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Hello,
I'm thinking about gradually upgrading my current transmission..
Currently on a Giant SCR 3 (2007) with Tiagra Rear Mec, Sora triple front and a generic crankset...
I'd like to upgrade to 105, probably starting with the chainset and front mech. Are there any compatability issues I should be aware of? And will I need to change the bottom bracket too?
Grateful for any advice....