Sidi Genius 6.6 MEGA sizing

So i’m getting new shoes for my duck-like feet and these so called “MEGA” Sidi’s look promising. I’ve pissed around with the print-out sizing guide from their site so i’m just looking for a second or third opinion.

So basically what I want to know is - If you got them, what size feet are you in normal trainers and what size Sidi’s do you own?

Yeah I could go into a shop and try some on but i’d feel like a bit of a wanker getting some poor mope fetch me a few sizes only to walk out after teasing him some commision knowing I would NEVER pay the LBS price.

Note that i’m only interested in people who bought the MEGA sized ones.


first piece of advice with bike shoe sizing. ALWAYS TRY THEM ON. this aint the soft sneaker game where slop is ok. bike shoes work infinitely better when they are fitted correctly. try as many brands as you can on… that way you will have a good diea of what fits and how.

believe me, when you are a few hours deep into a ride and discover you get hotspots you will be frustrated about sinking a couple hundred $ into a pair of shoes that dont work or even worse cause physical damage like knee injuries. when you find a brand/model that fits well you will be very happy.

for those that have spent regular time in the mountains, id equate it to finding properly fitted snowboard or ski boots.

IMO its ok to try shoes on and not buy, for my last pair of bike shoes (sidi dominator megas) i tried on about 10-12 pairs of shoes in about 4 stores. i was upfront with each store saying ‘i’m looking for new shoes, im trying on as many as i can to compare different makes/models and then im going to think about what works best for me.’ in some cases the stores made offered me deals on the shoes that i found best in their store, and these were closer to the online price than you might imagine.

i have small, wide feet so it became pretty obvious that i needed a wider shoe… lakes, sidi megas (bullet and doms) and some nikes were in the running. i think there was another brand but i cant remember it now (it was a very euro brand - so largely unheard of outside there)

with regards to your original question: i’m a mens US8.5 in vans and fit a 42 in sidis.

but ultimately… go find somewhere that stocks them, try them on and try a few other brands on too… good stores will help you with proper fitting as well.

apologies if you already know about bike shoe fitting… this is one area where i feel like off-the-shelf buying doesnt work out well, and can have negative impacts.

FWIW - I wear a 8US in VANS/Converse etc. I take a 42 in Shimano but a 43 in SIDI cos they’re a tighter fit.

I just bought some of those shoes in the mega fit as I have very wide feet. I take a size 9.5 in ordinary shoes which is about a 43 however in cycling shoes I take a 44.

I have bonts - size 44 and have had shimano road shoes in a 44. I tried a size 44 sidi ergo 2 to work out the right length and then took a punt and got the wide fit sidi 6.6.

They are very comfy and I’m extremely happy with them.

My advice - find a mate who has a pair in your size and try them on first before you part with cash.


is this in the mega or normal?

i’d agree the normals feel tighter than the equivalent size shimanos, but it seemed (to me) to be across the forefoot and not in length. hence the reason why they do a mega option.

I echo the other comments here. I wear 43 street shoes and the 43 Sidi’s are borderline uncomfortable, 44 was much better. 43.5 would be ideal. Maybe look at half a size.

Ideally try some on in a store, find what fits, balk at the price if the salesman gives you the hard sell and them buy them from CRC for a fraction of the price.

Normal sizing not Mega… no clown feet here !