Originally Posted by ParamountScapin
Just picked up a great little Trek 2300 for my daughter in a 50cm size. It is all Shimano 600, which is a 7-speed system. I want to up-grade to STI shifters and am wonder what all I need? Based on my very limited Shimano knowledge, I am guessing that, like Campy, a Shimano 8-speed fits in the same width as a 7-speed. Is that correct? That I will need the STI shifters (duh!), an 8-speed cassette and the matching 8-speed rear derailleur and chain. Is my guessing correct? Thanks for your help and have a Merry Xmas!!
7 speed sora shifters are avaialble. You can't stick a shimano 8 speed cassette on a 7 speed freehub Hub body is too narrow... You can get a loose cog 9 speed shimano cassette,remove a cog and spacer and it will fit. Get a 9 speed chain and shift it with 9 speed STI.No need for a new RD unless the old one is wore out and sloppy. You may need a new FD.