Rear derailleur

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richard21172
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Joined: 26 Jul 2013, 6:56am

Rear derailleur

Post by richard21172 »

The rear derailleur slightly touches the spokes when its in the biggest gear. I have checked the hanger and that is perfectly straight. Adjusted the L screw as much as I can. tried a different rear wheel but it is always very close to the spokes. More noticeable when pedaling with any type of force, the derailleur slight touches the spokes. I have looked at other bikes and the clearance is pretty significant compared to mine so not sure what to try next. Any help greatly appreciated. Many thanks in advance
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531colin
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Location: North Yorkshire

Re: Rear derailleur

Post by 531colin »

If pedalling hard makes something move, then something is loose.
Spokes slack?
Bearing play?
Q/R slack?
Axle broken, held by the Q/R?
(frame cracked.... :shock: ...?)
richard21172
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Joined: 26 Jul 2013, 6:56am

Re: Rear derailleur

Post by richard21172 »

Checked all these and all seem OK. When adjusted the maximum distance I can adjust it to is about a mm (if that) between derailleur and spokes, if that. This doesn't seem right. Therefore there is no or little tolerance
Valbrona
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Re: Rear derailleur

Post by Valbrona »

If your dropout/gear hanger is bent I would have thought your testing with a gear hanger alignment gauge would have shown that up because anything else is guesswork.
I should coco.
richard21172
Posts: 55
Joined: 26 Jul 2013, 6:56am

Re: Rear derailleur

Post by richard21172 »

It is a new hanger so it's definitely not bent
Brucey
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Joined: 4 Jan 2012, 6:25pm

Re: Rear derailleur

Post by Brucey »

but the frame might be bent where the hanger screws on...?

A photo would be useful?

It might help if you say which combination of hub, cassette and rear mech you are using too.

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
Valbrona
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Re: Rear derailleur

Post by Valbrona »

Have you had a truck roll over your rear wheel in the past week or two? Or put another way, had any crashes? Bike toppled over?
I should coco.
richard21172
Posts: 55
Joined: 26 Jul 2013, 6:56am

Re: Rear derailleur

Post by richard21172 »

I'll post a pic tomorrow as it's a bit dark now.. :-) it's a 105 mech, shimano cassette, moda carbon bike. I did have a knock hence the hanger broke and was replaced. No other damage to the bike or derailleur. The gap between derailleur and spokes was the same prior to the knock. Maybe a tad bigger but not significant
Brucey
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Re: Rear derailleur

Post by Brucey »

what make of rear hub are you using?

Which shimano cassette....?

which generation of 105...?

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
richard21172
Posts: 55
Joined: 26 Jul 2013, 6:56am

Re: Rear derailleur

Post by richard21172 »

Not 100% sure but standard hub of R500 shimano wheels, 10 speed shimano 105 cassette, shimano 105 5701 derailleur. Hopefully this is the info :-/
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cycleruk
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Re: Rear derailleur

Post by cycleruk »

Looking from the back of the bike the derailleur should be perfectly vertical.
Is the wheel rim in the centre of the "dish" ?
You'll never know if you don't try it.
Brucey
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Re: Rear derailleur

Post by Brucey »

all those parts are pretty much designed to work together so that is a bit odd.

By any chance has someone inverted the inner cage plate on the rear mech? This would reduce the clearance to the point that it mightn't work at all....

BTW 10s #1 sprockets are dished so the mech sits closer to the spokes than with 9s systems.

cheers
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NATURAL ANKLING
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Re: Rear derailleur

Post by NATURAL ANKLING »

Hi,
When the derraileur is quite worn it leans into the wheel :?:
Slacken the cable / put it in top gear and grab the jockey cage at bottom and move in and out from wheel :?:
On a new derraileur there should be no play, it will be obvious if there is play as you should be able to straighten the cage to a normal (perpendicular with ground) position when you pull it out gently.
Or even in gear nearest wheel spokes you will have play and it will be evident by rocking jockey cage in and out.

Idealy pick a gear which allows the cage to hang down furthest to floor, so the jockey cage is up right, and the derraileur body is also hanging down further to and view from side.
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Vantage
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Re: Rear derailleur

Post by Vantage »

+1 for possibly worn mech. I thought mine was fine till a gear shift had it scraping the spokes and almost mangling the new rear wheel. The new mech has a lot less play.
Bill


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richard21172
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Joined: 26 Jul 2013, 6:56am

Re: Rear derailleur

Post by richard21172 »

Some pics that maybe show the problem.
Attachments
photo 1.JPG
photo 1.JPG (35.07 KiB) Viewed 1273 times
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