I have pretty much decided to get a new racebike together for next year. The frame will be Canyons new Ultimate CF SLX, unless I get hold of a Bianchi Oltre for the same price.

But I have had some trouble on deciding what groupset to use. I have ridden Shimano for my whole racing career and I intend to keep it that way. I currently ride a 7900 group which I like alot but I do believe that Di2 is the way to go in the future. But what Di2 groupset should I go for? 6770 with my old 7900 cranks and brakes, used 7970 or go all out with 9070? Will I actually fell any difference between Ultegra and DA?

I guess one thing to keep in mind is also wheelsets, since a 9070 group would involve new wheels aswell (and spending more money) while with 6770 and 7970 I could use my current wheelsets.

What would you have done if you were in my clothes?

i havent read much about 900 yet but do we know when its coming out to the public?

from what ive heard 6770 ans 7970 are exactly the same except for weight. obviously there are numerous differences, but from a riding/performance standpoint weight is the only "detectable" thing.

if you are swapping over your 7900 components and upgrading the shifter/derailleurs to Di2 that is the way i'd go, strictly on the savings of alot of money. but if money isn't an issue for you, why not wait for 9070 and unload the wallet going big. Plus, 9070 is lighter than the new 9000, which makes it the lightest shimano group yet.

for wheels: if you went 9070 you may be able to just get a new freehub depending on which wheels you currently run.

We can give you 500 reasons to do or not do anything, it depends on you...

are you the sensible "man I did some work myself and used some stuff I had lying around and came up with a brilliant end product" kind of guy

or are you a "I've got the best and baddest thing that will still be hard to come by on factory bikes 2 years from now" kind of guy.

I know which one I am =]

If it's for a race bike then think for a moment if you crash hard - what can you afford to replace next season.....versus the performace benefits it will most definitely reap for you. For instance.....you are riding a straight line and the guy behind puts his wheel into your rear der......do you have the ready cash to replace a toast Di2 rear der (and possibly frame too)? And if you don't have electronic will your racing performance/results suffer?.....not trying to come off negative - just a helpful reminder that there are many issues for each of us to prioritize.

n1klass, have a search - there are many threads discussing this.

The one common answer you will find for this question is (as tommasini said) "race what you can afford to replace".

Applies to anything really on a bike you're planning to race on.

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