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[Closed] Road Bike Gear Cables

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[#4182651]

So I have a niggly slow down shift on my 7900 Dura Ace rear derailleur. Not a major problem but enough to be a bit annoying. Up shifting is fine.

Googling around it seems to be a bit of an issue with 7900, some people have suggested its down to cable friction which would make sense.

So I'm looking at some aftermarket cable sets, Gore, Nokon etc. Anyone have any experience with these? Or a waste of money? Or anything else I should look at?


 
Posted : 21/07/2012 1:23 pm
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Shimano SP41 outer with stainless and coated inners should be fine. Replace both for a fresh start.
With a road bike you will only have a couple of pieces of outer...make sure the rear piece is the correct length...check with the Shimano Tech Docs for the mech.

PaulD


 
Posted : 21/07/2012 1:28 pm
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hmm sp41 is what i have!


 
Posted : 21/07/2012 1:32 pm
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Stick a a [url= http://www.chainreactioncycles.com/Models.aspx?ModelID=3318&utm_source=Google&utm_medium=Shopping&utm_name=UnitedKingdom ]cable oiler[/url] in and give it a wee blast of GT85 now and again.


 
Posted : 21/07/2012 1:38 pm
 cp
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Has it always been this way?

By slow down shift, are you talking about to the larger sprockets I.e. to a lower gear? The cable is being pulled by the shifter this way so weird you'd be having problems in this direction. During upshifts, so smaller sprockets, the mech is pulling cable through from its spring force, and is what tends to give shifting issues if you have excess cable friction.


 
Posted : 21/07/2012 1:43 pm
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I mean from larger to smaller sprockets, i.e where mech is pulling the cable


 
Posted : 21/07/2012 1:53 pm
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[smug 7800 user]

hmm sp41 is what i have!

Yes, but it won't be fresh, fresh inner and outer will probably sort it, and SP41 is a fraction of the cost of nokon.

It's sticky in 7900 because shimano went with fashion and put the gear cable under the bar tape, which adds friction. Apparently thye've cured it on 9000 with more linear mech movements, a new proprietary polymer coating on the cables and cable routing through the shifter. So the only option of those three is slicker cables to keep 7900 working well.

[/smug 7800 owner]


 
Posted : 21/07/2012 1:54 pm
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It's sticky in 7900 because shimano went with fashion and put the gear cable under the bar tape, which adds friction

I wondered if it was something like that, was 7900 first DA with hidden gear cables? I'm not sure.

I've read about some people replacing the casing in this area...


 
Posted : 22/07/2012 8:40 am
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Shimano make an expensive grease that you are Ment to use when fitting cables to the da shifters
But have always had good results with rock and roll cable magic


 
Posted : 22/07/2012 8:45 am