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Sidi Genius 6.6 Vent Carbon Shoes
Sale $240.00$399.95 $ 40% Off

Item # SID0110

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  • Black Vernice/White, 42.5 ($240.00)
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Item # SID0110


Comfort is a right.

Comparing the Genius 6.6 Vent Carbon Shoes to Sidi's flagship Wire shoe, you're bound to uncover numerous shared design features. You'll find the same carbon fiber sole, the same adjustable Heel Security System (HSS), and an identical intake vent system. In fact, the two really only part ways on a few points-- aesthetics, a closure system, and price.

Hailed as Ivan Basso's favorite shoes, the Genius 6.6 features a more traditional exterior design than the Wire. This is most apparent when examining the shoes most predominant aesthetic features, the closure system. In lieu of the Wire's Techno 3 buckle system, the 6.6 opts for Sidi's tried-and-true, two-way ratcheting Caliper Buckle. Assuredly, you've seen the Caliper Buckle imitated by lesser shoemakers, however, this design was invented by Sidi decades ago. The system allows for incremental adjustments, either pre-ride or on-the-fly, and it's further complimented by Sidi's take on two hook-and-loop straps. Not your standard Velcro, these two volume-controlling straps feature Sidi's patented High Security Velcro. So, you'll never experience any fraying, wear, or loosening of the Velcro over any period of time. Together, as a system, the three-point closure system ensures that you get the perfect fit every single time that you buckle up for a ride. And for those who prefer as snug a fit as possible, the shoe's tongue and instep strap have both been padded generously to allow for supreme comfort with tight buckles.

As we stated, the Genius 6.6 shares the same sole as the Wire. Based off of the Ergo 3, the 6.6 sole features the superlative vented carbon fiber. It shares the same construction method that Sidi developed with its Carbon Lite sole, yet Sidi has removed around 38 grams in the process. Even with the weight savings, you'll get the same kind of stiffness and razor sharp power transfer you've grown to expect from Sidi. And like Garneau's Ergo Air system, the vent inlet is at the toe. However, Sidi's system can be opened or closed depending on the temperature and your preferences. This, you can do on the bike if necessary. The airflow moves underneath and through the insole to cool your feet in sweltering summer temperatures.

Also returning from previous top-shelf offerings is Sidi's vastly improved Heel Security System (or HSS) to keep your foot positively planted in the shoe. By means of a small allen key, it's an adjustable, rigid composite band that closes the shoe more securely over your heel to anchor it in place around your Achilles. So, no matter how much power you're pouring into the pedals, your heel will stay in place inside the shoe. It's a detail that allows you to cinch down the straps of your shoes less tightly -- giving you more comfort along with more security.

With a degree of engineered flex in the Vent Carbon Sole, and a secure and slip-free heel, you won't have to worry about hot spots. And you especially don't have to worry about heat in the rest of your feet, either. With the Genius' combination of Lorica microfiber, ballistic mesh, and new Comfort Fit insoles, you'll receive comfort, a perfect fit, ample ventilation, and season-after-season durability.

The Sidi Genius 6.6 Vent Carbon Shoes are available in the color Black Vernice/white and in whole and half sizes from 39 to 48. Most sizes also have an Mega option available for those requiring a high-volume shoe. Please note that these shoes are only compatible with standard, three-hole road cleat systems.

  • Vented carbon fiber sole
  • Identical to the Wire, except for closure and aesthetic
  • Heel Security System
  • Caliper Buckle and High Security Velcro closure

Tech Specs

Upper Material:
[uppers] Lorica Vernice Microfibre, [ventilation] ballistic mesh
main strap with ratchet closure, 2 hook-and-loop straps
Sidi Comfort Fit
carbon fiber
Cleat Compatibility:
3-hole road
Recommended Use:
Manufacturer Warranty:
1 year

Size Chart

Recommended Sizing Guide

Men's Cycling Shoes
US SHOE SIZE5.566.577.588.599.51010.51111.51212.51313.514
Chrome 37.5 38 39 39.5 40 41 41.5 42 43 44 44.5 45 46 47   47.5   48
Diadora 38 39 39.5 40 40.5 41 42 42.5 43 43.5 44 44.5 45 45.5 46     
DMT 38   39   40 41 42 42.5 43 43.5 44.5 45 45.5 46   47 48  
Five Ten 37 38 38.5 39 40 40.5 41 42 42.5 43 44 44.5 45 46 46.5 47   
Fi'zi:k 38 39 39.5 40 40.5 41 42 42.5 43 43.5 44 44.5 45 45.5 46     
Gaerne 38 39   40   41 42 42.5 43 44 44.5 45   46 47 48   
Giro   39 40 40.5 41 42 42.5 43 43.5 44.5 45 45.5 46 46.5 47 48  
Lake 39.5 40 40.5 41 41.5 42 42.5 43 43.5 44 44.5 45 45.5 46 46.5 47 48  
Louis Garneau 38.5 39 39.5 40 40.5 41 41.5 42 43 44 44.5/45 45.5 46 47 48 49 50  
Mavic (US/EU) 5.5 / 38 6 / 38.7 6.5 / 39.3 7 / 40 7.5 / 40.7 8 / 41.3 8.5 / 42 9 / 42.7 9.5 / 43.3 10 / 44 10.5/ 44.7 11 / 45.3 11.5 / 46 12 / 46.7 12.5 / 47.3 13 / 48 13.5 / 48.7  
Northwave 37   38 39 40 40.5 41 41.5 42 42.5 43 44 44.5 45 45.5 46 47 48
Pearl Izumi 38 39 39.5 40 41 41.5 42 42.5 43 44 44.5 45 46 46.5 47 48 48.5 49
Shimano 38.5 39.5 40 40.5 41 41.5 42 43 44 44.5 45 45.5 46.5 47   49   50
Scott 38   39 40   41 42   43 44   45 46   47 48   
Sidi  39 40 40.5 41 41.5 42 / 42.5 43 43.5 44 / 44.5 45 45.5 46 / 46.5 47 47.5 48 48.5 49
Six Six One 38 38.5 39 40 40.5 41 42 43 43.5 44 44.5 45   46 47 48 49 50
Suplest 37 38   39 40 41   42 42.5 43 43.5 44 44.5 45   46   47
Vans 37 38 38.5 39 40 40.5 41 42 42.5 43 44 44.5 45 46   47   48
US SHOE SIZE5.566.577.588.599.51010.51111.51212.51313.514

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Avg. ride time: 8m per week
  • Average ride time is based on Strava activity over the last 3 months. Give your reviews credibility by connecting your account.

fantastic shoes

  • Fit: True to size

I haven't been this excited about a new pair of shoes since the 2nd grade. my last pair was mavic, which were comfortable and durable, especially for the $120 price point.

these shoes offer great stiffness in the soles, plenty of comfort without extra padding/weight/bulk, and the toe box is wider than average, which allows for a snug fit at pressure points without making your foot feel claustrophobic. while expensive (even when on sale) for most riders, I think these shoes are definitely worth it given superior comfort/performance.

Great Shoes

  • Fit: True to size
  • Size Bought: 48

I've been wearing Sidi cycling shoes for a long time. I think they are the best. I have a narrow foot and they tend to run narrow unless you get the wider option. The quality is great and I usually get at least 5 years of wear out of them. The soles are stiff and that's really nice compared to less expensive more flexible soles. They are expensive but worth it. I've got almost 1k miles on these new shoes and I like them.

Great Value

  • Familiarity: I've put it through the wringer
  • Fit: True to size
  • Size Bought: 42

This shoe is why people buy Sidi's. These are my 3rd pair of Sidi's for the simple reason no other shoe fits me better, has so many features and is made as well. A 42 fits my 81/2 EEE perfectly. I can get them snug yet they don't feel tight. The heel cup adjustment allows you to dial in a custom fit. Cleat placement is a breeze with minor adjustments thanks to the markings on the sole. The fourth screw hole enables you to replace cleats exactly where your old ones were. This version of the shoe has a vent in the front that can be opened or closed depending on the temp. Materials and build quality are first rate unlike the Fizik's which I tried. The inside of those were as coarse as sandpaper. I was comfortable in these shoes from day one. Although not the cheapest shoe out there you would be hard pressed to find a better made shoe with as many features. 100% satisfied.

Competitive Cyclist was a great help here since I went through 4 pairs of another brands shoe until I realized I was wasting my time. They took back the returns and paid for the shipping. Just a suggestion if you are buying shoes mail order. Get 3 or 4 pair at the same time. Return ones you don't like. It will save you time and money in the long run

The right fitting shoe!

  • Familiarity: I've used it once or twice and have initial impressions
  • Fit: True to size

I've searched and tried and whined about cycling shoes being too narrow, too small, too expensive, etc. I took a leap of faith and purchased the Sidi Mega Genius 6.6. Wide, comfortable, safe and stylish, these shoes are the best available. If your feet are wide you will enjoy these wonderfully comfortable shoes!

What is the best way to clean the mesh, keeping it as close to white as possible?

Excellent Long Distance Shoe

  • Fit: True to size

I ride long miles and needed a new pair of shoes after 25k miles in a predecessor pair of Shimano. I like a solid, stable, good-fitting shoe, and have found a few others that I tried before buying these to be too light and flexible, which in my experience can lead to discomfort on century-plus rides. These Sidi's are great, and the sale price ($325) is a decent bargain. Sizing-wise, I found them very true -- I was surprised to see someone say they run big. I'm an 11.5 US and the 45.5 fits great -- 46 would be too roomy. Highly recommended.

I won't stray again

  • Familiarity: I've used it several times
  • Fit: True to size
  • Size Bought: 43 1/2

I've been using Sidi's Genius 5 shoe for years now both for road riding and commuting. I probably have 4-5K miles on my last pair. So when I bought a new road bike and upgraded to Look pedals, I let the bike shop guy talk me into another brand of shoe to use exclusively for my weekend road rides. He suggested the velcro on the Sidi shoes would eventually wear out, so the wire system on the Specialized shoe would be better. Well it turns out that Sidi just makes a far better and more comfortable shoe. I would get hot spots and numbness on the bottoms of my feet within 45 minutes of riding, and would have to get off my bike and walk around to go for more than 90 minutes or so.

So I decided to cut my losses and invest in a new pair of Sidi's and never look back. So far I've only used the Genius 6.6 on my trainer (it's been a tough winter here in Boston) but they fit like a glove, the are super stiff, light, and breathable. I can't wait to finally get them out on the road, but based on my Genius 5 experience I am not the least bit worried about the velcro.

The only reason I give these shoes 4 stars is the price. They are a bit lighter than the Genius 5, have a stiffer sole, and they look way cooler, but are they really $250 better? Hard to say but I know that this summer when I'm 2 1/2 hours into a ride and my feet still feel great, I won't be complaining one bit.

I won't stray again

Worth the premium price

  • Familiarity: I've used it once or twice and have initial impressions

I bought these to replace my white Sidi Ergo 3, which also had a similar color combo, carbon weave sole, a vent, and a ratcheting top strap, but with 2 rotary tightening fasteners like on the current model Wire. The wire fasteners on the Ergo 3 worked, and the nylon wire surprisingly never broke, but I was never a fan of twisting to tighten, and found it a little awkward and gimmicky.

I replaced my Ergo 3 with these 6.6 Vent because I really like the ratcheting strap but personally find the 2 lower Velcro(R) straps more convenient, reliable, and intuitive to use. The carbon sole on the 6.6 Vent is extremely stiff, which I actually find to be highly comfortable in how efficiently it transfers power to the pedals. I leave the vent "open" for the hot Texas days, though I can't say for sure that I notice the difference. Could be because they are still new, but I feel like the footbed is more comfortable than my old Ergo 3s were. My first ride on the 6.6 Vent was a hot, brisk century, and I had no issues the entire ride.

These are not cheap, but for me, the combination of features and overall high-end materials and design justify the premium price. If I bought a 2nd pair as an alternate I would look at one of the more value-priced Sidi shoes which are probably also great for the money.

Avg. ride time: 2h 7m per week
  • Average ride time is based on Strava activity over the last 3 months. Give your reviews credibility by connecting your account.


  • Familiarity: I've put it through the wringer

I wore these for a hard 8000 miles season last year and am on my second with them. The shoes are super durable look decent, fit pretty darn good and are well ventilated. I have a longer second toe so I do have some issue with the fit as far as length. I imagine if you have normal feet these would totally rock your world. I will probably go semi to full custom next pair of shoes, but overall Sidi is a stand out brand that will make your cycle feet happy.

Just like Ivan Basso

  • Familiarity: I gave it as a gift but have feedback to share
  • Fit: True to size

Bought these for my dad who has worn a pair of Sidi's for about five years this pair. So far he has worn them on a couple of rides and says that they fit very similar to other Sidi's he has worn. He loves how the venting and how well air moves through. All in all it is a great quality Italian shoe; stiff, lightweight and well made would recommend this product.

Great Italian Quality

  • Familiarity: I've put it through the wringer

This is a superb pair of shoes. I purchased a pair back in the summer and love the quality and fit of these. They are very ventilated and i do not get hot spots when wearing them. I am a US size 11 and the 45.5 fit perfectly. They stay nice a snug on the feet and the straps are very easy to adjust. This is my second pair of Sidi's. The first pair lasted me 8 years so they have awesome quality. Just what you would expect from an Italian shoe.

Great Italian Quality

Too Big!!

  • Familiarity: I returned this product before using it

I recently found that normal shoes do not fit me well. I have wide feet. After trying a size 44 at a store I decided to order the 44 MEGA. When I received them I realized that they were too big. Competitive Cyclist does not have the 43.5 MEGA in this style so I order the Sidi 5 Carbon and I will see how they fit. They look like a really good shoe very disappointing they don't have my size.

The Best Road Shoe

    I have ridden Sidi's for the last 5 years. My first pair were Genius 5. I would rate them fair. These Genius 6.6 are excellent. They have addressed all the issues I had with the 5's. they are extremely well vented., they provide great side support where the 5's had none. The wide size fits my toe box perfectly without allowing me to swim in the rear of the shoe. This shoe actually fits American feet, not just Italian feet! I will keep buying these. 5 stars.