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As mountain bikers, we all know that we should wear a helmet and for the most part, we all do. But are we wearing the right helmet? Historically, the answer to this has generally been no. And that has become even more common in recent years.

As mountain bike technology has increased, the mountain bikes that everyday riders take to their local trails have become just as capable as the downhill bikes ridden by pros just 10 and 20 years ago.   As mountain bikes became more capable, the local trails that many of us ride on a daily basis became more gnarly. However, helmets were slower to evolve. Until recently, there have been two types of helmets: Open face and full face.

Open face helmets, obviously, do not protect your face and are generally much less substantial all around than a full face mountain bike helmet. On the other hand, they are light and cool, perfect for cross country rides and long grueling climbs. But as the descents from these climbs have gotten faster, more technical, and more dangerous, open face helmets left us at risk for some nasty injuries.

Full face helmets meanwhile provided outstanding protection but were generally too hot and heavy for anyone who actually had to pedal up a hill. As a result, they were used almost exclusively by downhill riders who shuttled or used a lift to reach the top of the mountain.

Enter the Convertible Mountain Bike Helmet

The answer to this was convertible helmets. Convertible mountain bike helmets are full face mountain bike helmets with removable chin bars. Without the chin bar, they become an open face helmet. This allows riders who earn their turns via long, difficult climbs to enjoy the light weight and comfort of an open face helmet while climbing, and the safety of a full face helmet on the descents.  

 

However, there were some drawbacks. Convertible mountain bike helmets were heavier than their non-convertible counterparts, owing to the extra materials used to attach and detach the chin bar. Furthermore, there are still a limited number of these available, and some of the earlier models had some issues that made them less attractive than they should be.  

 

Today, the top convertible helmets fulfill the promise of two helmets in one, delivering the safety of a full-on downhill helmet for the descents, and the breathability and security of a high coverage open face helmet when used without the chin bar. We believe that convertible mountain bike helmets are the future, and should warrant serious consideration if your riding involves climbing to earn your turns, or if you want a helmet that can operate as a great half shell while on your local trails and serve as a full-fledged downhill helmet for park days.

How Do Mountain Bike Helmets Work?

Mountain bike helmets are generally comprised of two layers: an outer, polycarbonate layer, and an inner layer made of eps foam. The hard, plastic outer layer protects the eps foam and allows the helmet to skid, rather than catching and whipping your neck around. Meanwhile, in the event of a hard impact, the eps foam will crush and/or break, absorbing some of the force of the impact. This force absorption is the main way that helmets protect your brain.

MIPS and Other Anti Rotational Features

A few years ago, a company named MIPS began making a bright yellow plastic liner, which quickly showed up inside of a few high-end mountain bike helmets. The idea behind MIPS was that traditional helmets did a great job of protecting heads and brains from direct, straight on impacts, but in reality, this is not the nature of most crashes. Most often, a helmet contacts the ground or another foreign object at an angle, creating a rotational force on the helmet, and by extension, your head. MIPS aims to solve this problem. It is attached to the helmet via small, plastic pegs. When a strong rotational force is exerted on the helmet, these pegs sheer away, allowing the helmet to rotate without whipping the head and neck with it.

 

Fast forward until today, and almost all high-end mountain bike helmets contain MIPS, or another technology aiming to solve the same problem.

 

We feel that anti-rotational safety is even more important in mountain bike helmets with a chin bar than it is in open face models. This is because chin bars tend to come to a point. This is great for aerodynamics, but it creates a convenient place for the helmet to “grab” the ground, causing the helmet to rotate or not rotate independently of the rest of your body. Therefore, it is essential to remove that rotational stress from your head and neck.

What To Look For:

Fit

The most important thing to consider when choosing the best mountain bike helmet for your individual head is…the shape of your individual head! Every head is shaped a bit differently from every other, and this makes it hard to say which mountain bike helmets fit well, and which ones do not. Some will fit certain people better, while others will fit other people better. Fit tends to be a bit easier to dial in with open face helmets because they incorporate a retention system. Full face mountain bike helmets are generally limited to one thinner and one thicker set of pads to dial in the fit.

 

This is an area where convertible mountain bike helmets have an edge over traditional full face helmets. Convertible models incorporate the retention system to perfectly dial in the fit, and then add a chin bar on for good measure. Typically, convertible helmets will also ship with a second set of cheek pads, to further help dial in the fit.

 

As always, trying helmets on is key. If you don’t have access to them locally, make sure that wherever you order from has a good return policy, so that you can exchange it if it doesn’t agree with your melon. Personally, I use BackCountry.com for this very reason. I will sometimes order two or three helmets, keep whichever fits best, and return the others using Back Country’s preprinted shipping labels. In fact, I recently went through a Fox Proframe, TLD Stage, and two Bell Super DH mountain bike helmets trying to dial in just the right fit and feel for my own head.

How We Judged

As always, we valued safety first and foremost. Second, we judged based on the weight and ventilation of a helmet, and finally, we consider its visor and any additional features that make a helmet more or less desirable.

  • Safety Tech 100% 100%
  • Chin Bar 90% 90%
  • Weight 80% 80%
  • Ventilation 90% 90%
  • Visor 100% 100%
  • Features 100% 100%

Pros

Epic protection in half shell mode

Best in class ventilation and visor

Fully certified downhill helmet with and without chin bar

MIPS Spherical

Cons

Pricey if not on sale

Weight: 487g

Helmet Weight with Chin Bar: 850g

Vents: 19 helmet, 2 brow ports, 4 chin-bar vents

Adjustable Visor: Yes

Use: Enduro, All Mountain, Downhill

  • Safety Tech 100% 100%
  • Chin Bar 60% 60%
  • Weight 80% 80%
  • Ventilation 90% 90%
  • Visor 60% 60%
  • Features 90% 90%

Pros

Lightweight

Leatt Turbine Technology

Well ventilated

Cons

Not as robust as other convertible helmets

Flimsy chin bar attachment

Limited visor mobility

Weight: 834g (size L)

Helmet Weight with Chin Bar: 750g

Vents: 23 vents

Adjustable Visor: Yes

Use: Enduro, All Mountain

  • Safety Tech 80% 80%
  • Chin Bar 70% 70%
  • Weight 90% 90%
  • Ventilation 90% 90%
  • Visor 100% 100%
  • Features 70% 70%

Pros

Lightweight

Tried and True Design

Best in Class Visor

Well Ventilated

Cons

Lack of MIPS spherical and other high end features found on the Bell SUPER DH

Not fully downhill certified

Helmet Weight: 433g

Helmet Weight with Chin Bar: 783g

Number of Vents: 23 helmet, 4 brow ports, 6 chin-bar vents

Adjustable Visor: Yes

Use: All mountain, Enduro

  • Safety Tech 100% 100%
  • Chin Bar 90% 90%
  • Weight 40% 40%
  • Ventilation 40% 40%
  • Visor 90% 90%
  • Features 80% 80%

Pros

The best protection on the market without a chin bar

Fully downhill certified

Cons

Too hot and too heavy without the chin bar

Weight: 800g

Weight with Chin Bar: 1100g

Vents: 20 vents

Adjustable Visor: Yes

Bell Super DH

Best Convertible Mountain Bike Helmet

  • Safety Tech 100% 100%
  • Chin Bar 90% 90%
  • Weight 80% 80%
  • Ventilation 90% 90%
  • Visor 100% 100%
  • Features 100% 100%

Weight: 487g

Helmet Weight with Chin Bar: 850g

Vents: 19 helmet, 2 brow ports, 4 chin-bar vents

Adjustable Visor: Yes

Use: Enduro, All Mountain, Downhill

Price: $299.95

What We Like: Epic protection in half shell mode, MIPS Spherical, Best in class ventilation and visor, Fully certified downhill helmet with and without chin bar

What We Don’t: Pricey if not on sale

The Bell Super DH is our top pick for the best convertible mountain bike helmet, and it really isn’t even close. It is lightweight (for a convertible mountain bike helmet), well ventilated, and offers unbelievable protection and safety features. In fact, we are so fond of this helmet that we feel it could easily compete for our top choice as an open face helmet without the chin bar and our top choice for full face mountain bike helmet with it.

The downside of the Bell Super DH is its list price of $299. However, it can frequently be found on sale between ~$210 and ~$260. And if you consider the fact that this helmet could save you from having to buy two separate helmets, it actually becomes a pretty good value buy.

This is the helmet that convinced us that convertible helmets are the future of mountain bike helmets. Finally, as the ultimate endorsement, after testing multiple helmets, I chose the Bell Super DH to keep my own head safe on the trails.

LEATT DBX 3.0 ENDURO

  • Safety Tech 100% 100%
  • Chin Bar 60% 60%
  • Weight 80% 80%
  • Ventilation 90% 90%
  • Visor 60% 60%
  • Features 90% 90%

Weight: 834g (size L)

Helmet Weight with Chin Bar: 750g

Vents: 23 vents

Adjustable Visor: Yes

Use: Enduro, All Mountain

Price: $239.99

What We Like: Lightweight, well ventilated, Leatt Turbine technology

What We Don’t: Not as robust as other convertible helmets, flimsy chin bar attachment, limited visor mobility

The Leatt DBX 3.0 Enduro helmet is yet another solid entry from Leatt. If you love the Leatt DBX 3.0 All Mountain open face helmet and the Leatt DBX 4.0 Full face helmet, then this might be the perfect helmet for you, as it brings much of what made both of those amongst our favorites.

 

We were not terribly confident in the seemingly flimsy chin bar attachment points, and it is not a serious downhill helmet like the Bell Super DH or Giro Switchblade. However, it is a lightweight and extremely well-ventilated option. If you want a convertible mountain bike helmet for the safety of a chin bar on tamer terrain, rather than for bombing the bike park and double black diamond routes, then the Leatt DBX 3.0 Enduro helmet is a solid choice at $239.

Bell Super 3R MIPS

  • Safety Tech 80% 80%
  • Chin Bar 70% 70%
  • Weight 90% 90%
  • Ventilation 90% 90%
  • Visor 100% 100%
  • Features 70% 70%

Weight: 433g

Helmet Weight with Chin Bar: 783g

Number of Vents: 23 helmet, 4 brow ports, 6 chin-bar vents

Adjustable Visor: Yes

Use: All mountain, Enduro

Price: $229.95

What We Like: Tried and true design, best in class visor, lightweight, well ventilated

What We Don’t: Lack of MIPS spherical and other high end features found on the Bell SUPER DH, not fully downhill certified.

Successor to the revolutionary Bell Super 2R, the Bell Super 3R is a great all-around helmet for trail riding in both open face and full face modes. The chin bar attaches solidly and easily enough, and it even shaves a bit of weight off of, and adds a bit of ventilation to, the burlier Bell Super DH.

 

While it can’t match the Super DH or Giro Switchblade as a fully certified downhill helmet, it is still a great option. It feels more solid than the Leatt DBX 3.0 Enduro and offers a much better visor setup. This makes it a very attractive choice if you want a convertible mountain bike helmet, but don’t plan on testing it out with serious gravity use.

Giro Switchblade MIPS

  • Safety Tech 100% 100%
  • Chin Bar 90% 90%
  • Weight 40% 40%
  • Ventilation 40% 40%
  • Visor 90% 90%
  • Features 80% 80%

Weight: 800g

Helmet Weight with Chin Bar: 1100g

Number of Vents: 20 vents

Adustable Visor: Yes

Price: $249.95

What We Like: The best protection on the market without a chin bar, fully downhill certified

What We Don’t: Too hot and too heavy without the chin bar

The Giro Switchblade, along with the Bell Super 2R was one of the first convertible mountain bike helmets on the market, and the Switchblade was the first to be fully downhill certified.

 

The Giro Switchblade is an extremely unique and heavy-duty helmet. It offers the best open face coverage of any helmet that we have reviewed. However, it is so hot and heavy without the chin bar attached, that we would probably opt for a lighter, cooler full face helmet if we wanted full-time cheek protection.

 

The Switchblade occupies a very unique niche, but with convertible helmets like the Bell Super DH matching it for safety, and full-face helmets like the Leatt DBX 4.0 providing light weight and cool full face options, there is less room for a helmet like the Switchblade than their once was.

We participate in affiliate programs to help us fund Gear Hacker. Some of the links in this website are affiliate links, which means that if you purchase a product using our link, we will earn a small commission. Don’t worry! This comes at no additional cost to you, and we will never base our reviews on whether or not we earn a commission off of a product. With that said, if you find our review helpful and decide to purchase an item we review, we would be very appreciative if you use our links to do so. It will help us bring you more awesome content in the future!