How to tell if a rear mech is bent ?

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CubeCrazy

How to tell if a rear mech is bent ?

Postby CubeCrazy » Tue Dec 04, 2012 14:17 pm

Hey guys.

Wondered if someone could help me.

My last ride out I was blitzin along when I gets this long stick stuck in my derailleur, so I hops off the bike and I had to pull it out with some force, everything felt ok.

The next time I come to ride my bike its just not indexing correctly, usually this is fixed with a couple of turns of cable adjuster but the chain came off the largest cassette ring.

So I went about setting up the high and low stops and taking the slack out of the cable, what used to be a 5 min job was a 2 hour job and its still not perfect.

I am wondering if I bent my rear mech somehow when I pulled the stick out ? and I also wondered if there was a way to test to see if I had bent it out of alignment ?

I have gone up and down the cassette with the bike on the stand and in one particular gear it makes a racket and it dont sound right to me but maybe it is, so heres some pics to explain the gear its in and if this looks right:

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I hope its not ruined its an XT one and not even 6 months old.

Any tests I can perform on this one ?

Cheers in advance.


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zx6man
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Re: How to tell if a rear mech is bent ?

Postby zx6man » Tue Dec 04, 2012 14:41 pm

Can you not just try bend it back. Mine was damaged at the knuckle so could never get it straight, that looks to be just the cage. I could tell better from the rear, the cogs should be lined up

CubeCrazy

Re: How to tell if a rear mech is bent ?

Postby CubeCrazy » Tue Dec 04, 2012 14:41 pm

Oh noooooooooooooooooooooooooo :? :cry:

Damn ......

Well, thank you for confirming that mate... am gutted... lol.

Maybe now is time to go single speed anyway.

Many thanks 8)

CubeCrazy

Re: How to tell if a rear mech is bent ?

Postby CubeCrazy » Tue Dec 04, 2012 14:42 pm

I'll give that a bash then ZX6Man, hopefully keep me running for now :D

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zx6man
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Re: How to tell if a rear mech is bent ?

Postby zx6man » Tue Dec 04, 2012 15:00 pm

You will tho in BIG/BIG like that see it cross over quite severly.

Chunkers1980
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Re: How to tell if a rear mech is bent ?

Postby Chunkers1980 » Tue Dec 04, 2012 15:08 pm

Question is why did you "pull it out with some force" and not tease it out?

It's a precision part with many pivots.

CubeCrazy

Re: How to tell if a rear mech is bent ?

Postby CubeCrazy » Tue Dec 04, 2012 15:11 pm

I tried that for 15 mins chunkers and it wasnt havin it, was well jammed in there, rest of ride home was fine and it worked ok, but after a few days I get the bike out again and all is not ok.

Contemplating going 1 x 9 cant be arsed with all this, but its such a cost, I think I will just get a new rear mech and be done with it.

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The Rookie
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Re: How to tell if a rear mech is bent ?

Postby The Rookie » Tue Dec 04, 2012 15:19 pm

In that case keep the old one for Jockey wheels and other sundry bits you are occasionally very grateful for keeping!

CubeCrazy

Re: How to tell if a rear mech is bent ?

Postby CubeCrazy » Tue Dec 04, 2012 15:27 pm

I'm trying to convince myself I can fix this and its not bent, but am not doing a very good job lol.

I just took chain off this is what it looks like, just cant get alignment with the damn thing.

Image

OK so I best order a new mech.

Anyone know how much am looking at if I was to go 1 x 9 ? just a rough cost ? does it have to be expensive ?

Chunkers1980
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Re: How to tell if a rear mech is bent ?

Postby Chunkers1980 » Tue Dec 04, 2012 15:30 pm

Looks like your hanger is not too striaght either. From 20 - 120 quid for the mech.

alfablue
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Re: How to tell if a rear mech is bent ?

Postby alfablue » Tue Dec 04, 2012 15:31 pm

Yes, the hanger is bent, why not try that first? £10-£12.

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zx6man
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Re: How to tell if a rear mech is bent ?

Postby zx6man » Tue Dec 04, 2012 15:34 pm

Doesn't look like just the cage, that top jockey wheel looks well out. Hard to tell if its mech or even hanger (looks a bit out) .

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.blitz
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Re: How to tell if a rear mech is bent ?

Postby .blitz » Tue Dec 04, 2012 15:35 pm

Agreed it does look bent

ime 9sp XT is ace when everything is perfect but it has zero tolerance to mis-alignment and sticky cables. I would take this opportunity to go 9sp SRAM which just keeps shifting and shifting and shifting until it blows up.

But nothing will work if the hanger is bent

Chunkers1980
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Re: How to tell if a rear mech is bent ?

Postby Chunkers1980 » Tue Dec 04, 2012 15:38 pm

What? and buy a new shifter too. He's already whinging about the price of the mech.

Chunkers1980
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Re: How to tell if a rear mech is bent ?

Postby Chunkers1980 » Tue Dec 04, 2012 15:39 pm

Oh and rubbish.

CubeCrazy

Re: How to tell if a rear mech is bent ?

Postby CubeCrazy » Tue Dec 04, 2012 15:51 pm

Ya never have much positive to say do ya chunkers ?

Right guys.. I taken some pics of the hanger and it does seem bent but can this amount cause something so drastic ?

I have the original hanger so am gonna bang that on and see whats what, god I hope thats all it is.

Image

Image

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Image

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zx6man
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Re: How to tell if a rear mech is bent ?

Postby zx6man » Tue Dec 04, 2012 15:53 pm

Middle (of bottom 3 ofc) pic shows it best mate, could be a winner having a "spare" already. :-)

CubeCrazy

Re: How to tell if a rear mech is bent ?

Postby CubeCrazy » Tue Dec 04, 2012 15:57 pm

Yeeha am on it :D

Thanks everybody

alfablue
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Re: How to tell if a rear mech is bent ?

Postby alfablue » Tue Dec 04, 2012 16:06 pm

yes, that small bend could be responsible, as by the time you get down to the lower jockey wheel that would deviate quite a bit.

Always good to keep a spare hanger!


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