Originally Posted by
2lo8
I got the jumps mixed up apparently.
Biggest jump is actually Tourney to Claris though.
It's all debatable really. The main reason I say Sora to Tiagra is because Tiagra and up all have the new brifter hood shape, new crank style and new style front derailleur. New Sora will have those features. Tourney to Claris is another jump because of the thumb buttons (Tourney still has thumb buttons, right?)