Thanks for the tip, I'll report once I have it

Cheers, Dorin


And did you try it ?

Vtrdaz
Posts: 9
Joined: Sun Sep 18, 2016 4:19 pm

by Vtrdaz

Not yet - totally forgot about it , but I have some spare time this week to give it a go

dorin
Posts: 68
Joined: Mon Dec 19, 2016 3:21 pm

by dorin

sorry, in holidays, will try in 2 weeks or so, i did get the spacers just on 10th...

Vtrdaz
Posts: 9
Joined: Sun Sep 18, 2016 4:19 pm

by Vtrdaz

I've managed to get a .8mm spacer i'm going to fit tomorrow - i'll let you know how i get on!

Darren

Vtrdaz
Posts: 9
Joined: Sun Sep 18, 2016 4:19 pm

by Vtrdaz

OK ,
I fitted the .8mm spacer this morning and refitted the wheel - for me this did not work - with the extra spacer fitted , the slight dome shape of the locking was just touching the frame causing the wheel to bind a little as it span.
So i've gone back to how it originally was and fitted a sram chain catcher for a spot of added insurance.

Darren

strayduck
Posts: 15
Joined: Mon Apr 23, 2012 7:27 pm
Location: New York, NY

by strayduck

Given the range of frames and wheels described in this thread it's sounds like there are very few configurations out there in the wild that could even be considered 'compatible'. Sorry, but I'm 100% with those who think this deraileur-in-the-spoke situation is a horrible, horrible liability.

So we need to come up with some solutions for those who don't have one of these mythical compatible solutions as it looks like SRAM has no interest.

Solution #1 seems to be to buy a SRAM chain catcher which theoretically solves for the more common scenario of the dropped chain. It will keep the chain from falling off the inner chainring on the front, presumably keeping just enough tension on the chain to prevent the rear deraileur from jamming into the spokes.

Now for the mad scientist stuff:

Potential Solution: @sugarkane mentioned something in the linked thread about "SRAM mechs don't use a sprung pivot like campag and shimano". Does anyone know if such a spring can be swapped in?

Potential Solution: You know how Canondale has their "lefty" fork where the front wheel is held on by only one fork leg? Could a similar strategy be employed in which the bottom pulley jockey is held on by only the outer bolt, freeing up multiple mm on the inside where the arm would otherwise rub? If the remaining arm were stiff enough I don't see any reason why this would have to hurt shifting performance.

Or perhaps the cage could be left mostly intact, but the inner bottom portion below the axle area could be removed. If the chain breaks that safety ridge isn't going to keep the chain attached to the bike so it's mostly useless.


I've attached photos of my rather unfortunate spoke-hitting scenario: Merlin Works CR, Mavic Cosmic SLR with carbon spokes, Shimano 11sp cassette on Shimano 10/11sp freewheel body. My bike is currently sitting in the shop and they've swapped our deraileurs, wheels and put washers on the dropout and on the inner of the freewheel body. They have also swapped in a SRAM cassette. Nothing is getting that deraileur off the spokes as it stands!

Image

Image

stien
Posts: 17
Joined: Sat Apr 12, 2014 12:09 pm

by stien

Edit: I see you've tried the washer inside the drive-side hub. I'm surprised that didn't work. I wonder if a trispoke or disc rear would have the same issue.

strayduck
Posts: 15
Joined: Mon Apr 23, 2012 7:27 pm
Location: New York, NY

by strayduck

Update time with bad news and good news.

The bad news is that I don't have a solution for a Canyon CF SLX. The good news is that I have a solution for the Merlin Works CR/Mavic Cosmic SLS (and possibly older mavic wheels more generically). It looks like everyone is going to end up with their own custom config with your worst case being the possibility of having to switch out your wheels or do something scary to your deraileur.

Before I dive in your experience may vary widely--I've got a buddy who took his Scott Addict with custom bikehubstore.com wheels and milled out the back of his Ultegra cassette and jammed it on a 10sp body, essentially moving everything CLOSER to the hub. Meanwhile on the opposite end I needed to move it AWAY from the hub using a new freehub body described below.

Lastly, Mavic seemed surprisingly unknowledgeable about the issue, despite countless wheels going through the 10sp -> 11sp transition. FWIW they did offer to 're-dish' my wheel if it came to that. I don't know much about the process but given that I've got about 5mm between my 23mm tires and my frame, I'm glad to not need that.

So, for older mavic wheels it all boils down to the freehub body.

Details are scarce and there is a lot of documentation that suggests that you can take a 10sp freehub body, remove the spacers that come with it, slap on a 11sp cassette and you're off and running, but that was definitely not the case for me.

Looking at the OUTSIDE newer 11sp freehub body next to the older 10/11sp freehub body you wonder how on earth the 11sp is going to fix the spacing problem (they are all but identical), but if you look INSIDE the newer 11sp freehub bodies have an extra washer which effectively pushes the entire thing out and away from your hub. This made all the difference:

Image

Could it be that simple?! It appears so:

Image

Just as confirmation, the cassette body is exactly the same size on the outside so that lil 11 tooth cog isn't getting pushed out or anything:

Image

Out of an abundance of caution, and because I didn't believe the freehub body would fix the problem I picked up a SRAM chain catcher. It's like a dream catcher, except for chainrings:

Image

Image

So hopefully that helps some Mavic people. Good luck to everyone else! I'm going to stay subscribed to this thread to see how things continue to shake out.

asiantrick
Posts: 115
Joined: Fri Dec 04, 2015 11:18 pm
Location: the OC, CA

by asiantrick

When you have spent a good chunk of your money to "upgrade" to ETAP, you should not be expected to make any modification for it to work properly. I had so many issues with my Etap regarding this and drop chain, that I ended up giving up and go back to mechanical. Good luck OP, i hope you get all this sorted out.

Samklee15
Posts: 69
Joined: Wed Jun 01, 2016 11:18 pm

by Samklee15

I have 2 bikes built up with eTap and have noticed this issue on both. My solution is to just make sure my chains get swapped before they're heavily worn so there is no chance of it breaking. Presents zero issue when the chain is installed.

dorin
Posts: 68
Joined: Mon Dec 19, 2016 3:21 pm

by dorin

I am overdue with an update here! I tried the 1mm spacer and worked great, hopefully will. It have to ever be proven right or wrong :)

dorin
Posts: 68
Joined: Mon Dec 19, 2016 3:21 pm

by dorin

Another update: I upgraded to a WifLi derailleur and I had the same issue, problem solved with the spacer and kept a higher distance on the B-adj screw as if I was leaving it 4-6mm as said in manual, when there is no chain attached the jokey wheel hits the biggest cog. Had a mountain pass ride, all went flawlessly and having a 11-32 is awoesome.

Maybe some manufacturers have different distances on their RD hangers as having the same issue with WifLi rules out defective RD.

The spacer solution worked for me.

Cheers,
Dorin

robindien
Posts: 1
Joined: Wed Jan 17, 2018 3:14 pm

by robindien

Hey everyone,

eventhough this topic was quite for some while, I was recently facing the exact same issue, when upgrading my Ultegra mech to an ETAP set-up on my ROSE XEON RS 3000) and I found reading through your answer very helpful - so here is my stroy about it.

When I tried to install the rear derailleur (without a chain on) it was hitting the spokes in a way that it would have destroyed pretty much everything when it happens during riding. I hereupon contacted the SRAMTECHCENTER in UK - below their answer:

Hi Robin,

I have looked at the photos you have sent over, and this derailleur is completely normal, there is no fault with it.
In some instances, with certain wheels, the derailleur can sit close to, or make contact with the spokes when there is no chain fitted, however once the chain is fitted this will not cause any issues.

Kind regards,
Will


Obviously the answer is inadequate and I tried to call the guys to discuss especially the fact of "WHAT IF". However, they were reluctant to admit its a design flaw and mentioned multiple times how rare the chances of such failure are. They also said they saw the same issue with the small cage - there is no solution from SRAM to this issue. I am more than disappointed with that situation especially considering the money I spent on this groupset.

I then tried to figure out how to modify the set-up to at least be safe in case of a failure.
Haven't had a spacer at hand to put behind the cassette but I figured out that you gain a few millimeter (distance) with a wolf tooth road link derailleur hanger extension. Just enough that the cage would touch the spokes, maybe even be dragged with the rotation but once hitting the cog snap back down.
I furthermore installed a chain catcher, which will hopefully hold up the chain tension just enough so the rear mech does not get trapped or dragged by the spokes.

I agree that the likelihood might be little, but still think that type of product and at the cost it comes with, this should not happen!

happy to hear if someone else in the meantime either found another solution or had different issues...

Cheers
Robin

dorin
Posts: 68
Joined: Mon Dec 19, 2016 3:21 pm

by dorin

Hi Robin, I did as you, install a chain catcher as that would be the only time I see a chain failing may let the deraileur lose and hit the spokes. In the end I concluded the amount of time I spent trying to solve this highly unlikely event of a chain braking is not worth it, that’s when the insurance will kick in.

From safety point of view i’m Ok, I doubt I’ll ever reach 30km/h up hill for the deraileur to destroy the rear wheel and cause me to crash and injure :)

1mm spacer does the job though ;)

by Weenie


Post Reply
  • Similar Topics
    Replies
    Views
    Last post