Hello. I've got some questions and freely admit, I only half know what I'm talking about. Please go easy on me.
For starters:

• I intend to change my current Shimano crankset for a couple of reasons, from 172.5 mm and 50/34 to 165 mm and 52/36.
• I want to get a quark. [eta - ok, I see I should think beyond quark. still interested in crank-based vs pedals, wheel hub, or single sided.]
  

It looks like one quark model will fit all shimano 6800 cranksets regardless of chain ring size. Is this true also for 6700? As in, does that D4 PM spider work with the 10-spd 6700? [eta - I now see the 6700 is 5 arm and the 6800 is 4-arm, so answer to this question is clearly NO.]

1. What if I "upgraded" to the 6800 crankset. Would the narrower chain I assume I'd have to get work with my 6700 derailleur and 10-spd cassette?
2. Or would I now need to get a new derailleur?
3. Also a new cassette? I believe ability to do this depends on what hub I have, right? I can't find a part # on it, just know it's Bontrager RL from 2013.

I don't exactly have a burning desire to upgrade my whole drivetrain right now, but suppose I could. And to help me consider this point, could someone tell me:

5. True or False - the Cannondale Slice year 2016 (purchased in Nov 2015 I assume it's the 2016 model) is not ITU legal (due I think to narrow seat stays). Ergo, I can't use it at say Powerman Zofingen?

Basically, I want the new PM on my other bike no matter what, but my interest in upgrading the drive train has to do with compatibility with my race wheels, for which the rear has an 11-spd cassette. Yes, I know I could move the 10-spd cassette over in the event I were in a non-Slice compatible race. But I'm just trying to understand my options.

Thanks!!

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