Lost: two gears... Help please adjusting derailleur

General cycling advice ( NOT technical ! )
simonhill
Posts: 3201
Joined: 13 Jan 2007, 11:28am
Location: Essex

Re: Lost: two gears... Help please adjusting derailleur

Postby simonhill » 21 Oct 2020, 3:35pm

I'm confused.

How would the hanger or mech be bent if the bike fell on the other side?

pwa
Posts: 13329
Joined: 2 Oct 2011, 8:55pm

Re: Lost: two gears... Help please adjusting derailleur

Postby pwa » 21 Oct 2020, 3:47pm

I am not sure the mech and the hanger are bent, but it would be surprising if that cable worked correctly. It has a kink in it (probably both the outer casing and the inner cable) and it enters the mech at a very funny angle. That needs swapping for a new cable and new cable housing with nice flowing curves and no sharp angles. I'd fix that first.

pwa
Posts: 13329
Joined: 2 Oct 2011, 8:55pm

Re: Lost: two gears... Help please adjusting derailleur

Postby pwa » 21 Oct 2020, 3:49pm

simonhill wrote:I'm confused.

How would the hanger or mech be bent if the bike fell on the other side?

Maybe it got kicked, or stood on in the confusion.

James Up Hill
Posts: 43
Joined: 7 Oct 2019, 12:39pm

Re: Lost: two gears... Help please adjusting derailleur

Postby James Up Hill » 21 Oct 2020, 4:19pm

10/10 to pwa and roubaixtuesday, thank you both. An entire virtual barrel of beer for you.

I had loosened the cable (as mentioned last week up-thread) so that it was completely floppy slack - but at the handlebar end. By detaching the cable at the derailleur end it showed that - as you correctly observed - nothing was bent and the derailleur mechanism was fine. By straightening the kink in the cable it all seems to be working again. We will find out on the way home!

A two minute job for somebody who knew what they were doing, it's taken me rather longer.

And of course it may have had nothing to do with the accident.

Thank you all so very much indeed. I shall see what happens and may tidy/replace the bits.

roubaixtuesday
Posts: 3448
Joined: 18 Aug 2015, 7:05pm

Re: Lost: two gears... Help please adjusting derailleur

Postby roubaixtuesday » 21 Oct 2020, 4:59pm

James Up Hill wrote:10/10 to pwa and roubaixtuesday, thank you both. An entire virtual barrel of beer for you.

I had loosened the cable (as mentioned last week up-thread) so that it was completely floppy slack - but at the handlebar end. By detaching the cable at the derailleur end it showed that - as you correctly observed - nothing was bent and the derailleur mechanism was fine. By straightening the kink in the cable it all seems to be working again. We will find out on the way home!

A two minute job for somebody who knew what they were doing, it's taken me rather longer.

And of course it may have had nothing to do with the accident.

Thank you all so very much indeed. I shall see what happens and may tidy/replace the bits.


Fab. I would strongly advise replacing both inner and outer cables, and the end caps too.

James Up Hill
Posts: 43
Joined: 7 Oct 2019, 12:39pm

Re: Lost: two gears... Help please adjusting derailleur

Postby James Up Hill » 21 Oct 2020, 5:08pm

Thank you.

Do I just buy a roll of this stuff like this and cut it to fit?

https://www.chainreactioncycles.com/lif ... prod155219

Eyebrox
Posts: 345
Joined: 5 Aug 2015, 8:56pm
Location: Ayrshire

Re: Lost: two gears... Help please adjusting derailleur

Postby Eyebrox » 21 Oct 2020, 6:31pm

Go to a bike shop and they'll cut you an outer and provide the inner. Maybe about £6 or £7.

roubaixtuesday
Posts: 3448
Joined: 18 Aug 2015, 7:05pm

Re: Lost: two gears... Help please adjusting derailleur

Postby roubaixtuesday » 21 Oct 2020, 6:49pm

James Up Hill wrote:Thank you.

Do I just buy a roll of this stuff like this and cut it to fit?

https://www.chainreactioncycles.com/lif ... prod155219


Per previous post, if you pop into a bike shop they'll cut to length for you.

If you do want to buy online, your link is NOT for the right stuff.

You need gear cables. Not brake cables. Both inners and outers are different.

https://www.chainreactioncycles.com/mob ... t=pricelow

pwa
Posts: 13329
Joined: 2 Oct 2011, 8:55pm

Re: Lost: two gears... Help please adjusting derailleur

Postby pwa » 21 Oct 2020, 7:31pm

Eyebrox wrote:Go to a bike shop and they'll cut you an outer and provide the inner. Maybe about £6 or £7.

And if you are not confident about getting it right, pay a bit more and have it fitted.

Brucey
Posts: 41508
Joined: 4 Jan 2012, 6:25pm

Re: Lost: two gears... Help please adjusting derailleur

Postby Brucey » 22 Oct 2020, 12:33am

James Up Hill wrote:...Assuming Brucey is right (quite likely) does this mean a new mech, or can it be bent straight again?


if the mech is bent it isn't by much and it might be in the hanger.

FWIW it is virtually impossible to tell if a mech is really bent or not from typical cameraphone photos; there is so much barrel distortion when you use short focal length lenses close-up, straight mechs look bent and bent mechs look straight.

If you want to post a more useful photo or two, take some from several yards away and then zoom in and crop out the rubbish you don't want; the barrel distortion will be somewhat reduced. A good trick is to jam a straight edge (ruler?) between the large sprocket and the spokes; the mech should lie parallel to that.

cheers
-------------------------------------------------------------------------------
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~

James Up Hill
Posts: 43
Joined: 7 Oct 2019, 12:39pm

Re: Lost: two gears... Help please adjusting derailleur

Postby James Up Hill » 23 Oct 2020, 11:47am

Thanks all for the help. Very much appreciated!