Any big bike store will have a large variety of bike helmets depending on their primary intent. It can be confusing when you look at all the different types, shapes, colors, and features of different bike helmets. How are mountain bike helmets different from road bikes or even BMX bike helmets? We’re about to find out.
Mountain bike helmets differ from road bike and BMX helmets in the amount of cut in the back, built-in visor and ventilation holes, giving these cycling helmets a unique look over their road and BMX counterparts.
Let’s take a ride together into the world of mountain bike helmets and look in a bit more detail how they are both similar and different from other bike helmet types. Let’s get rolling.
In the world of biking, you’ve got a few different types of helmets, and some cross the boundaries with where they are used. Let’s start by identifying the different bicycle helmet types.
Road Cycling Helmets
The road cycling helmet is very similar to a mountain bike helmet with a couple of key differences. First, there often is no incorporated visor. Second, the back of the helmet is often very close to maintaining the same horizontal cut as the front of the helmet. A mountain bike helmet has a lower cut, as you will see after. (source)
Getting the correct fit on your helmet is critical. I made a YouTube video on measuring before buying. Link – https://youtu.be/BLSmTqDdzBo
The road bike helmet is designed with aerodynamics in mind. The helmets are not typically thick, engineered for maximum aerodynamic appeal yet maintaining enough ventilation so you don’t boil your brains out of your skull while you ride on the hot pavement.
BMX – Stunt Riding Helmets
These helmets are primarily used for BMX (bicycle motocross). It involves dirt and track/trick jumping and off-road dirt track racing, primarily.
The helmets are defined by a smooth overall design, maintaining a semi-uniform thickness around the helmet in terms of distance of outer helmet skin from your head.
BMX Track Racing Helmets
The dirt track BMX races typically use a design of helmet similar in many respects to that used by motorcycle riders. The design typically includes an additional jaw guard component either added to, or built into the body of a stunt riding style designed helmet.
Downhill Mountain Bike Helmets
Here we see a correlation in designs between BMX track racing helmets and mountain bike helmets. The marriage is the downhill MTB helmet design.
Downhill bike helmets are designed with a higher back cut than a dirt track BMX racing helmet. The reason is that oftentimes a downhill rider will tilt their head upwards to compensate for facing downhill. A helmet with a very low rear cut would become irritating in this situation.
Due to the nature of downhill mountain biking, these helmets usually include a jaw guard, as you can see in the image above.
The common mountain bike helmet is the most common type of all bike helmets. The design has been captured by many manufacturers to offer similar designs marketed merely as a bicycle helmet, but the root of the designs is obvious in terms of origin – they came from the MTB helmet.
Typical MTB helmets have either an attached or built in visor on the front. The rear has a lower cut than standard road bike helmets, and there are typically more ventilation holes as well.
Further to the ventilation, when compared with either BMX styles of bike helmets, the mountain bike helmet again has an abundance of ventilation holes comparatively.
Mountain bike helmets, unlike road bike helmets, are typically a bit bulkier and stand higher off the head than the road bike helmet. The reason is that the typical mountain bike helmet is thicker, that is, it stands out from the head more so than a road bike. Although aerodynamic, mountain bike helmets are not aerodynamically superior to road cycling helmets in most cases.
The thicker design allows mountain bike helmets to maintain a maximum amount of ventilation holes incorporated into the helmet design. Although most road bike helmets also have an abundance of ventilation, there are typically less ventilation holes on a road cycling helmet comparatively.
In terms of legal regulations, all bicycle helmets must comply with the same standards when it comes to protecting your melon. However, that does not mean that all helmets are created equal.
As mentioned previously, mountain bike helmets maintain the highest level of ventilation to accommodate for those difficult (and sweaty) uphill climbs. Both road and BMX riders do not face the same uphill climbs over off-road terrain as a mountain biker, and thus do not require the same amount of ventilation. Ventilation that could mean the difference between heat stroke and a fun ride. (source)
Mountain bike helmets offer a lower cut rear to the helmet than road bikes. This added protection helps in cases of crashes where the potential for lower skull injury from contact with sticks, rocks and other common mountain biking obstacles is present.
Another feature of mountain bike helmets that aids in safety is the added visor. The visor helps protect against branches in the eyes and also helps block the sun from blinding you on your ride.
I’ve written all about how visors help on riding. Read my article: Why Do MTB Helmets Have Visors
Unlike both BMX track racing and downhill MTB helmets, the stereotypical MTB helmet does not have a jaw guard. Some have detachable jaw guard accessories, but almost most MTB helmets do not have the guard included.
There is no rule that says you can’t use a BMX helmet or a road bike helmet for mountain biking. In fact, I’ve got several friends that ride both BMX track and MTB and use the same BMX helmet for both applications.
The downside to mixing applications of intended helmets usually comes down to comfort. The number of ventilation holes, the helmet coverage, and fit/feel while doing your ride are all integral to the overall experience and enjoyment of the helmet use.
Mixing applications may have other unintended consequences as well, depending on how well the helmet fits. In circumstances where you have a bumpy mountain bike trail, a semi-loose road bike helmet could wind up bouncing around too much and distract you from your ride. Best to not let a helmet cause an actual accident, my advice – stick with the helmet best suited for the intended sport or hobby for best results.
More Ways to Stay Safe On Your MTB
- Is there an art to falling? I say yes – find out why in – How to Fall Off Your MTB (and not get hurt)
- How many ways can you get hurt riding? Read 10 Most Common Mountain Bike Injuries (plus tips to avoid)
- Is It Safe to Ride Alone? A great article about being prepared.
- My knees hurt for a long time after riding. Find out how why. Is Mountain Biking Hard On Your Knees
David Humphries is the creator of DIY Mountain Bike. For me a relaxing day involves riding my mountain bike to decompress after a long day. When not on my bike I can be found wrenching on it or casting a fly on a small mountain stream. Read more about David HERE.