Incorrect chain routing through rear derailleur, lug sawn half through

Discuss light weight issues concerning road bikes & parts.

Moderator: robbosmans

Post Reply
User avatar
musiclover
Posts: 423
Joined: Mon Sep 30, 2019 11:58 pm

by musiclover

https://photos.app.goo.gl/FXyniXCic7ZQPo1q7

I could say I am an idiot. But in my defence I had to put the chain on half asleep at 0300 hours at night in the dark and then ride in the dark on a noisy road and through a thunderstorm.

Then I realised the chain did not sound right. Because I took it off upon coming home, took me a while to understand what happenned.

Anyway, the damage to the routing log and possibly chain outer links has been done.

Are their any consequences to this lack of technical culture? Does anything need replacement? Anything needs fixing? Has it happenned to anyone else?

Nezz0r
Posts: 28
Joined: Wed Apr 22, 2020 2:26 pm

by Nezz0r

I've done it (also rush job) but noticed it right away. I would replace chain. The lug is not pretty but I'd say still functional; that I think is an optional replacement

Edit: replace chain so I'd feel comfortable. The lug I would clean up with a file and leave as is.

by Weenie


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

www.starbike.com



kode54
Posts: 2673
Joined: Tue May 23, 2006 9:39 pm

by kode54

I've made that mistake as well and didn't realize it until the lube/wax ran thin and started to make noise. Live and learn. You would think that the pin would be replaceable...but I think it is attached to the outer plate with a small bolt, since I have seen a few outer plates with the pin detatched. The pin inbetween the two pulleys are attached to the inner plate...both can be replaced.
- Factor 02 VAM Disc
- Factor LS Disc
- Sturdy Ti Allroad Disc
- Guru Praemio R Disc
- Moots Vamoots Disc RSL Ti
- AX Lightness VIAL evo Rim

Cleaner
Posts: 206
Joined: Wed Oct 28, 2009 7:13 pm

by Cleaner

I would inspect the chain. If it looks good I would just clean it very well to get the metal shavings out of the links and put it back in service.

User avatar
ms6073
Posts: 3773
Joined: Fri Jul 23, 2004 8:24 pm
Location: Houston, Texas

by ms6073

Never done that myself, but I did fix that problem on a bike out on the road after overhearing a young rider asking one of the leaders of his ride group why his bike was so hard to pedal, especially on the uphills about 40-miles in on a 62-mile fund raising ride . :shock:
- Michael
"Solving problems you didn't know you had in ways you probably won't understand"

PoorCyclist
Posts: 488
Joined: Wed Dec 07, 2011 1:26 am
Location: California's country side

by PoorCyclist

I have done it as well but mine was a tab on the SRAM cage on a short test ride. The tab was not holding the 2 halves of the cage together.
So, not structual at least on the SRAM. It was a guide for just incase.
Degreased and put some black paint and cleaned some metal bits but life goes on. Might have shaved 1 gram or so.

There were some shifting issues while doing this (can't shift properly to some gears)

This is just a consequence of not using a workstand to elevate the bike and be able to thread the chain properly, then spin and inspect the bike.

I think that "pin" is aluminum on yours so it wouldn't have wear the chain too much. If it is (pending magnet test) Probably just a cleaning will be good if you don't see any damage on the chain.

I don't know why but I have done it more than once, first time I caught it on the workstand due to noise. But you would think once is enough to be very careful threading the chain.

Nezz0r
Posts: 28
Joined: Wed Apr 22, 2020 2:26 pm

by Nezz0r

ms6073 wrote:
Mon Oct 18, 2021 3:32 pm
Never done that myself, but I did fix that problem on a bike out on the road after overhearing a young rider asking one of the leaders of his ride group why his bike was so hard to pedal, especially on the uphills about 40-miles in on a 62-mile fund raising ride . :shock:
Ooh. Rough.

NiFTY
Posts: 1431
Joined: Sat May 26, 2012 11:26 pm

by NiFTY

Looks like bad wear to the chain links from the photos, i would replace. A snapped chain link at full noise is probably a hospital trip. I would ignore the wear to the bump stop.
Evo 4.9kg SL3 6.64kg Slice RS 8.89kg viewtopic.php?f=10&t=110579" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

by Weenie


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

www.starbike.com



TobinHatesYou
Posts: 8846
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

PoorCyclist wrote:
Mon Oct 18, 2021 4:41 pm
I have done it as well but mine was a tab on the SRAM cage on a short test ride. The tab was not holding the 2 halves of the cage together.
So, not structual at least on the SRAM. It was a guide for just incase.

The lug prevents the cage from pinching. That's really the only thing it's there for so even the amount of damage in the OP's case is fine.

Post Reply