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Dura Ace shifters

Old 07-21-11, 04:00 PM
  #1  
mststationary
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Dura Ace shifters

When Dura Ace was making 9spd stuff they came out with some barend shifters (SL-BS77) with a sticker on it that read something like, "Compatible with RD-7700(9spd) and RD-7400(8spd)." It seems like it's they're saying that these thing can index with 8spd and 9spd systems, and I don't they are talking about friction shifting. I don't know very much about how these systems work, but it it's my understanding that 9spd indexed shifters don't work with 8spd systems, and vice versa. If anyone has any experience with these particular SL-BS77 shifters, please let me know if it is true that they can index as both 8 and 9spds, before I track down a set and potentially spend a lot of money. If this is true then...

a) can I use them with an 8spd freewheel (Sunrace or Sachs)?

b) do the 7700 9spd downtube shifters work the same way?

Thanks a lot!
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Old 07-21-11, 04:21 PM
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Al1943
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What it means is that any 9-speed Shimano shifter will work with an 8-speed Dura-Ace rear derailleur to shift any 8-speed Shimano cassette. This is because the Dura-Ace 8-speed shifters have a unique cable pull that is almost exactly the same as 9-speed Shimano shifters. Since the 8-speed Dura-Ace rear derailleur has the correct actuation ratio for the 8-speed Dura-Ace shifters it will work perfectly with 9-speed Shimano shifters to shift any Shimano 8-speed cassette, with one extra click.
Check this out for more info: https://www.ctc.org.uk/DesktopDefault.aspx?TabID=3946
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Old 07-21-11, 04:31 PM
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fietsbob
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Generically, 9 speed is a different spacing than 8.. because the additional cog
is not getting a wider hub/axle.
they already did that to get in #8 to 130mm

friction mode .. no problem ..
do you have the parts on hand?

7 is all I bother with on freewheels , Impractical past that..
Note : You have to take the last cog or 2 off to get the removal tool on..
and grip it with the wrench or hold the tool in the vise..

and, personally, I don't need a 12 t top cog ..
13 and larger are within a 6~7 speed's combinations..

Virtually everything's compatible with friction shifting.

Last edited by fietsbob; 07-21-11 at 04:40 PM.
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Old 07-21-11, 04:48 PM
  #4  
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mststationary, The 8S Dura Ace had a unique pull ratio requiring a specific shifter that was different from most other Shimano indexed road systems. AFIK there was no 8S indexing bar end shifter available for the D-A RD. The 9S bar end probably can be used to shift an 8S cassette with an 8S D-A RD.

Brad
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