compact chainset - short or long cage rear mech?

[e-rider]

assuming a 34/50 compact chainset and 12-27 cassette (105 5600 groupset)

will this work with a short cage rear mech or will it require a med/long cage?

Looking at bikes with compacts, most have short cage but some have long cage rear mechs. I guess this depends on the cassette size and the design of the rear mech.

 

[ianrauk]

Short cage will work fine.

 

[Rob3rt]

Short cage.

 

[Andy_R]

Long cages tend to be used on mountain bikes with small granny rings, to take up the slack, so no need for one on a road bike with a compact chainset.

 

[e-rider]

Long cages tend to be used on mountain bikes with small granny rings, to take up the slack, so no need for one on a road bike with a compact chainset.

the 34T isn't far off a granny ring!

 

[Andy_R]

the 34T isn't far off a granny ring!

we're talking 20 or 22 teeth granny ring, so quite a difference in size. 34 teeth is more like a middle ring.