#!markdown
Sounds like you're experiencing less-than-optimal shifting due to your
b-tension screw being adjusted outside the derailleur's normal range. This is
a common issue with the extended range 40 and 42 tooth cogs, and why OneUp
started producing the RAD cage for Shimano derailleurs. For now, those with
SRAM derailleurs don't have that option, which is part of why I chose to go
with the 28 tooth up front. This achieves a lower gear ratio than your 32/40
setup but retains factory shifting. If you have a triple crank, AbsoluteBlack
makes a 64bcd "XX1 style" ring in 26 and 28T, though you compromise on
chainline with this one.
Aug. 20, 2014, 12:31 p.m. - Morgan Taylor
#!markdown Sounds like you're experiencing less-than-optimal shifting due to your b-tension screw being adjusted outside the derailleur's normal range. This is a common issue with the extended range 40 and 42 tooth cogs, and why OneUp started producing the RAD cage for Shimano derailleurs. For now, those with SRAM derailleurs don't have that option, which is part of why I chose to go with the 28 tooth up front. This achieves a lower gear ratio than your 32/40 setup but retains factory shifting. If you have a triple crank, AbsoluteBlack makes a 64bcd "XX1 style" ring in 26 and 28T, though you compromise on chainline with this one.