Bicycle Mechanics - SRAM APEX cassette (11-32) w/ Dura Ace 7800 RD?

Does anyone know if a Dura Ace 7800 RD would work with the new SRAM APEX 11-32 cassette? I already have the DA RD. Thanks for your responses.

Mike

Maybe but not likely. If you really want to use that cassette, buy it, try it, and if it doesn't work then buy a new rear derailler.

I agree, I don't think it will work. I was looking at the APEX as well and did some research for using it with my existing DA RD. Max tooth capacity on the DA RD is 28, based on the manual. However, I've heard of people using a 30 tooth rear cassette with the DA RD. Another option I considered was using a MTB RD which generally has a wider range, but then I got into the 9 speed issue...

Any Shimano MTB rear derailler with work fine with a 10 speed cassette and will allow you to use a 32T rear cog. Shimano's rear deraillers have never been "speed" specific. There is no functional difference between an 8, 9, or 10 speed rear derailler other than finish.

Thanks for the replies.

Mike

The model 7800 good to 27t but 28t works a 32t cassette will require you to use a Long or at least a Med. cage RD.

The model 7800 good to 27t but 28t works a 32t cassette will require you to use a Long or at least a Med. cage RD.

A long cage derailleur has the same cog size limitation as a short cage derailleur. There are no Shimano medium cage road derailleurs but any Shimano mountain type derailleur can handle up to a 34t big ring.

i built up a few new bikes with the apex group. works well, long term durability will need to be tested. i believe the largest 2 cogs of the cassette are pinned to a alloy carrier. to the OP, you will need a shimano mtb type derailleur,

Any Shimano MTB rear derailler with work fine with a 10 speed cassette and will allow you to use a 32T rear cog. Shimano's rear deraillers have never been "speed" specific. There is no functional difference between an 8, 9, or 10 speed rear derailler other than finish.
Assuming he has a 10 speed STI shifter, would that introduce an issue if he used an MTB RD?

Assuming he has a 10 speed STI shifter, would that introduce an issue if he used an MTB RD?

As long as he sticks with Shimano, it'll work fine.