I tried looking on google and can't seem to find the answer so here it goes. Can you fit the new Ultegra 6800 11spd or Sram Force 22 on say a 2010 frame that currently has 105 on it? Do I need to do something crazy or do I just forget the idea and save for a new ride? I know I can't just replace one piece but am looking at the entire group minus the crank since it won't fit my MegaExo. Speaking of cranks am I understanding it correct that it will need a different size ring and is this something I can just change the rings on my current crank?
Maybe someone else can help you with the crank/chainring question as I'm unsure about that issue.
But 11 speed will work on any road/tri bike. There is nothing special required about the frame other than it has a derailleur hanger in the back (fixie/single speed frames won't work) and either an area for a clamp on or braze on front derailleur. These things are not specific to 11 speed...they are specific to road/tri bikes. Campy has been 11 speed for a long time and people have no problem swapping between 8/9/10 speed Shimano/SRAM and Campy on the same frame.
What you do need to be concerned about for 11 speed (or if you wanted to move to Campy) is your rear wheel. Certain free hub bodies can/can't accomodate an 11 speed cassette. You can check with your wheel manufacturer on those specifics.
You can use your current crank.... it'll work. The Shimano 11 speed requires a different hub than the 10 speed though. Some newer wheels accommodate both, some you can swap out the freehub body, and some, well you're out of luck. If Campy could fit the 11 speed on the same spacing as the 10 speed, I can't for the life of me figure out why Shimano decided to be a PITA and develop yet another standard...My Race Log