i presenty have 7800 DA group on my tt bike. i use the bar end shifters on friction mode. can i just put a 11 speed chain and cassette and be on 11 speed!!! or do i need to change the rear derailler pulley wheels???
anyone tried?
thanks!
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Not sure about the pulleys (should work since 11 speed chains are only slightly narrower) but do you have 11 speed compatible wheels? If not, you would need those as well to run the proper cassette, but on friction as long as your limit screws are set correctly, it should work.
One might ask though why? Indexing is very nice and a major benefit to the system and except for an extra mid range gear, not worth a wheel upgrade unless you are doing the whole shebang (part of your group, wheels) imho.
However, if you are super motivated to try it, and you have a wheel where you could change the freehub body to a campy compatible one like Mavics, you could change the freehub body, use a campy cassette, and an 11 speed chain and make it work theoretically.
ZInn has a bunch of nice articles on 11 speed compatibility - one below. Google is your friend.
Have fun frankenbiking!
j
thanks
wheels arent a issue, 11 speed compatible. As for indexing vs friction… friction work every times… indexing…it can be off for so many reason with traveling with bike, chaning wheels that dont have same spacing etc… i dont know how many times some of my ahtlete complain there shifting is off… or i could not get on my smallest gear etc…
i never had bad shifting for the past 4-5 years! but i understand it s a person preference. a punishement for me is…riding indexing 
as i need a new chain and new cassette anyway…why not go 11 speed.
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