Looking for a new mountain bike helmet to go with your new mountain bike? There are a number of new technologies these days that make modern mountain bike helmets more affordable than they used to be. You also have the added benefit of getting many features that were only available on high-end models. But let’s be clear, there is no perfect helmet for everyone.
In this article, we’re going to do a quick rundown of the 6 best mountain bike helmets under $100, taking it from the most reviewed helmets on the market.
After reviewing MTB helmets, we’ll be talking about helmets in general to help you get started on the best search. The information given will focus on bike helmet shopping and what kind of information is included with a purchase. You’ll also find answers to some frequently asked questions.
Our Favorite Product
We could easily say the Smith Engage MIPS is the best overall mountain bike helmet but if we’re being honest, many of the helmets in this price range have similar features but serve slightly different purposes.
You might live in an area of the country where you prioritize ventilation over the weight of the helmet, or maybe you want full face protection over a half shell.
Any helmet off this list would be a great choice to get you shredding the mountain trails without sacrificing utility or safety.
Mountain Bike Helmets Comparison Table
|Troy Lee Designs
|A2 MIPS Sliver
|CPSC 1203, CE EN 1078, AS NZ 2063
|CPSC, CE EN 1078
|CPSC, CE EN 1078
Giro Fixture MIPS – Best Value
- Integrated MIPS Brain Protection System
- Roc Loc Sport fit system
- In-Mold construction
- Removable visor
- Reflective accents to improve safety at night
- Quick dry padding
- Slimline webbing
|Trail inspired design with a sleek look
|Extra plush padding making this a comfortable helmet
|Cleaning with alcohol will remove matte finish
|18 vents to improve ventilation and reduce sweat
|Some riders reported the universal sizing was too small
|Universal fit sizing to ensure a snug fit
|Straps around ears isn’t adjustable
|Chin strap doesn’t adjust enough for some
The Giro Fixture MIPS has all the safety features you need and is affordable too. It also looks great with a trail-inspired design and an appealing range of colors (13 to be exact) to suit your style.
The Giro Fixture MIPS helmet absorbs impacts well with its deep coverage of the back of your head, a breakaway visor and its MIPS lining that reduces energy transmitted to the brain. The outer shell twists independently to reduce glancing blows by affecting only part of your head without twisting your neck in uncomfortable positions.
The Fixture features a removable visor to help reduce snagging of the helmet in the case of a crash.
Fit & Sizing
The comfort is adequate and the Roc Loc fit system lets you quickly adjust it to make it even better. However, some riders have mentioned that the adjustment knob felt rather flimsy and was difficult to reach.
The chin straps on this helmet are sewn together at the junction, making them impossible to adjust around the ears. While other riders have complained that it’s difficult to adjust the rest of the straps altogether.
All of these features lead to an ergonomic fit that will be comfortable for most users and the universal sizing should give you a good fit right out of the box.
The combination of the EPS liner and the 18 ventilation ports will ensure that moisture is sufficiently absorbed and evaporated. If you’re traditionally a heavy sweater you may want to wear a bandana or headband to keep the sweat from dripping into your eyes.
The Giro Fixture no doubt has some shortcomings, but for the most part this is a feature-packed bike helmet under 100 bucks.
Troy Lee Designs A2 MIPS – Best Design
- Industry first dual density EPS + EPP liner
- Expanded field of view with support for goggles
- Comfortable half shell design
- 3 year warranty
|Comfortable and fits well
|No goggle stowage
|Velcro from liner can sometimes be felt on head
|Built by racing enthusiasts
|Visor can sometimes be hard to adjust if overtightened
|Adjustable visor is great for cutting down glare
The A2 Sliver is a mid range trail mountain bike helmet with a stylish shell that incorporates huge intake and exhaust ventilation ports, as well as the best head coverage of other helmets in this price range.
Trail and enduro riders will appreciate the ease of which you can adjust this helmet making it one of the best affordable helmets we reviewed.
This helmet has a revolutionary new design with a breakaway visor and an industry-first dual-density EPP + EPS liner to give you the coverage you need whether you’re plowing over speed bumps or tearing up the trails.
In addition to the MIPS liner, the A2 features a patent pending EPP + EPS liner that reduces impact from crashes and will help ensure that you’re able to get up from that gnarly crash and ride another day. There’s also an additional amount of frontal protection in this model over previous Troy Lee models.
The A2 also features breakaway visor screws that enable the rider to tighten the visor or completely remove it for aesthetics. In the event of an accident, the visor pops off before any additional stress is put on the neck.
Fit & Sizing
With the adjustment wheel near the back of the head, many riders are able to accommodate any sizing issues they have once they put this helmet on. With just a few clicks on the fit dial, you should have a snug helmet that looks amazing.
There is velcro inside the helmet that can cause some discomfort if not properly managed but the Pure Silver comfort liner should help alleviate that issue.
With the improved ventilation from previous designs, the A2 Sliver has exceptional airflow, which is critical if you live in hot or humid weather. With the 14 vents in strategic locations, you are sure to keep a cool head.
Smith Engage MIPS – Best for Eyewear
- MIPS rotational protection
- 21 vents for maximum airflow
- Comfortable lining that is lightweight & the webbing is low-bulk
- Multi-position adjustable visor
- AirEvac™ ventilation system prevents fog when used with Smith eyewear
- Includes Smith Crash Replacement Policy
|Designed for integration with Smith eyewear for venting and storage
|This mtb helmet is a little deeper than most
|Good weight distribution and shouldn’t strain neck
|Sits lower on the forehead than other brands, might impair vision for some riders
|Easily adjustable size with the rear wheel to dial in the perfect fit
|Some riders have reported some low wind noise while riding
With the Engage from Smith, they clearly believe in the importance of a stylish and great fitting helmet. Smith has done a great job hitting all the right features at a reasonable price.
The helmet’s construction provides excellent protection for the back of the head, and the 21 vents will keep you cool on hot days.
The Engage has Smith’s VaporFit™ system that provides a secure, custom fit with AirEvac™ channels to promote airflow and prevent fogging of your eyewear.
The Engage also features channels on the front of the helmet for eyewear storage, and a three-position visor that rotates to allow for goggle storage when your goggles aren’t in use.
As is the case with most helmets in this price range, the Engage includes the MIPS protection system. Rotational motion can cause some brain injuries, but with MIPS the brain remains protected because it moves and rotates less. The MIPS layer will slide 10 to 15mm in all directions during impact, instead of making the brain move or rotate as much.
Fit & Sizing
Most riders report that this helmet fits well for most head sizes. Just measure your head according to the size guidelines and you should be happy with the fit. No need to adjust up or down in size.
If it does feel a bit big, the rider can utilize the dial adjustment on the back of the helmet to cinch it down for a tighter fit.
The 21 vents really help prevent sweaty heads due to the increased airflow which will, of course, make for a more comfortable ride.
Since the company is well known for making eyewear, it should come as no surprise that several of their features include benefits for those that wear sunglasses or goggles. One of which is the anti-fog system that’s built into the helmet using channels.
Kali Protectives Alchemy – MIPS Alternative
- Utilizes LDL – Low Density Layer and Composite Fusion Plus technology to keep you shielded at all times
- Polycarbonate shell and in mold construction
- Micro-Fit closure system with 2 position height adjustment
- Locking buckle and sliders
|Very lightweight pc shell
|Less coverage in the back of the head
|Anti-microbial, moisture wicking pads are washable
|Not a MIPS helmet
|Shorter visor than other brands
|Lifetime crash replacement warranty
With many brands deciding to use the more common MIPS as their primary protection system, Kali invented their own based on research by their founder and safety team. So if you don’t believe that MIPS is the right protection for you, this is one helmet that will provide an alternative.
Kali started out with a liner that’s low-density (LDL) on the inside which helps their helmets better absorb the force from low gravity surface impacts.
Your helmet is there to prevent damage from occurring when you fall and hit your head.
You may find that after a few falls, your helmet will start to show signs of wear. A level of protection, called the foam liner, is usually built into helmets but Kali also includes the LDL. The impact from a soft or hard fall can do damage to the foam liner which in turn absorbs the force and prevents it from hurting your head.
It’s these soft, low-g hits, especially when received repeatedly, that turn into serious concussion damage to your brain over time.
The safety team at Kali Protectives is constantly looking for ways to improve the safety of their products. They created Composite Fusion which fused a shell and foam together to create a thinner and stronger helmet. Lighter and stronger, you’ll also find that this helmet also provides more protection for your head.
The ALCHEMY uses Composite Fusion and LDL to reduce the impact of any blows to the head to reduce concussions.
Fit & Sizing
Many riders had no issues finding the correct fit with this helmet. Just measure your head’s circumference at the widest point of your head to get the right size.
This helmet features fantastic ventilation with 21 vents to keep riders cool on hot days.
Demon United Podium – Best Full Face
- 13 vents to keep you cool
- Graphics and design by the Demon Team
- Fully adjustable and removable visor
- Injection molded polycarbonate outer shell
- EPS foam liner conforms to the shape of your head
|Great looking helmet
|Field of vision is not impaired by the sides of the helmet
|If wearing goggles, it’s possible that some fogging may occur in cold weather
|Great price for entry-level helmets
|The helmet shape may not be great for all head shapes
|CPSC certified for riding
|Several styles and colors to choose from
This is the only full face helmet that we reviewed in this price range and it’s a great one. The Podium by Demon United is designed for downhill riders looking to protect their domes (and faces) from gnarly crashes.
There are a lot of very lightweight trail-focused helmets on this list but this one falls into our price range and at 2 lbs, it’s not that much heavier but provides a lot more protection.
This particular version doesn’t come with a MIPS liner but it does have a super durable, injection molded polycarbonate along with an EPS foam liner that will prevent serious head injuries.
Fit & Sizing
Many riders claim that this helmet runs a bit small so it would be wise to grab a size larger if you’re worried about being on the edge of a size. Also, the company even acknowledges that the sizing is a little small for some. Just be sure to utilize the sizing guides and you should be fine.
The Demon United Podium Full-Face helmet has plenty of coverage to keep the sun out of your eyes, and your brain in your skull. With 13 vents strategically placed on the helmet you’ll be able to keep your head cool and focused.
No helmet that provides this amount of coverage will be completely sweat-free. Let’s be real; you’re going to sweat while wearing this. However, the face guard also has some venting to allow for additional airflow.
The liner inside is also washable so you won’t have to worry about it stinking too bad after wearing it in the hot summer.
Giro Radix MIPS – Best Ventilation
- MIPS protection
- 25 vents for maximum airflow
- Quick dry padding
- P.O.V. adjustable visor (15 positions)
- Includes limited 2 year manufacturer warranty
|The visor is the preferred length for a trail/enduro style rider
|Some riders who sweat a lot may get drips on their glasses
|Visor doesn’t impair vision
|The visor sometimes won’t stay in place
|The straps are high quality and don’t creep up after being set
|Helmet is a good size for those with wider heads
The Radix MIPS helmet is perfect for adventurers who want a perfect fit and to stay safe in different conditions. The ventilation also helps keep you cool and the adjustable visor keeps the sun out of your eyes. For bike helmets under 100 this one comes in at the right price and is a good helmet for all around use.
We may even be inclined to call the Radix the second best mountain bike helmet we reviewed.
The P.O.V. visor system allows the rider to adjust the visor with one hand, while riding, into one of the many positions. You can even store your goggles above your brow to keep them off your face.
The Radix comes equipped with a MIPS slip pane into Giro helmets that is designed to reduce the risk of concussion. They also help improve fit and comfort while making the helmet more secure. All Giro helmets are designed to dissipate as much impact as possible while exceeding the stringent safety standards of the industry.
This helmet also complies with the US CPSC safety standard for bicycle helmets for people age 5 and older as well as the CE EN1078 certification.
Fit & Sizing
The highly adjustable Roc Loc® 5.5 Mips system is included which allows the rider to customize the fit for enhanced stability and extended comfort while still providing added protection from rotational forces in the event of an angled impact crash.
Giro helmets come with the Wind Tunnel ventilation system, which helps maintain a steady cool temperature inside the helmet by providing constant air circulation. This model includes 25 vents as well as internal channeling.
This elaborate design combines active vents in the shell of the helmet with channels inside of it to keep the air flowing over your head while forcing out old and stale air. It’s been shown that it is the most effective way to go with helmet cooling, and you can feel the difference every time you ride.
How To Find the Best Mountain Bike Helmets Under 100 Bucks
When you’re looking for a mountain bike helmet under $100 you’d think that you’d be missing out on a lot of features that the more expensive and best mountain bike helmets have.
Fortunately, that’s not the case anymore as many brands have brought the price point down and has added several higher end features like MIPS, lightweight frames, an EPS foam liner and increased ventilation.
Understanding The Different Types & Styles Of Mountain Bike Helmets
There are many types of helmets for mountain biking and you need to make sure that you choose the right mountain bike helmet for your needs. Some helmet styles are designed specifically for downhill riding while others are designed for trail riders.
There are two main types of helmets: full face and open face.
Full-face helmets provide the most coverage and protection, but they can be hot and uncomfortable in warm weather, especially if they have poor ventilation.
Open-face helmets, or half shell helmets, provide less protection but they are cooler than full-face helmets. These protect the top of the rider’s head, the back of their head, and sometimes the sides of the head and ears.
There are also several main styles for mountain bike helmets that are more suitable for different types of riding.
Trail helmets are your most common type of mountain bike helmet due to the popularity of trail riding. These helmets feature a visor that is usually adjustable and provides an area to mount your goggles when not in use. The number of ventilation ports is usually lower as well but still provide good protection for the head.
XC type helmets often have extended coverage which is good as this will protect the vulnerable areas of the head better. This makes the MTB helmet a bit heavier and limits ventilation but adds to rider safety.
Enduro is a mountain biking genre that mainly consists of cycling up trails (often on very technical trails) before descending back down, often on downhill graded slopes. Therefore, it’s common to want a full-face helmet for maximum protection. The only difference might be to consider a convertible helmet that has a removable face guard or a visor with some adjustability.
Downhill biking is a form of mountain biking which often includes racing downhill with jumps and drops. Proper downhill helmets, or full-face helmets, as well as arm, leg, and padded body armor are needed for these types of races. The best mtb helmet for downhill mountain bikers is a full-face helmet that provides maximum protection as it will be needed in the event of a high-speed crash.
Other helmets that we won’t cover, but you should be aware of, are the BMX helmet and road helmets. These two helmets offer protection in different ways than your standard MTB helmets.
Most Important Considerations for MTB Helmets
The two most important considerations are making sure you have the right fit and to be sure the helmet will provide enough protection to keep the rider safe.
A helmet should fit snugly on your head so that it doesn’t move around while you’re riding and should stay firmly in place in the case of a crash. It should also cover as much of your head as possible – the front, back, top, sides, and your face (for full-face helmets) – to protect all parts of your head from injury in a crash.
We’ll discuss both of these topics in further detail below.
How To Get The Proper Fit For Your Mountain Bike Helmet
Make sure to get a helmet that you will actually be comfortable wearing in order to make sure it will do its job during a crash. Getting the right fit is crucial to ensuring that you have a comfortable experience wearing your bike helmet for hours at a time.
- Start with the head circumference:
In order to find your head size, wrap a flexible tape measure around the largest part of your head. This should be at about an inch above where your eyebrows are on your face. If you don’t have a flexible tape-measure, use a piece of string (not too tight) and then measure that string with the yardstick. Use this measurement to find what size helmet you’ll need.
- Adjust the tightness:
Most helmets have an adjustment wheel on the back of the helmet to allow the rider to create a snug fit. In some cases, you can find helmets that allow for removable foam liners to create adjustments in fit.
- Buckle and tighten the chin strap:
The straps on the side of the helmet should go over your ears creating a v-shape under each ear. Some helmets allow you to adjust the depth of these straps as well.
- Last step:
Snap the chin buckles together and open your mouth. The final fit shouldn’t be too tight that it’s annoying but it should cause the helmet to press against the top of your head as your mouth opens. If it’s uncomfortable then loosen the strap.
Helmet Protection & Safety
Cycling helmets consist of similar components to that of mountain bike helmets. The outer shell is made of plastic & the inner lining usually consists of high-grade styrofoam. When these pieces are all put together, the helmet helps to protect against potential head injury.
Additional advancements in head protection have spawned a few new technologies in the industry to reduce the rotational forces of impacts that can cause brain injuries.
The additional cost for these technologies might just save you from severe head injury out on the trail. Some of the common technologies found in helmets are MIPS, WaveCel, Spin, and LDL/CFP.
What is MIPS Technology and Why is it Important?
MIPS stands for Multi-directional Impact Protection System. MIPS features a low friction surface that redirects rotational effects by allowing the impact-absorbing foam liner to rotate slightly during impacts. Most manufacturer’s have integrated MIPS with the helmet’s retention system to reduce weight, increase safety, and still produce a lightweight helmet.
Outer Shell Design
In most modern helmet designs, you’ll notice that the outer shells are made from a polycarbonate shell which are smooth and slick. This is to prevent neck injury by allowing the helmet to slide off of objects and not stick to them causing friction.
Features of Helmets
Many helmets share the same minimum feature set. Major features include lightweight components, improved ventilation, a polycarbonate shell and great protection are some of the most common. Keep in mind when you’re looking for a bike helmet under 100 bucks that all the helmets we reviewed in this article had these features as a baseline.
Cheap helmets tend to have less flashy features but still need to meet the industry standard for providing protection from brain injury. One of those standards is from the Consumer Product Safety Commission.
These products don’t necessarily need to include advanced features but if they don’t provide enough extra protection to protect the user’s head then that’s basically a deal breaker.
Beyond safety standards, some products also include other beneficial features like a detachable visor, removable face guards, mounts for LEDs or GoPro cameras, rear and side reflectors and more.
Some of the technological advancements in helmets even include built in transponders or NFC chips that include the rider’s blood type or medication allergies. Bike helmets under 100 dollars don’t typically include these features.
Now that we’ve reviewed all of these helmets, it’s important that we stress that our favorite mountain bike helmet under $100 is still the Smith Engage helmet with MIPS protection.
It has the most features that will not affect your riding (only improve your riding) while still providing the right amount of protection to ensure you come home with your brain intact. In addition, it’s also one of the most comfortable helmets we reviewed.
Being from a sunny, warm climate, it has two of the things we need. It has great ventilation and it’s designed to accommodate your eyewear while riding.
When it comes to choosing a helmet, just remember that the best mountain bike helmet isn’t always the most expensive helmet. In our reviews, we saw that sometimes the midrange product had better safety features but in other cases it could be more worth it to go for a well-known brand name that you trust.
If we were to give you one piece of advice, spend as much money on the best mountain bike helmet that you can. This isn’t a piece of equipment where you should cut costs. You get one brain and you need to protect it from concussions and other forms of damaging head trauma.
Do you need a different helmet for mountain biking?
Mountain bike helmets are designed specifically for the demands of the riding genre. Downhill riders generally need the most protection but some cross-country and trail cyclists also look to them for protection. Always wear a helmet when you’re mountain biking, no matter which style.
Can a road bike helmet be used for MTB?
Yes, you can use a road bike helmet for mountain biking. Both road helmets and MTB helmets are designed to protect your head from a crash but understand that each type of helmet has different features that, depending on what kind of riding you typically do, can lend more protection or comfort.
Should a mountain bike helmet have a lot of vents?
Helmet airflow dynamics are complex, so the best way to test it is with a ride on a hot day. Most riders do not need extreme vents. These are only necessary in hotter times, and the ordinary vents on cheaper helmets are more than adequate for most people. This leaves more foam padding to cushion your impact in the event of a crash.
Does a MIPS helmet make a difference?
Studies have shown that the MiPS and SPIN helmets have been successful in reducing the risk of brain trauma and injury by up to 54%. In many cases, having this extra safety technology does make a difference in the amount of trauma a rider’s head sustains in a crash.
When should you replace a MTB helmet?
A MTB helmet should definitely be replaced after a crash. If no crashes have occurred, a good guideline is to replace the helmet every 3 years. Over time helmets sustain tiny impacts and the EPS of the helmet degrades over time and is less able to deal with the impact from a crash.