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Old 06-27-07, 09:40 AM   #1
ivegotabike
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what good does alternative cable routing do?

http://sheldonbrown.com/dura-ace.html

So, Sheldon, (or anyone who knows realy) explain how bending a cable up through the pinch bolt instead of going right through changes anything about compatibility.
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Old 06-27-07, 09:48 AM   #2
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It alters the derailleur's pull ratio.
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Old 06-27-07, 10:20 AM   #3
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By moving the point where the cable is anchored, you change the distance the derailleur moves when you pull the cable a certain amount. In other words, when you move the shifter one click, the different anchoring point causes the cable pull to have a slightly different affect; in the case of alternate cable routing, it causes the derailleur to move slightly further with each click of the shifter-
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Old 06-27-07, 11:03 AM   #4
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Let me say it another way:

If you anchor the shift cable closer to the pivot the same amount of cable pull will move the derailleur farther. It doesn't take very much to make a difference.
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Old 06-27-07, 11:03 AM   #5
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The old DA shifters pulled less cable/shift, so this routing pulls enough cable for you to be able to use the other model RDs w/early DA shifters.

Too bad it's not the other way around. Plenty of old DA RDs around, just not enough 7&8s DA shifters
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Old 06-27-07, 06:42 PM   #6
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Quote:
Originally Posted by vpiuva
Plenty of old DA RDs around, just not enough 7&8s DA shifters
Use a 9-speed shifter with your 8-speed DA derailleur. Spacing of all Shimano 9-speed rear shifters (DA, Ultegra, 105, mountain...) is identical to the spacing of 8-speed DA shifters and derailleurs.
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Old 06-27-07, 07:20 PM   #7
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Quote:
Originally Posted by Michel Gagnon
Use a 9-speed shifter with your 8-speed DA derailleur. Spacing of all Shimano 9-speed rear shifters (DA, Ultegra, 105, mountain...) is identical to the spacing of 8-speed DA shifters and derailleurs.
I know, just not quite correct when you're anal on a resto
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