Originally Posted by
fcormier
If you choose to go the 8 speed route, you may need to change the derailleur as I found out that a 7 speed derailleur (like my Shimano STX) does not have enough range to reach the inner cog (the biggest one).
I have an STX "7-speed" rear derailleur on an older road bike running an 8-speed cassette and it has no problem whatsoever shifting to the largest cog.
If you are having that problem, it's likely your inner limit screw needs to be adjusted.