Read Derailleur has snapped off

For discussions about bikes and equipment.
Cyclist436!
Posts: 4
Joined: 20 Jul 2022, 2:44pm

Read Derailleur has snapped off

Post by Cyclist436! »

Hello,

So i was cleaning my bike today and the rear derailleur just came of in my hand, wasn't much force required. The metal has just sheared of which looks like metal fatigue which doesn't surprise me considering how many miles i've done on it over the last 3 years or so.

I guess i'm lucky it didn't snap of when i was moving at speed so there is that.

So a few questions then.

Am i safe to glue it back together. Nothing fell of the bike its just a clean break of the metal.

If not then can i order parts online and fix it myself and if so what parts would i need to order.

The bike is a boardman roadbike SLR 8.9
Attachments
298533657_774781730378638_510674196067053262_n.jpg
PH
Posts: 13099
Joined: 21 Jan 2007, 12:31am
Location: Derby
Contact:

Re: Read Derailleur has snapped off

Post by PH »

Looks like the derailleur hanger has snapped, these are sacrificial parts, deliberately intended to be the weak point to protect damage to frame or mech, though they shouldn't just break...
I doubt there's a glue that would hold, the part isn't expensive and being a Boardman is probably easily available, though there are that many variations care is needed to get the right one.
cycle tramp
Posts: 3479
Joined: 5 Aug 2009, 7:22pm

Re: Read Derailleur has snapped off

Post by cycle tramp »

Blimey! ... this post has now been edited, following PH's post below
Last edited by cycle tramp on 13 Aug 2022, 4:04pm, edited 2 times in total.
It's time to go :-)
cycle tramp
Posts: 3479
Joined: 5 Aug 2009, 7:22pm

Re: Read Derailleur has snapped off

Post by cycle tramp »

PH wrote: 13 Aug 2022, 3:53pm Looks like the derailleur hanger has snapped, these are sacrificial parts, deliberately intended to be the weak point to protect damage to frame or mech, though they shouldn't just break...
I doubt there's a glue that would hold, the part isn't expensive and being a Boardman is probably easily available, though there are that many variations care is needed to get the right one.
I think in this instance the hanger is or rather was part of the frame - certainly I am unable to see any evidence (bolt, indent or line) which would lead me to conclude that the derailleur hanger was a separate piece from the frame. Perhaps if we could have another photo without the wheel in place.
It's time to go :-)
PH
Posts: 13099
Joined: 21 Jan 2007, 12:31am
Location: Derby
Contact:

Re: Read Derailleur has snapped off

Post by PH »

cycle tramp wrote: 13 Aug 2022, 3:59pm
PH wrote: 13 Aug 2022, 3:53pm Looks like the derailleur hanger has snapped,
I think in this instance the hanger is or rather was part of the frame
I think one of us needs to go to Specsavers! it looks like a separate part to me.
cycle tramp
Posts: 3479
Joined: 5 Aug 2009, 7:22pm

Re: Read Derailleur has snapped off

Post by cycle tramp »

PH wrote: 13 Aug 2022, 4:04pm
cycle tramp wrote: 13 Aug 2022, 3:59pm
PH wrote: 13 Aug 2022, 3:53pm Looks like the derailleur hanger has snapped,
I think in this instance the hanger is or rather was part of the frame
I think one of us needs to go to Specsavers! it looks like a separate part to me.
Yes you're right. I shall book my appointment immediately! Apologies i'm so use to seeing breakaway derailleur hangers bolted to the frame - that I thought this hanger was actually part of the frame. It's now with careful looking I can see it's not.
Well, I am very glad to be wrong! :-D
Firstly on the account of the poster who can now pick up a new hanger without to much faff or money and secondly because I've learnt something new - that breakaway derailleur hangers can look neat and understated
It's time to go :-)
Cyclist436!
Posts: 4
Joined: 20 Jul 2022, 2:44pm

Re: Read Derailleur has snapped off

Post by Cyclist436! »

I got the bike brand new on a cycle to work scheme from halfords in 2018. i barely touched it until 2019 when i started using it bit more, then when the pandemic started it became an addiction, i reckon i've cycled roughly 13500 miles on it since 2019 so its been well ridden :D

It's only been in the bike shop once and that was about 4 months ago. i got the cassettes changed as well as a few other parts. The guy told me that the part he was gonna replace was slightly the wrong size but the only difference i would notice would be i would lose some speed in a high gear. It was either that or wait weeks to get the right bit. Naively i said yes.

About 3 days later the gears started playing up and the chain kept contantly falling off. I took it back in and he said he would sort it but it's never been the same since. Could be a complete coincidence this has happened now who knows.

I've took the wheel off and added another pic. Maybe a small video would be better if the pic isn't clear enough?

So what part would i need to order? My bike knowledge is limited but i'm a fast learner and i'm very keen to get back in the saddle.
Attachments
298437821_855847518716200_5148332442416358434_n.jpg
Valbrona
Posts: 2687
Joined: 7 Feb 2011, 4:49pm

Re: Read Derailleur has snapped off

Post by Valbrona »

Derailleur hanger for a Boardman SLR 8.9.
I should coco.
Mike Sales
Posts: 7860
Joined: 7 Mar 2009, 3:31pm

Re: Read Derailleur has snapped off

Post by Mike Sales »

Sorry. Wrong thread.
Attachments
rishi swimming pool.jpg
It's the same the whole world over
It's the poor what gets the blame
It's the rich what gets the pleasure
Isn't it a blooming shame?
User avatar
Sum
Posts: 323
Joined: 17 Jul 2010, 9:13am

Re: Read Derailleur has snapped off

Post by Sum »

You willl need a rear mech hanger, plus some suitable tools (Allen keys) to remove the bolts that I assume are holding what's left of the old rear mech hanger to the frame and also the rear mech.

You can sometimes order them from the internet. Sometimes just the make and model and year of the bike is sufficient but don't order a mech hanger just by looking at the picture. Sometimes there are several that look very similar but aren't interchangeable. It's best to identify the mech hanger by seeing if there's a number or code written on it. Here's a couple I've found by googling:-
https://www.gear-hanger.co.uk/info/boar ... anger/927/
https://www.gear-hanger.co.uk/info/boar ... anger/939/

NB These are probably the wrong mech hangers, but they serve to give you an idea of what to look for in terms of identifying marks on the mech hanger.

Mech hangers are prone to getting knocked and on some bikes they are sacrificial, replaceable parts. The poor gear changing you experienced may have been because the mech got knocked out of alignment and maybe the hanger was bent back in the shop which then weakened it. However, when you replace the hanger, check the gears work ok and that there's nothing that can cause the mech or chain to catch on something and rip the hanger off. Best do this by moving the pedals by hand first.
rjb
Posts: 7183
Joined: 11 Jan 2007, 10:25am
Location: Somerset (originally 60/70's Plymouth)

Re: Read Derailleur has snapped off

Post by rjb »

Your photos are not entirely clear but it looks as if the hanger fitted has been bodged. It should have been bolted between the frame and the wheel so the wheel would offer additional support. Your photos look like it has been bolted inside the drop out so may not be the correct item and the mechanic has fudged it to get you back on the road. could explain why it failed.
If I'm wrong I'm going to Specsavers too. :wink:
At the last count:- Peugeot 531 pro, Dawes Discovery Tandem, Dawes Kingpin X3, Raleigh 20 stowaway, 1965 Moulton deluxe, Falcon K2 MTB dropped bar tourer, Rudge Bi frame folder, Longstaff trike conversion on a Giant XTC 840 :D
PH
Posts: 13099
Joined: 21 Jan 2007, 12:31am
Location: Derby
Contact:

Re: Read Derailleur has snapped off

Post by PH »

rjb wrote: 13 Aug 2022, 6:08pm Your photos are not entirely clear but it looks as if the hanger fitted has been bodged.
Looks fine to me. I've only had two bikes that used them and they've both been recessed on the outside of the frame.
User avatar
Paulatic
Posts: 7796
Joined: 2 Feb 2014, 1:03pm
Location: 24 Hours from Lands End

Re: Read Derailleur has snapped off

Post by Paulatic »

Are there stiff links in that chain? Worth checking as It’s looks to be hanging strangely.
Whatever I am, wherever I am, this is me. This is my life

https://stcleve.wordpress.com/category/lejog/
E2E info
peetee
Posts: 4287
Joined: 4 May 2010, 10:20pm
Location: Upon a lumpy, scarred granite massif.

Re: Read Derailleur has snapped off

Post by peetee »

The business of replacement has been adequately covered by previous posts but just to make it perfectly clear to any third parties reading this in future I will add the following;
Gluing the old part is not an option. No glue yet devised is strong enough to do the job.
Ithankewe. 8)
The older I get the more I’m inclined to act my shoe size, not my age.
User avatar
foxyrider
Posts: 6042
Joined: 29 Aug 2011, 10:25am
Location: Sheffield, South Yorkshire

Re: Read Derailleur has snapped off

Post by foxyrider »

PH wrote: 13 Aug 2022, 6:23pm
rjb wrote: 13 Aug 2022, 6:08pm Your photos are not entirely clear but it looks as if the hanger fitted has been bodged.
Looks fine to me. I've only had two bikes that used them and they've both been recessed on the outside of the frame.
I have a couple of frames with similar hanger arrangements.

Looking at the pics, the RD has clearly taken quite a few knocks, lots of paint missing, so maybe the mechanic did have a go at straightening the hanger which inadvertently caused the failure. These hangers always need some assistance to break, even a single drop can however bend them at which point they should be replaced, they are not intended to be reset.
Convention? what's that then?
Airnimal Chameleon touring, Orbit Pro hack, Orbit Photon audax, Focus Mares AX tour, Peugeot Carbon sportive, Owen Blower vintage race - all running Tulio's finest!
Post Reply