Castelli Sale—Save 25% or More on the Latest Apparel »
Sale $299.99 $369.95 19% off

Item # KSK000D

Select options
  • Select options
  • Black, M ($299.99)
  • Black, L ($299.99)
  • White, L ($299.99)
  • Red, M ($299.99)
  • Red, L ($299.99)
  • Black/Lime, M ($299.99)
  • Black/Red, M ($299.99)
  • Black/Red, L ($299.99)
  • 100% Guaranteed Returns
  • Free Shipping on orders over $50

Item # KSK000D


Checking out some of the pro tours this season probably revealed to you the rising popularity of suspiciously smooth-looking aero helmets in the peloton. Just check out the heads of Team Sky, Drapac, and others next time, and you'll catch a glimpse of a great lid you can now call your own: the Kask Infinity Helmet.

So why go all aero-head? Some research shows that overall drag on the bike can be reduced by as much as an amazing 14% when opting for an aerodynamically optimized helmet, as opposed to a heavily scooped and ventilated one. Makes sense, given the surface area your helmet presents the air. With this knowledge, Kask designed the Infinity to spare every joule of energy you can crank out, while still enabling plenty of airflow to prevent an overheated dome — after all, helmets have been designed with vents for a reason, too. The solution? The Infinity's front vents can be quickly and easily opened or closed single-handedly via a switch on the top. Open up for the climbs, seal up for the descents, the sprints, the chases — it's your call.

The Infinity isn't just a one-trick pony, however. It's a real helmet, first and foremost, intended to protect. The polycarbonate outer layer of the helmet is bonded directly to the polystyrene core for better shock absorption upon initial impact. Should secondary impacts come into play, Kask's ingenious Frame technology is a web of Kevlar-like material that forms a lattice within the helmet's core to prevent it from fragmenting. Of course, no Kask would be a Kask without being exceptionally comfortable, too. The smooth, Eco-Leather straps, thick and antimicrobial CoolMax removable and washable padding, Kask's rubberized Micro Dial retention system, and its easily-adjusted strap Dividers mean dialing in a comfortable fit is always easy and fuss-free.

The Kask Infinity Helmet includes a helmet bag and comes in the colors Black/red, Lime, Red, White, and Black. The only sizes available are Medium and Large.

  • Aero-optimized shape
  • In molding technology (polystyrene core joined to outer polycarbonate layer)
  • Frame technology (Kevlar-like material prevents fragmenting)
  • Antimicrobial Coolmax padding is removable and washable
  • Micro Dial retention system
  • Adjustable front vents
  • Eco-Leather chin strap

Tech Specs

Shell Material:
Impact Foam:
Fit Adjustment:
Octo Fit
Claimed Weight:
[size M] 260 g
Recommended Use:
road cycling, triathlon, time trial

Size chart


Vertigo, K50 EVO, K50 MTB
Head Circumference18.9-22.8in
K10 MTB, K31 Crono, K10 Race
One Size
Head Circumference20.9-24.0in
How to Measure:
Measure around your head where your hat would fit comfortably.

Reviews & Community


Write a review

    Add a:
  • Photos
  • Videos

No file chosen

Rather attach a photo from your computer?


Product Fit:

Runs smallTrue to sizeRuns large

Add Your Size


Height (ft, in):

Weight (lbs):

Size Purchased:

Only jpg, jpeg, png, gif or bmp files please.

Submit ReviewCancel
Avg. ride time: 8h 12m per week
  • Average ride time is based on Strava activity over the last 3 months. Give your reviews credibility by connecting your account.

Dont love it.

  • Familiarity: I've put it through the wringer
  • Fit: Runs large
  • Size Bought: medium and large

first the pros: I bought this for winter riding. It is definitely warmer than any other helmet I've worn in the cold. It is a little quieter though not a real selling point for me. I do like that you can vent it if you need to. It does look super cool! I mean this thing is the prettiest girl at the prom! EVERY rider checks this thing out and let's face it, as cyclists, we like that.
The con: it really does have tons of different adjustments and i have spent tons of time trying to adjust it. I have 2 months and 1000+ miles in this thing and still don't have it dialed in enough to glow about it. I bought the med and large to fit it right The medium actually fit perfect but the straps were too small. The large is just a little too much for me. I find it to be a large, bulbous, heavy helmet. I spend 5-7 minutes fiddling with this thing at the beginning of every ride after i have spent 10 minutes adjusting it before i leave the house. Some sunglasses fit ok with it others don't at all. On my head, this reminds me of an entry level $60 bell. I really expected better considering all the reviews and the price.

I will continue to wear it through winter because it's warm but i cant wait to put it away in the sping.

Avg. ride time: 31m per week
  • Average ride time is based on Strava activity over the last 3 months. Give your reviews credibility by connecting your account.

Kask Infinity Helmet

Cool helmet with some issues

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

I saw this helmet on GCN and the guy said that it was really good for cold weather because you can l close the vent making it aerodynamic AND keep the wind out. So I bought the helmet. I always wear a size large in every helmet I've ever owned. When I tried it on, it would not go over my head. Darn! What the heck, right? I returned it. My LBS was surprised it would not fit because he said it was actually pretty roomy. He asked, "Did you open it up?" I asked, "What"? "Did you pull the adjuster knob down"? So, there's an adjustment knob assembly at the back of the helmet that you need to pull down and open up so that you can get it on your head. Duh-oh! When I pulled it down and opened to adjustment knob, it fit like a charm. The problem in that the first time I wore it, when I went over bumps, the air vent door rattled! It sounded like something in my front end was rattling - but it was the helmet door! The good news is, it's comfortable, fits well, looks pro, and gives you a ventilation option. The bad news: it rattles when you hit a bump.

The Kask Infinity Helmet is not the same style per the picture if you look at solid black and the black/lime. Why is that?

Hi T Robert T, the black/lime photos show the front vents exposed with the slide open. The black helmet shows it closed.

Not all seasons

    This helmet is one of the best I ever had, but it is not for all seasons as some people claim online. What is true! Very comfortable! Light! And you will lokk like a pro! :)

    Great helmet BUT...

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

    First of all, the helmet does not run small. It is just shaped for people with round heads and not oval. I have a really big round melon :) and all Kask helmets seem to fit me very well. However, I am running in a major issue with the helmet that I am not sure what to do about. The rear adjustment strap does not stay in the position and constantly gets loose. My other Kasks do not have that problem. Since I used it several times now, I am not sure I can still return it to Competitive Cyclist and even if I do I am not sure if a new helmet would solve the issue. Thoughts?

    Really Small

    • Familiarity: I returned this product before using it
    • Fit: Runs small
    • Size Bought: Medium

    I measured my head three times, ordered a medium and it was WAY too small. Rechecked the size on the box and the tag inside the helmet, both gave the same size in cm for head diameter. Maybe take them up on the $7 try them all deal. I'll post again when I get one that fits.

    I got a large today and I could uncomfortably get it on my head - kind of. So my advice is to go up 2 full sizes. If your head is a medium go for a XL. I'm giving up.

    In fairness to Kask, I want to add to my reviews and comments about size. My head shape is what they call a long oval for motorcycle helmets. I think the problem with the Kask helmets being so far off is that they are molded for people with round or oval heads, which I think is the majority of people. So they don't work for me, but they might if you have the appropriate head shape. Too bad the manufacturers don't have a way of telling consumers whether their helmets are round, oval or long oval.

    No place for a ponytail!

      Wanted to like this helmet but it just didn't work with a ponytail! Loved the optional vent though!
      I have the original Vertigo which is very ponytail friendly so I might go back and order the Vertigo 2.0!


      • Familiarity: I've put it through the wringer

      I have had this helmet for a couple Months. I'm in Fl so I was concerned about the venting however it vents good for an aero. You can feel it cutting threw the wind with the vents shut and the air rushing in when open. A friend of mine felt he was at a disadvantage when I wore the helmet so much so, he went out and bought one also. He has not worn another helmet since. He rides with the vent closed only. I do open and shut mine all the time. I bought the Giro Synthe and will wear that in the heat but when it's cool or when riding with the fast guy's this is my helmet out choice.