10spd compatibility

Brennus wrote:Brennus, what does an old article about mountain bike shifting have to do with this conversation?

At the top of this thread I read the following text:

"Have a Jamis Renegade and love the bike. Came with Shimano Tiagra 10spd.
Looking for more chain tension to reduce chain slap. Someone recommended a older 9spd XT derailleur."

After reading that I posted some text from Shimano and SRAM regarding using 9 speed derailleurs with 10 speed shifters.  The intent of that post was to provide some credible information regarding the combination of 9 speed derailleurs with 10 speed shifters.  Hopefully this will encourage folks who want to use that combination of shifter/derailleur to not do so.

I'm tracking, but there's two problems:

1) That article is entirely about mountain bike shifters. We're talking road shifters here.

2) A 9 speed Shimano XT rear derailleur will work well enough with 10 speed Shimano road shifters. There's really no reason to do that unless you need a mega range. I don't feel like the spring/cage tension is any better than a Shimano road rear derailleur in the high tension setting. The cable pull is a teeny bit less than the 9 speed it was intended to work with, but if you set it to work perfectly in the middle of the cassette, it will still shift to both the lowest and highest gears. It's not perfect, but many people have done it without too much complaining. I agree with the linked article that it won't even be close to working correctly if you pair a 10 speed Shimano mountain shifter with a 9 speed Shimano mountain derailleur.

Brennus wrote:Brennus, what does an old article about mountain bike shifting have to do with this conversation?

At the top of this thread I read the following text:

"Have a Jamis Renegade and love the bike. Came with Shimano Tiagra 10spd.
Looking for more chain tension to reduce chain slap. Someone recommended a older 9spd XT derailleur."

After reading that I posted some text from Shimano and SRAM regarding using 9 speed derailleurs with 10 speed shifters.  The intent of that post was to provide some credible information regarding the combination of 9 speed derailleurs with 10 speed shifters.  Hopefully this will encourage folks who want to use that combination of shifter/derailleur to not do so.

10 speed Dynasys shimano mountain cable pull is different from 10 speed shimano road.  Don't confuse 9 speed mountain derailleur incompatibility with 10 speed Dynasys with the compatibility between 9 speed mountain and 10 speed shimano road (Other than Tiagra 4700 which is different).

Many of us run 9 speed mountain rear derailleurs on 10 speed Shimano road systems. My commuter bike has a Deore 9 rear derailleur and shifts perfectly with the 105 5700 shifters.  My wife has the same 9 speed derailleur on her Warbird with DA 7800 shifters and again works perfectly on a 10 speed cassette.

Brennus wrote:Brennus, what does an old article about mountain bike shifting have to do with this conversation?

At the top of this thread I read the following text:

"Have a Jamis Renegade and love the bike. Came with Shimano Tiagra 10spd.
Looking for more chain tension to reduce chain slap. Someone recommended a older 9spd XT derailleur."

After reading that I posted some text from Shimano and SRAM regarding using 9 speed derailleurs with 10 speed shifters.  The intent of that post was to provide some credible information regarding the combination of 9 speed derailleurs with 10 speed shifters.  Hopefully this will encourage folks who want to use that combination of shifter/derailleur to not do so.

The original topic relates only to Shimano road derailleurs. Shimano road 7,8,9,10 are mostly compatible, Tiagra 4700 being an exception. MTB changed with 10/DynaSys.