[rob39]

Hi all 

looking to see if a medium cage deraileur could support a 11-34 or 36 casette

Running a 105 50-34 chainset, 105 RD 5800 GS deraileur 11sp

 

Topic

[TheBillder]

The 105 vs SRAM Rival article
The 105 vs SRAM Rival article that has been, er, re-released to a grateful audience today, also contains the suggestion that the R7000 105 medium cage derailleurs can do 40t. 5800 not very different So fill your boots with spinny gears.

[kil0ran]

34 will be fine if it’s the
34 will be fine if it’s the GS, 36 might be pushing it

[TheBillder]

I have (I think) the medium
I have (I think) the medium cage 105. Def the 5800, ~90 mm between the pulley centres. Has run 32t from new. Other bike has same size Tiagra and I switched that from 28 to 34 (& still really struggled in the Lake District!). Both shift perfectly once the B screw is adjusted to get the chain tensioning right. The 28-34 switch didn’t even seem to need a longer chain.

Alledgedly these derailleurs can cope with 40t.

[Author]

Replies