Swapping chainsets Home › Forum › Bike Forum › Swapping chainsets Viewing 4 posts - 1 through 4 (of 4 total) Swapping chainsets asterixMember Is it straightforward to swap a 50/34 chainset for my 53/39 one? Would the front mech need moving or changing? I have a 9-speed 105 system. Do chainsets with hollow tech bottom brackets mean I would also have to swap the BB? Sorry if these are stupid questions… Posted 4 years ago oldnickMember Dead easy – remove pedals, remove left crank, tap out chainset, replace with new, fit pedals, drop front mech down a bit, set up front mech, maybe remove a link or two from the chain. BB stays in and you gain a spare, Shimano techdocs is your friend, or Park Tools website, or Sheldon, or… Posted 4 years ago orangeboyMember I’m guessing your older 105 uses an octalink bb ? ( are the bb cups on the outside of the frame ) ? If it does you will need new external one if you get a modern chainset A lot of road chainsets are sold without the bb unlike mtb ones Posted 4 years ago asterixMember Thanks guys – I might go for it then, its to help climb. Will check the octalink thing but I think it is one of those Posted 4 years ago Viewing 4 posts - 1 through 4 (of 4 total) The topic ‘Swapping chainsets’ is closed to new replies.