Can you use an 8spd cassette on a 10spd hub?

[oysterkite]

SRAM 2:1 RD's shift the same amount, the difference is at the shifter end, if the rd shifted twice as much as a shimano rd you would have a v strange looking cassette (ie it would have v large gaps).

[javadude]

Duh, my apologies oysterkite, I meant Sram 1:1 is different, not 2:1 which is the Shimano standard.

[LeTurbo]

I'm starting to understand why I just take my bike to the lbs and fork out the dosh.

[Slowone]

I'm starting to understand why I just take my bike to the lbs and fork out the dosh.

Alternate is to make friends with the mechanic and pay him / her directly ........

can save quite a bit and there is convenience of being able to go to the mechanic on a Sunday ........

[Tiny K]

I was going to answer but it seems that it has been done already but just to recap - only diff between 8 and 10 speed cassette is the spacers between the gears. 10 speed narrower naturally - hence narrower chain for 10spd. FD and RD are just slaves of the shifters - they do what they are made to do. Top and bottom stoppers prevent the chain from jumping off. I don't know if there is a chainring thickness difference? Anybody know?

[Tankman]

10 speed front derailleurs are actually narrower than 9 and 8 speed, so an 8 speed chain will have more rub with a 10 speed derailleur, but it will still work.

 

You are totally wrong about rear derailleurs though. For instance, an 8 speed dura ace rear derailleur will ONLY work with 8 speed Dura Ace shifters. Also, 11 Speed campag rear derailleurs dont work all that well with 10 speed shifters. Correction, apparently they do work. But still its not a blanket statement, you have to try it for yourself. For instance, Sram 1:1 derailleurs look just like any other derailleur but shift twice the distance for the same amount of cable pull as a Shimano derailleur.

 

Lets take 8 speed out of the equation. The chainrings of a 8 speed bike is thicker to accommodate for the thicker chain.

Most bikes these day are either 9 or 10 speed. The difference between a 9 or 10 speed is so minimal that it would not matter what if you are using a 9 or 10 speed FD. If the chain rubs, you have not done your setup properly!

 

I am not totally wrong about RD as you can see in your own statement above. Ok I admit, I havent tried playing with 8 speed RD's before but as I said who uses them?

 

The way Sram or Shimao shifts has nothing to do with what I said, I am under the impression you know by now to use Sram shifters with Sram FD's and RD's and Shimano with Shimano.

 

Oh and I have tried it for myself. I am using a 9 speed Dura Ace RD on a 10 speed bike with 10 speed shifters, no problem! And when Shimano brings out their 11 speed, Ill slap on a 11 speed chain, cassette and shifters and my "9 speed" RD will still work. (without chaning FD or chainrings)

 

The width of the cassette has not increased, thus the RD does not need to shift any further than before and the increments of shifting is done by the shifter.

[Tankman]

For instance, an 8 speed dura ace rear derailleur will ONLY work with 8 speed Dura Ace shifters.

 

I am still curios as to why you say only.

Because a 9 or 10 speed RD will work with your 8 speed shifters. The RD will still shift only 8 times as we already established the increments and shifting is done by the shifters.

So why will a 8 speed RD not work with 9 Speed shifters?

[javadude]

I am still curios as to why you say only.

Because a 9 or 10 speed RD will work with your 8 speed shifters. The RD will still shift only 8 times as we already established the increments and shifting is done by the shifters.

So why will a 8 speed RD not work with 9 Speed shifters?

 

And i'm with you on 9 and 10 speed chain width, the differences are very small.

 

Regarding the 8 speed DA, I also thought it would work until I spent a few frustrating hours trying to get my rear der working with ultegra shifters. Then I read about it on Sheldon Browns site where he stated that the 7400 series rear derailleur is only compatible with 7400 series shifters. Like I said, its something to do with the geometry of the derailleur. You are right about the rest of Shimano though, you can mix and match any derailleur with any shifter.

 

Having said that, apparently the new 10 speed MTB derailleur's don't work with 9 speed shifters. This is just what I've read on other forums, haven't got any personal experience with this.

 

I have also been unsuccessful shifting Campagnolo derailleur's with Shimano shifters, although one combination I know works is using Campagnolo 10 speed shifters to shift sram 10 speed road derailleurs.

 

 

Heres a link to Sheldons site about compatability:

 

http://www.sheldonbrown.com/speeds.html

 

And the link to his Dura Ace page:

 

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

 

Its a bit out of date because Sheldon is no longer around.

Edited February 2, 2011 by velo

[Tankman]

Yea I see in Sheldon's article:

 

"Shimano Dura-Ace models from 1996 and earlier (pre "9-speed") need to be used with matching shifters"

 

I havent had much contact with any pre 1996 gear