Question on changing rear derailleur
Obviously, this is my first post. So, quick intro...petite 6' 1" 290 clyde just getting back into biking to do the obvious-get in better shape and lose weight. Got a good deal on a GT Transeo Disc 2.0 because it had a busted rear derailleur. Don't know how it broke, maybe in shipping, but it is a non-starter.
Seeing as how I am not the strongest yet, I have a 9-speed cassette (got from a buddy-Shimano XT 11-34) that I was thinking of replacing the 8-speed 11-32 currently on the bike along with a new Shimano SLX RD-M662 derailleur. Or should I just replace the derailleur with the SLX and leave the 8-speed alone?
Thoughts and insight are appreciated....been lurking for a while and have learned much and received much inspiration from this bunch.