's Forum Archives - Components

Archive Home >> Components(1 2 3 4 5 6 7 8 9 10 )

9 speed shifters on 8 speed group?(5 posts)

9 speed shifters on 8 speed group?aaronpv2
Jun 4, 2002 5:06 PM
Yeah, I know get a complete 9 speed system, I'm working on it.
Anyway just picked up a set of DA STI 9spd. shifters, haven't arrived yet. My current set up is Ult STI 8spd. shifters, DA 9spd. R. Der., Ult 8spd. Frt. Der, DA 9spd. cranks with rings and an HG90 8spd. chain. This set up currently runs pretty flawlessly with the exception of some chain rub in the frnt. der. which is pretty acceptable.
The question is can I use the DA STI 9spd. with this current 8spd. setup. My thinking is that the limit screw for the R. Der. when on the lowest gear, biggest cog, should automatically prevent me from being able to use the last click or 9th gear posisiton on the shifter, effectively limiting it to 8spd.s.
I have checked several sites, Sheldon Brown of Harris Cyclery has a shifter, cassette matrix and it indicates that it should work. Any thoughts.
Okay, I admit it.szybki
Jun 4, 2002 5:42 PM
I have tried this too. It doesn't work, the STI spacing is off. You'll never be able to adjust the cable tension to the point where it won't rattle somewhere. Besides, it looks like you only need a new cassette and chain and you'll have a complete 9sp drivetrain (front der. won't matter) Why not go that route? You can pick up a Ultegra cassette from Supergo for about $37 (I think, I just bought one last week). You have wheels that won't take a 9sp cassette? Save yourself some hassle and just get the cassette.
Ditto - no way.Matno
Jun 4, 2002 6:13 PM
Aaron, I'm not sure where you got the faulty info, but it is definitely wrong. The derailleur limit screw won't do a thing since the overall spacing for 8 and 9 speed is the exact same. However, the spacing between gears is different because they had to fit 9 gears into the same width. On the bright side, you don't have to get a new hub. Just a new cassette and chain, as was mentioned. I just got an Ultegra cassette from JensonUSA for $32 and an HG93 9speed chain for $15 from the same place. You might be able to make 3 or maybe even 4 gears work marginally well with the setup you suggest, but you'll likely have lots of unintentional shifts and I can pretty much guarantee lots of aggravation, not to mention premature wear on your chain and cassette.

Bottom line: Don't bother.
I will work but.........Dave Hickey
Jun 5, 2002 5:03 AM
It works. The Rear Der. cable is attached on top of the screw instead of below. Shimano's rear der. instructions show how it's done. I've used it on many bikes and it shifts fine but as the above posters have said, all you need is a nine speed cassette and you have a nine speed drive train.
re: Holy Cow...............!!Rusty Coggs
Jun 5, 2002 5:05 AM
Didn't ya get instructins with that 9 speed DA rear derailer.It has an alternate cable mount position to allow it to be used with an 8 speed cassette using your 9 speed DA shifters or any other shimano 9 speed shifter for that matter.sheldons DA article speaks to the alternate cable mount position on the 9 speed DA rear derailer.