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I bought a SP RD and BB from my LBS recently. NIB and a total of 60 $ and I let lust have the better of me. Now what do I want to do with them. Will the RD index with 8 speed DA ? It was made in 89, what were it originally meant for, 7 or 8, 126 or 130 mm spacing? Can I use the BB (english 109mm) for anything else than Suntour cranks?
 

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Not sure that RD will work

Geometry in the RD might not work with the spacing on the DA/Shimano 8-speed cassette or FW.

I'll take the BB off your hands if you can't find a use for it. As I recall it is a special taper (and I an not just saying that.)
 

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your superbe pro RD was originally designed for 7 speed(or 6), 126mm spacing. Whether or not it will do what you are trying to do I don't know. that's a real nice rear derailler.
 

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plodderslusk said:
Can I use the BB (english 109mm) for anything else than Suntour cranks?
I'm pretty sure I used a very narrow Superbe BB with an old Shimano 600 Arabesque crank. I think you should try the crank you want to use and see if it fits. Some of the fit questions would relate to chainstay geometry near the BB shell.

- FBB
 

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it sounds like you've got the bike. try it and let us know.

for starters you could attach the RD and loosen (better yet take out) the travel set screws. Then just push the derailler with your hand and see if it will hit your biggest cog (confirm that the range hits the smallest cog also).

I have met someone one here that indexes a Mavic 851 rear derailler with Dura Ace 7 speed downtubes. So mixing/matching does sometimes work with indexing.

I am skeptical on this one though (I don't think the range will be a problem, but rather the clicks all lining up with the gears)
 

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If it's an '89 then it's probably like the GPX components that came on my old Bridgestone. On the Bridgestone I combined wide 8-speed Shimano spacing with the GPX rear derailleur and 9-speed brifters. Shifts just fine, albeit with only 8 gears. The Shimano system moves about the same cable through the largest gears as the 7-speed Suntour indexed shifting system. The problem is that the Suntour system pulls the same amount of cable whether you're shifting from first to second or from sixth to seventh. They vary the spacing of the three smallest freewheel cogs. Shimano keeps the spacing between the gears the same but varies the amount of cable pulled from first through however many gears the system uses. In other words, combine Shimano shifters with Shimano spacing or Suntour shifters with Suntour spacing.
 

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Bike Dude
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bar end shifters

Couldn't he just run Shimano bar ends in the friction mode? Or, the bar ends offered from Rivendell?
 

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funct
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yes he could.

I've got a 7spd Superbe pro RD happily pulling 9spd shimano, with the Superbe Pro levers on friction.
Hub width is irrelevant.
The RD is 'dumb'. The indexing is in the shifters. As long as the limits screws will let the der reach the biggest and smallest cogs, you're fine. I wouldn't be that surprised if an 8spd SupPro RD would stretch to 10spd.
Just match the shifters to the cassette/freewheel.
 
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