Rear derailleur question

[tjk23]

What Shimano rear derailleur so I need to run a 34 tooth rear cassette?

[oliver1850]

Answer will depend on number of cogs in your cassette and what shifters you are using.

[tjk23]

Dura Ace 9000 11 speed with 52/36 crank.

[oliver1850]

I don't know if an 11 speed cassette with a 34 large cog exists. If you can make do with a 32, a 6800 GS cage RD is rated for 37 total capacity and 32 large cog. You might get away with it on a 34 if the cassette is available.

[dem]

Doing an IRD 11-36 11 speed cassette with a 6870 medium cage and Wolftooth Roadlink.

RoadLink: https://www.wolftoothcomponents.com/products/roadlink
IRD cassettes: http://www.interlocracing.com/cassettes-freewheels/11-speed-elite-cassette-shimano-compatible

Probably gonna try to squeeze an 11-40 in there next.

http://www.haphazard.com/bikes/slow.jpg

[RudAwkning]

Tiagra 4700 rear mech is good up to 34t per Shimano specs. It shares the same geometry as 11 speed Shimano. I'm currently using a Tiagra rear derailleur with a 48/34 crankset and an 11-36 cassette.

[weisan]

I am currently running a Tiagra 4600 with 10 speed 11-36 cassette and compact crank - zero issue.