• Sidi - Ergo 4 Carbon Mega Cycling Shoe - Men's - Black
    Sidi - Ergo 4 Carbon Mega Cycling Shoe - Men's - Sole
    Sidi - Ergo 4 Carbon Mega Cycling Shoe - Men's - 3/4 Front
    Sidi - Ergo 4 Carbon Mega Cycling Shoe - Men's - 3/4 Back
  • Sidi - Ergo 4 Carbon Mega Cycling Shoe - Men's - Black
  • Sidi - Ergo 4 Carbon Mega Cycling Shoe - Men's - Sole
  • Sidi - Ergo 4 Carbon Mega Cycling Shoe - Men's - 3/4 Front
  • Sidi - Ergo 4 Carbon Mega Cycling Shoe - Men's - 3/4 Back
Sidi - Ergo 4 Carbon Mega Cycling Shoe - Men'sView Larger Image

Sidi Ergo 4 Carbon Mega Cycling Shoe - Men's

35% Off
$259.99 $399.99

Item #SID007U


Tech Specs

Upper Material:
Lorica microfiber
2 Tecno 3 buckles, 1 hook-and-loop strap
Twelve Carbon Composite
Cleat Compatibility:
3-bolt road
Recommended Use:
road cycling
Manufacturer Warranty:
1 year

Just the right fit.

Euro brands have a reputation for cobbling slim, sculptured shoes that remain tantalizingly off-limits to cyclists not blessed with the delicate feet to match. Before you write off Euro brands completely, slide your foot into the Sidi Ergo 4 Carbon Mega Shoe and experience a slipper with expert European construction and a platform that actually accommodates your taller instep and wider-than-average forefoot.

Sidi blends beloved features from throughout its line to create the Ergo 4, so if you're familiar with the brand, you're likely to recognize things like the Tecno 3 buckle system and Adjustable Heel Retention Device. The Tecno 3's dual ratcheting buckles provide micro-adjustability across the length of your foot for a contoured, secure fit that works for your foot. A wider platform shouldn't translate to a sloppy, loose fit, and Sidi unsurprisingly succeeds at striking a balance between the two with the Ergo 4. To match the heel of the shoe to your foot, tighten or loosen the adjustable heel to establish a secure fit that won't slip or waste power when you stretch out of the saddle mid-climb.

Underneath, the full carbon composite sole handles power transfer, creating a rigid medium through which to transfer power from the engine to the frame. A full carbon shank surrounded by nylon-reinforced carbon achieves a balance of slight flex for comfort with uncompromising rigidity during punishing efforts.

  • Sidi road shoe craftsmanship on a wider platform
  • Carbon composite sole blends rigidity and flex
  • Forgiving nylon for comfort, carbon shank transfers power
  • Durable Lorica upper resists weather and wear
  • Adjustable heel cup provides slip-free fit
  • Secure, customizable fit from dual ratcheting buckles

Very comfy!

  • Familiarity: I've used it once or twice and have initial impressions
  • Fit: True to size
  • Size Bought: 41.5 Mega

My feet are in the normal to wide area in width (but not volume) in the toe box, but with a bit of a flatter arch area, necessitating a wider width there. A 42.0 regular Ergo 4 can fit me in the toe box, but these Ergo 4 Mega's (in 41.5) provide me more width and comfort in the arch area (the slightly roomier toe box is not bad either, as I can tighten to my liking). Plus, these Ergo 4's have the ability to adjust the heel area too.

I picked these Ergo 4 Mega's after having tried on the lighter Shimano RC-9's in Wide (these were decently comfortable, but second to Sidi's comfort overall and with less adjustability), Specialized Torch 3.0 (no wides, so was narrow for me), and the lighter Specialized S-Works 6.0 in Wide (this wide was still narrow for me). Comfort >> weight here.

Overall, these Sidi's felt like the right shoe the moment I slipped it on, making me think that no break-in period was required. Shout out to Graham Dewart for all his help with my purchases and fitting.

Sidis are a favorite

  • Familiarity: I've used it several times
  • Fit: Runs small

Had to buy these in Wide. Tried the wire push but way too tight. This was the best option I could find from Sidi that came in wide. Wish they made the top tier shoes in wides. Why not Sidi?? Anyways, these things are still great. Had an old pair from back when SPD was the only option and they took a beating. These will last, like the heel adjustment and toe vent option. Newer wire dials are awesome for fit. Ordered a half size up from my normal and perfect. I run just below actually needing wides normally so these gave me plenty of room to put a Sole thin orthotic insert. Been riding an older version of the Fizik R3 Uomo which I also find very comfortable, good toe box. These Sidi have better power transfer and feel better on longer rides though. Like that the parts are replaceable too. As long as they do not improve our pedals again for awhile I should be good to go for the foreseeable future with these.

Contrary to the "runs slightly small"

  • Familiarity: I returned this product before using it
  • Fit: True to size
  • Size Bought: 45.5

Contrary to the "runs slightly small" this shoe is more true to size than stated. The Mega fit is really much wider than expected. If you have Fred Flintstone feet then Sidi Mega is for you. I thought I had wide feet at 10.5 EE. This Shoe is more like EEEE width

Sizing is tough, but

  • Familiarity: I've used it several times

once you get the right size, they are the best, but it takes a few tries. Buy two if unsure.

Sidi Ergo 4 Mega shoes.

  • Familiarity: I've used it several times
  • Fit: Runs small
  • Size Bought: Large

I had high expectations that my feet would fit more comfortably in these almost $400 shoes. But, alas, that was not the case. As one ages, one looses the arch in their feet, consequently lengthening the foot. I purchased a 1/2 size bigger than what my foot measured, hoping that my toes on my left foot would not rub into the toe box. The shoes just aren't that wide, even though they are advertised as an EE/EEE when one buys the Mega style. The shoes are incredibly well engineered and manufactured to offer the most comfort and performance possible. It's just my feet are now different then they were just two years. ago. I love the adjusting system on the shoes; really pro looking! Sidi doesn't recommend replacing their sole inserts but my toes were getting numb while riding with theirs so I purchased a pair of gel inserts and installed them into the shoes, preventing my toes from becoming LESS numb. Have your feet measured on a Brannock Device before purchasing these shoes so that you will know exactly your size and then convert that size in a European fit.

Looking for a wide road shoe.

  • Familiarity: I've used it several times
  • Fit: Runs small

I bought these shoes as I have been a Sidi fan for over a decade and I really like their shoes' performances. I had purchased a pair of Sidi Ergo 4 46.5 Mega shoe in hopes that that width would alleviate the rubbing of the tip of my second to the last toe to the top of the toe box. The Mega width, EE/EEE is plenty wide for flattened feet. Now, as I use this newer size, I have some pain in the second to the pinky toe but it's not from rubbing the toe box; it's from the toe gripping the bottom of the stiff sole. I am going to resolve my unique problem and I still highly recommend Sidi Mega width shoes.

Best Shoe Ever

  • Fit: True to size
  • Size Bought: 42.5

I've had foot pain for years as a cyclist. Over 60 miles and I had to stop and take off my shoes for 10 minutes. Yesterday I rode 100 miles in the Sidi Ergo Mega with zero pain!


I have just bought a pair like yours and am still experiencing toe rubbing pain. I wish these shoes were super wide!

comfortable shoes

  • Familiarity: I've used it once or twice and have initial impressions
  • Fit: Runs small
  • Size Bought: 48 mega

Once you get over spending that much for a pair of shoes, they really are quite good. I replaced the inner soles with ones a little more padded and have been riding comfortably since. My last pair of shoes were Lake's and liked the larger toe box. To get the same kind of fit on the Sidi's, I had to order the Mega. For normal shoes, I don't wear wides, but in the cycling world, apparently I have very wide feet. I look forward to logging lots of miles with these.


  • Familiarity: I've put it through the wringer
  • Fit: Runs small
  • Size Bought: 45.5

I'm 190cm (~6'3), 95kg (~210#), 11.5EEE feet with one foot about a half size larger than the other. For race day I've got the Sidi Wire Vent Carbon in a 46, top performance but not my favorite shoe for 100k+ rides. I went to the Ergo 4 Carbon Mega in a 46 for those 4-8 hour days in the saddle to get more comfort. Very happy with that decision but the 46's were a bit too roomy. Got the 45.5 and it is spot on. The silver lining is I use the 46's as a winter/foul weather shoe as the extra room allows heavier socks and more "wiggle room" to keep the toes from freezing. If you've got "frankenfeet" like I do, wide forefoot, narrow heel, high instep, hammer toes, heel spurs you'll probably like the Mega. I did 160k in the 45.5's right out of the box and was comfy from start to finish. These are not quite as stiff as the Wire Vent Carbon but for training, long days in the saddle, and long road races these are the trick for me. I prefer the "Techno 3 Push" buckle of the Wire Vent Carbons to the Techno 3's on these but there is an easy solution for that. I've bought spare buckles and will convert them over. Best shoes I've had in 25 years.

Larry, I am currently wearing sidi 6.6 mega. I have a 48E sized foot. I live in Florida so I wanted to get some wire air vented. Mega fits fine, I'm on the edge of it being wide, regular sidis are usually a touch tight. Do the wires have any extra room in them?

Finally! Comfort & Performance

  • Familiarity: I've used it once or twice and have initial impressions
  • Fit: True to size
  • Size Bought: 46

I have the Sidi Wire Vent Carbon, also in a 46, great race day shoe but not so comfortable for long days in the saddle. I've got "Frankenfeet", narrow heel, wide forefoot, high instep, high arches, hammer toes, ... really hard to fit. These Ergo 4 Carbon Mega's, out of the box, 100k ride, comfortable, roomy in the toe box but not sloppy, no hot spots, no pain, no numbness, ... dancing shoes. I pulled the stock innersoles and have put a set of my trusty SuperFeet Yellow innersoles in and expect that will be even better, will let you know!

Sidi's are the best!

  • Familiarity: I've used it once or twice and have initial impressions
  • Fit: True to size
  • Size Bought: 46

Bought these for my husband for his birthday and he has been surprised by their fit. He has wider feet and these are fantastic! Quality is top notch too.


  • Familiarity: I've used it several times
  • Fit: True to size

I had the misfortune in life to develop bunions after 40. I still run marathons and go on 5-6 hour long rides. It is a blessing to find running shoes in EE. It is not so easy to find wide cycling shoes. I usually buy the next size up and find some comfort- still after 5 hours on the saddle, my dogs ache! I own Specialized, Bontragers, and
Lakes. I recently purchased a pair of Sidi Ergo Carbon Megas. After a 2 and half hour ride- these shoes felt like they are worth every penny. Super comfortable and I was able to dial them in to get just the right fit. I hope cycling shoe makers make wider shoes for those with wide feet- or in my case bunions. Over 25% of the population have these kinds of issues- that is a quarter of the market! Back to these shoes- love them so much, that I ordered another pair of Megas. Those last 20 miles of a century ride can really put a damper on the experience. My Sidis will make long rides comfortable. I highly recommend these shoes! Molto bene Sidi!!

beautiful - meant to order the ones that were speed play compatible

I couldn't agree more. I am similarly afflicted with feet that have been beaten up playing ice hockey, downhill skiing, and cycling for most of my life. I really like my Sidi Wire Vent Carbon's for racing but for training rides and long days in the saddle the Ergo Carbon Mega's are the best, finally, comfortable, high performance cycling shoes for my tired old "frankenfeet"!! If you've got wide/tough to fit feet, these are great!

Even better than the Genius models.

  • Familiarity: I've used it once or twice and have initial impressions
  • Fit: True to size
  • Size Bought: 43 Mega

I've worn Sidi Genius Mega shoes almost exclusively for the past 15+ years. Prior to that? I wore Sidi Genius regular fit shoes ... essentially, I've been wearing Genius shoes since the original buckle, the original sole, and since they only had one Velcro strap. I don't think it gets much more dedicated than that.

Light, stiff, and form fitting, no shoe has ever fit my feet as well, which is why I keep replacing older Genius shoes with newer ones ... until now.

For my most recent pair of shoes for 2017, I opted for the Ergo 4 Mega. Same fit as the Genius shoes, but with a pair of Sidi's Tecno 3 dials instead of the buckle and one of the Velcro straps.

Initial impressions are that they fit exactly the same as my older Genius shoes, but with a bit finer adjustability at the top of my foot. I'm also digging the Adjustable Heel Retention Device at the back of the shoe. It's not like heel slip was ever a problem in the Genius shoes, but it's even less of an issue in these.

I'm looking forward to spending a lot of hours in these shoes.

My only quibble? The insoles are almost nonexistent. As I've gotten older and my arches have collapsed, I need more a little more underfoot support inside the shoe, so I've had to start using aftermarket insoles.

That said, I've still never found another shoe with an upper that better conforms to the shape of my feet or that cups my heel as well with no slip than Sidi. Since the way a cycling shoe's upper fits is just as important what's underfoot, it's going to take something amazing to convince me to change.

Sidi does not recommend putting into their shoes any after market insoles. How did this work put for you?

@Jim Corriere I've used both Specialized insoles in my Sidis for several years and have never had any issues; I'm currently using the Giro Supernatural Fit Kit (https://www.competitivecyclist.com/giro-sn-footbed-x-static-kit?s=a), and again have not had any issues.

Love these shoes

  • Familiarity: I've put it through the wringer
  • Fit: True to size
  • Size Bought: 45.5

These are my first Sidi shoes and I'll never stray. These are the first cycling shoes that are actually comfortable right out of the box. I'm so impressed. These have great amount of room in the toe box and good volume. More importantly, they have arch support. Usually I have to buy a 46 and then add insoles to a shoe that never fits correctly. These are also hugely adjustable. I didn't experience any issues with the tongue and was dialed in by the end of my first ride. I have put 500+ miles on them since and absolutely love these shoes.

Awesome shoes!

  • Size Bought: 43M

I always come back to Mega sidis for my feet.

Great for Regular-Wide Feet

  • Familiarity: I've put it through the wringer
  • Fit: Runs small

I now have a couple of hundred miles on these shoes. The increased width of the Ergo is perfect for regular to wide feet. I tried the Wire Carbon but they were WAY too narrow!! Really well built shoe. I switched from a Specialized FACT Carbon. ORDER A FULL SIZE UP IN THESE SHOES! I wore a 46 in the Specialized. Ended up with a 47 in the Sidi Ergo. Only real issue is the serrated edge of the tongue. Sort of digs into the face of your ankle for the first couple of rides. Once it is broke in I didn't even notice it. Well worth the money in my opinion! Very satisfied.

Just to add to albert's review, I also found that the tongue digs into your ankle. I had to cut the tounge in two spots to alleviate this issue.

The Sidi tongue has little slits where the tongue can be cut to customize the fit; the owner's manual even shows this ... so it's a feature, not a bug.


Cycling Footwear
35.5   4
36   4.5
36.5   5
37   5.5
37.5   6
38 5 6.5
38.5 5.5 6.5 / 7
39 6 7
39.5 6.5 7.5
40 6.5 / 7 8
40.5 7 8 / 8.5
41 7.5 8.5
41.5 8 9
42 8 / 8.5 9.5
42.5 8.5 9.5 / 10
43 9 10
43.5 9.5 10.5
44 9.5 / 10 11
44.5 10 11 / 11.5
45 10.5 11.5
45.5 11 12
46 11.5  
46.5 11.5 / 12  
47 12  
47.5 12.5  
48 13  
48.5 13.5  
49 14