I tried on at a LBS the Genius 5 in regular and mega (I wear a 45). I don't think I will be purchasing the Genuis (the only one they had), but I am ordering a "lesser" Sidi online. The megas were a little loose, and the regulars a little snug. I tried one of those shoe-sizers that they had - my width looks to be a B.

Given that, can those of you with Sidis recommend which way to go for me? These are my first pair of clipless shoes, so I don't know how snug they should feel.

Thanks,
Scott

After reading a little more, I am becoming convinced that that B that I read was not correct. Is there a relationship between these letters and width of widest part of your foot in inches?

I wear a 10.5 shoe (I've been trying Sidi 45s). The width of the widest part of my foot is about 4.25 inches. On another chart I read that puts me in the D-E category. I'm confused.

myselg a bit loos feels good tight sucks. thicker socks fixes the first nothing fixes the second.

Hi Sco Jo,

How much room do you have above your big toe in the size 45? The "rule of thumb" actually works here, in that you should have a little less than one thumb width above your big toe to the tip of the shoe in pointy toe shoes and just about 1/2 thumb in round toe shoes.

Many conversion charts show size 10.5 American to fit 44 European. Perhaps a wide 44 like the Sidi Mega may be worth trying on. Most feet vary in size during the day, and also with hydration level. Proper fit in the ball of the foot seems critical, since the straps are designed to tighten down the arch of the foot.

I favor rather thin socks for cycling to get the best pull-up and evaporate sweat. I avoid 100% cotton socks since they hold sweat, and use nylon or poly-blend socks.

When I mount my cleat, I always make sure to have the center of the ball of my foot align to the center of the pedal axle. New shoes can change your saddle position both up/down and front-back. The common wisdom is to adjust height such that your leg never fully locks straight, and to adjust the front/back such that a plumb bob from the back of your knee cap will drop just slightly behind the center of the pedal axle. If you like to spin, push the seat back a little from this alignment. Knee damage is possible if you push the seat forward of this alignment.

I have a fairly wide foot, but I actually preferred the normal Sidis to the Megas (I bought Dominator 4s). I like my cycling shoes reasonably snug, and the Megas seemed to have too much toe room for me.

What sort of socks did you try them on with? I find that if I wear thicker cycling socks with my Sidis the snugness gets a bit extreme, whereas my old Specialized shoes are far better with a thick sock.

I have a WIDE foot, and the Megas are snug on me....just how i want them. if you want measurements I can take them, I wear a 11 wide normally but a 12 in regular shoes and 46 Megan in SIDI

I think I need the length of the 45 - I have 1/2 a thumb width at the top, maybe less. The box for the 45 also says 10.5. I have only worn them with regular athletic socks so far as I don't have cycling socks. Maybe if I try wearing them for more than a few minutes they will loosen, or are they pretty much how they will be? Should I try them with dress socks for now, or is that too thin?

dress socks remind me of cycling socks, but at the same time, a thick pair of athletic socks in the winter may be too snug then...how tight are you tightening the buckles? alot of this can be adjusted...you really have to work on those straps the first few times...

Hey PWRDbyTRD, can you measure the width of your foot at the widest point? I think I am in the D-E range, are you a multiple-E? Seems that's what most folks who wear the megas say they are from what I am reading. If you were on the border between widths, would you go up or down for a cycling shoe? Seems too wide can be fixed with thicker socks, but a little tight can stretch. This is a decent chunk of change for me, I really want to get it right.

BRB measuring time

I'm 4 and 5/8" across the widest part of my foot.

SIDIs are made of lorica or something...made to NOT stretch or deform...

Thanks!

Anyone else out there wearing Sidis willing to provide data? How wide is the foot? Megas or Regulars? Sorry to be a pain in the a$$, but these suckers aren't cheap and us newbies is clueless.

Just an FYI for you... Sidi Dominators 5 Mega size 46. I feel someone with a bit narrower foot could wear them.

Great info - didn't see your numbers until after my last post. Hey Stubacca, what about you - how wide are your feet? Sounds like you also might be in that in-between range. Gonna have to go back to the shop again. Wish they had something other than the $200+ version though.

Size 47, 4.5 inches at the widest point when standing, feet flat.

Paid $98 at REI on sale last year . Great shoes...

And you have the regulars, not the megas? Sounds like you got a great deal.

Find the size that fits you in the length, then try that size in the half size. The 45 fits me in the length, but is too narrow. The 45.5 is perfect. A little more material, the foot bed is the same. The mega is way too wide.

I usally wear size 11.5 normal width (I think that's D width). I have a pair of Sidi Zeta size 46.5 (the box says US 11.75). If the shop has a half size try those on as well. Sidi's half sizes don't change the length of the shoe. Rather, they widen the toe box and a fuller cut in the the forefoot.

Here's a quote from their site:

WHAT IS DIFFERENT ABOUT A HALF SIZE?
Half sizes are constructed on the same full size last of that model but with a fuller cut, especially in the toe box area.

Here's a link:

Sidi FAQ

I wear Sidi Genius Mega size 45.5. My feet are 4.5" wide (between size E and EE).
With a width of 4.25" I would go with the regular shoes. The nice thing about Sidi is that they have half-sizes available. Instead of getting the wide version you could go 1/2 size longer and probably get a better fit.

Sidis will stretch out to fit your foot. If the Megas are a touch loose now, they'll be really loose 5k miles down the road. I have a fairly wide foot and bought G4 Megas (also in a 45) a few years back that I ended up replacing with the standard G4 Carbons. The only time I ever wear the Megas now is when it's so cold that I need both a shoe cover and a think pair of smartwool socks.

Yup, regulars. Tried the megas, but I prefer the more snug fit of the regulars (probably too used to ski boots....).

Looks to me like air king and qpelpel are absolutely correct - I tried on the 45.5 today in the regular width (I had been looking at 45s and 45 megas). They were perfect for me. Thanks!!!

Aargh! Now I find that the "lesser" Sidis that I was planning on buying DON'T COME IN HALF SIZES. After all of that! Now what?