10 speed brifters with 8 speed rear der?
04-26-06, 01:50 AM
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10 speed brifters with 8 speed rear der?
Are 10 speed brifters compatible with an 8 speed rear derailleur. Specifically, I'm thinking of using DA 10speed STI levers with an old DA 8 speed rear derailleur. Shimano will say that the rear derailleur needs to be upgraded because the 2 are not compatible, but does anybody have any different experience?
04-26-06, 02:12 AM
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Originally Posted by bellweatherman
Are 10 speed brifters compatible with an 8 speed rear derailleur. Specifically, I'm thinking of using DA 10speed STI levers with an old DA 8 speed rear derailleur. Shimano will say that the rear derailleur needs to be upgraded because the 2 are not compatible, but does anybody have any different experience?
Tim
04-26-06, 06:47 AM
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Deraillers don't have speeds - that's a marketing distinction. Deraillers have amount of cable pull per amount of lateral movement. And all Shimano rear deraillers since 6-speed indexing has the same amount of cable pull... except pre-9-speed Dura Ace. If your rear derailler was an originally-designed-for-6-speed 105 from 1987, it would work fine. As things stand, you'll need a new rear derailler if you want to go to 10-speed shifters and cassette. But any Shimano rear derailler other than 7- and 8-speed DA will work.
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"c" is not a unit that measures tire width
"c" is not a unit that measures tire width
04-26-06, 07:25 AM
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Thanks Tim & Tim. Good info. Do you know where I can find the amount of cable pull for DA8 rear deraillers, and other deraillers?? There's got to be some sort of derailler database of some sort out there.
04-26-06, 08:26 AM
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It's not worth knowing exact cable-pull stats, IMO. You just need to know which things are compatible. As long as you know that 8-speed D/A will only work (indexing) with 8-speed D/A, and all other Shimano (including 9- and 10-speed D/A, not 7- or 8-speed) will work with each other, then you're good to go.
Sheldon has a compatibility article
https://www.sheldonbrown.com/speeds.html
Sheldon has a compatibility article
https://www.sheldonbrown.com/speeds.html
04-26-06, 10:41 AM
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The Dura-ace pre-9-speed stuff has different cable pull. If use a Dura-ace 7400 series (6,7,or 8-speed) rear derailer with 9-speed shifters, it will actually shift 8-speed spacing (and you'll have an extra shift that won't do anything). If you use it with 10-speed shifters, it will shift 9-speed spacing. https://www.sheldonbrown.com/dura-ace.html#indexing
