Measuring my foot I’m about 10.75 inches which equates to 273mm. Mavics size chart says I need size 9?!?!?!?!? I haven’t put on a size 9 shoe since middle school. Am I missing something here?
Mavic Shoe Size Chart
I can tell you I definitely go small in Mavics compared to others. My Sidi road shoes are 43.5 but my Mavic Tri-Heliums are 42-2/3.
To put it another way, according to that chart, my 42-2/3 Mavics equate to a US-men’s size 9 shoe. Yet my walking-around shoes are size-10 - snug – and my running shoes are size 10.5
Just to confuse matters for you, once you have one that fits your foot, double check you can achieve the required cleat position on those shoes…
Mavic’s cleat holes are a long way forward relative to for instance Shimano or Northwave… (run a little back toward the heel) with say Sidi taking the middle ground in that respect…
Just so you don’t get caught out…
I run in 46-47.5 shoes and cycle in 45 - except for Mavics, where I’m a solid… 44.
I’ve found that Shimano and Mavic is pretty much similar, maybe Mavic is running a little bit smaller. I moved up a size for my Mavic road shoes anyway becuase I want to cope with the bloating of the feet when the hours seems to be endless during some days! 
/CE
Is too much width a bad thing? Seeing as we aren’t sliding our feet side to side, does the comfort of extra width hurt performance?
In my experience, Mavic shoes are not for people with wide feet. I wear Shimano Wide and Sidi Mega in a 44.5 (about 9.5 US). I’ve tried Mavic in a 9.5, 10, and 10.5 and they were all way way too narrow for my feet.
The mavic was a bit too narrow so I ordered the mavic maxi which is now just a bit too wide so I can slide my feet around a little bit from side to side
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