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At the outset of the MX helmet project, Alpinestars product philosophy was applied and a set of specific objectives set: - Create the most advanced, protective and performance enhancing helmet possible.

- Primary objective: protection - to create the most high performance protection possible.

- Secondary objective: to give excellent ventilation, comfort and reduced weight.

Alpinestars approach to the creation of the advanced technology in the Supertech M8 draws on its depth of experience from over half a decade of world class innovation across the spectrum of motorsports and especially, its deep rooted commitment to motocross. As with all other categories of technology that Alpinestars has mastered, bringing a new, highly complex, product to fruition requires specialist experience and know-how and a project plan led by the best brains in protection development.

Hence Alpinestars Helmet Development Department was created and given the brief to research and develop the most protective and most comfortable possible motocross helmet. The goal was to allow riders to push the limits of performance, benefiting from confidence inspiring safety technology, reduced weight distribution to minimise muscular effort in the neck, shoulders and back and improved physiological and cognitive performance with a supremely well-fitting and well ventilated construction, optimizing comfort while riding.

The design is coherent to Alpinestars philosophy and shares distinctive themes with other products in the portfolio; a smooth, attractive, profile which is streamlined and free of any external channels and features that might act as a load point in an impact, or compromise the overall integrity of the construction. The surface curvature promotes reduced friction on impact, allowing deflection and the most efficient transfer of energy to protect the rider's head from direct force to the skull and referred to the neck and spinal column. The aperture is designed to accommodate a wide variety of goggles and the air vents in the shell are located to maximize ventilation efficiency.

The S-M8 shell has been profiled with performance as a priority and with a design style that identifies the profile of the helmet and its sculpted surface as uniquely'Alpinestars'.

Another key feature is the S-M8 shell sizing solution; each helmet fit size has its own appropriate shell size to deliver the most anatomical solution for the wide variety of fit needs worldwide.

Safety: Supertech M8 Construction

Shell construction utilizes a highly advanced molding technology with a multi-composite combination: uni- directional carbon composite with aramid layer that gives significant radial strength around the shell, preventing compression but allowing controlled deflection for reducing transmitted impact energy, and providing critical penetration protection.

This combination of layers is given even greater performance with an epoxy resin bonding that offers the best possible strength and energy management; limited outer shell deflection means the energy spreads wider and is better absorbed by the EPS liner.

The result of the unique shell lay-up process employed in the S-M8 construction results in extremely effective impact protection. With a fully equipped helmet testing facility, within Alpinestars Racing Development Center, an exhaustive impact research program has resulted in the Supertech M8 returning linear and oblique impact performance which far improves upon current helmet regulation standard limits. For direct, linear, impact by an average magnitude of 41% and for rotational acceleration, oblique, impact performance by an average of 48%.

S-M8 in four anatomical shell sizes.

The Supertech M8 shell construction is optimized to offer best fit across the range of four size options. Shell sizes are manufactured in small, medium, large and extra-large to ensure that riders have the correct fit which not only improves comfort but, most importantly, the effectiveness of the helmet in an impact.

The Supertech M8 liner construction combines with the shell to offer highly efficient impact energy management.

Formed with a multi-density EPS polymer, the energy absorbing layer gives an inner helmet profile which soaks up impact forces dissipated over the outer shell at the point of an impact and provides a shape offering a close and comfortable fit.

The energy absorption performance of the S-M8 is substantially improved by a four section construction that allows for specific densities of polymer to be prepared for different zones around the helmet lining. Not only is energy performance improved but also fit and comfort.

Patented A-Head fitting height and angle adjustment system.

The Supertech M8 incorporates a patented system to allow the helmet to be tuned exactly to the riders preference for the height and angle at which the helmet sits on the head. This unique technology allows for an ultra-specific set-up that can be adapted for the type of riding and the rider's preference.

With a micro-adjustable pad that is connected to the helmet inner shell, it is possible to raise or lower the helmet fit and also, to tilt the helmet forward, or backwards.

Unique, patented, visor release system is another key attribute incorporated into the design of the Supertech M8.

Visor release is a key part of overall protection performance in the helmet and a major influence on the distinctive, flush, design of the outer shell profile.

Alpinestars has developed a unique visor release system which, while ensuring the mounting is held securely in place for riding over the most extreme terrain and any track conditions, provides exactly the right level of resistance to ensure the visor detatches from the helmet shell if it is subjected to a significant impact - no matter what the angle.

The S-M8 visor release mechanism is conceived to avoid the inherent weaknesses in other types of anchoring systems. Maintaining shell integrity is vital for safety and with the possibility of multi-directional forces impacting on the visor, separation at the critical point of loading reduces potentially damaging leverage and rotational accelerations that refer injury to the rider's neck and spine.

Collarbone protection is an important design feature of the Supertech M8 helmet shell base profile.

The base of the S-M8 has been sculpted to give a relief section, where the bottom profile is raised to clear the collarbone (Clavicle). Also, incorporated into the area of the base pad, where it sits over the rider's collarbone, is an energy absorbtion pad; a more flexible compound rubber section which allows deflection when it contacts the Clavicle.

The Supertech M8 chin-bar is formed with polypropylene which, by allowing for a degree of lateral deflection, further improves impact protection for the collarbones.

Post-crash protection mechanisms are also a key feature of the Supertech M8 design, allowing rapid and safe intervention if the rider has suffered a major impact.

Multi-Directional Impact Protection System: MIPS.

MIPS is incorporated into the Supertech M8 to reduce rotational motion energies that impact the helmet causing damaging gyration force to be transmitted to the brain.

A low friction 'slip' layer is incorporated into the Supertech M8 helmet, between the comfort padding layer and the multi-density polymer energy absorption shell. When energy is impacted upon the helmet, causing a rotation force, the MIPS layer allows for movement of the inner absorbtion layer to damp and re-direct the energy before causing significant acceleration stress to the brain. This mitigates the causes of brain injuries, such as concussion.

Emergency Release System (ERS).

The side cheek padding of the S-M8 can be extracted efficiently and safely, while the helmet is still on the rider's head, to allow ease of removal by trackside support and medical staff.

The Supertech M8 is also designed to allow a helmet 'Eject' inflation system to be fitted into the inside crown of the shell.

Along with the ERS padding removal, 'Eject' allows for emergency removal of the helmet, without putting load on the rider's spine.

Chin-strap: Wider than certification requirement: 26 mm for comfort and produced with a woven poly yarn to give a soft'hand' feel that connects securely with a double D-ring.

Weight: Reduced by design while allowing the Supertech M8 protection to be class-leading.

Weight is both a factor in riding performance and safety in a helmet and to ensure the S-M8 offers the ultimate in weight saving performance enhancement, the material selection, preparation and construction of the helmet has been rigorously analysed for weight to strength and energy absorbtion properties and a strict analysis of all the components used in the Supertech M8 finishing.

Weight of S-M8 is 1300g for size Medium (ECE) - 1360g for size Medium (DOT)

Ventilation is a key feature of the Supertech M8.

Heat mapping tests have resulted in specifically designed ducting which produces a positive flow into the helmet over and around the rider's head, improving comfort while riding and reducing the on-set of heat stress in extreme conditions.

The visor design of the S-M8 is also an integral part of the ventilation system as it is profiled to direct airflow, acting as a channel to concentrate and smooth the flow into the shell. The Supertech M8 liner design is formed to optimize airflow channeling around the rider's head before being extracted from the S-M8 through rear exhaust vents to ensure positive pressure is maintained with constant airflow while riding.

Hydration system compatibility.

The Supertech M8 helmet lining design includes canals which allow a tube to be incorporated on either side of the shell. This is a feature extensively tested by Alpinestars rally raid and enduro riders enabling convenient fitting and connection to a hydration system.

Interior lining comfort.

Removable liner cover is washable and features a cool-max fabric interior and anti-bacterial talent yarn for long- lasting freshness and quick-dry performance between riding sessions.

Helmet features TPE coating washable surfaces to improve maintenance and increase durability. Additional cheek pad set offering increased thickness of +5mm, for tighter fit adjustment - available separately.

Accessories included with the Supertech M8.

Soft bag.

The Supertech M8 Certifications.

The Supertech M8 helmet versions conform to both DOT certification and ECE homologation for use worldwide.

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Helmet Sizing

Helmet Sizes - General

How to Measure for Helmet Sizing

Measure the circumference of your head by positioning a tape measure in the middle of your forehead, wrapping it around above your ears and around the back of your head to its widest point. If you have longer or shorter hair, there may be some need to over or undersize. The general idea is to achieve a comfortably tight fit, remembering that a helmet will give a little in time. Compare the measurement in centimetres with the chart below:

Kids S: 47-48cm
Kids M: 49-50cm
Kids L: 51-52cm
XS: 53-54cm
S: 55-56cm
M: 57-58cm
L: 59-60cm
XL: 61-62cm
2XL: 63-64cm



Glove Sizing - General

How to measure your glove size

Measure the palm from left to right across its widest part excluding the thumb. The measurement in centimetres will indicate your size of gloves.

Adult Glove Sizes - General

XXS: 6cm
XS: 7cm
S: 8cm
M: 9cm
L: 10cm
XL: 11cm
2XL: 12cm
3XL: 13cm
4XL: 14cm
5XL: 15cm

Youth Glove Sizes - General

XXS: 3cm
XS: 4cm
S: 5cm
M: 6cm
L: 7cm


Mens Clothing Sizes

Mens Clothing Sizes - General

Mens Clothing Sizes - KTM

Shirts & Pants Chest (Inches) | EU Size Jacket | EU Size Waist (Inches) | Height (cm)
XS: 31-34" | 46 | 28" | 164-170cm
S: 34-37" | 48 | 30" | 168-174cm
M: 37-40" | 50 | 32" | 170-179cm
L: 40-43" | 52 | 34" | 175-185cm
XL: 43-46" | 54 | 36" | 180-189cm
2XL: 46-49" | 56 | 38" | 184-192cm
3XL: 49-52" | 58 | 40" | 188-198cm
These values only serve as a guideline. The sizes required may vary depending on height, build and muscle/fat volume.


Mens Shoe & Boot Sizes

Mens Shoe & Boot Sizes - General

UK: 5 |5.5 |6 |6.5|7 |7.5|8 |8.5 |9 |9.5 |10 |10.5|11 |11.5|12
EU: 38 |38.7|39.3|40 |40.5|41 |42 |42.5|43 |44 |44.5|45 |46 |46.5|47
US: 6 |6.5 |7 |7.5|8 |8.5|9 |9.5 |10 |10.5|11 |11.5|12 |12.5|13
cm: 23.5|24 |24.5|25 |25.5|26 |26.5|27 |27.5|28 |28.5|29 |29.5|30 |30.5

Mens Shoe & Boot Sizes - Alpinestars/ KTM

English 5 6 7 8 9 10 11 12 13 14 15
European 39 40.5 42 43 44.5 45.5 47 48 49.5 51 52
American 6 7 8 9 10 11 12 13 14 15 16
Mens Shoe & Boot Sizes - Fox

English 6 7 8 9 10 11 12 13 14
European 40 41 42.5 44 45 46.5 47.5 49 50
American 7 8 9 10 11 12 13 14 15


Ladies Clothing Sizes

Ladies Clothing Sizes - General

UK US EU Bust (Inches) Waist (Inches) Hip (Inches)
6 4 34 30 22 33
8 6 36 32 24 35
10 8 38 34 26 37
12 10 40 36 28 39
14 12 42 38 30 41
16 14 44 40 32 43

Ladies Clothing Sizes - KTM

Order Size UK Size Bust (Inches) Waist (Inches) Hips (Inches)
XS 6 30-31.5 23.5-25 34-35.5
S 8 31.5-33 25-26.5 35.5-37
M 10 33-34.5 26.5-28 37-38.5
L 12 34.5-36 28-30 38.5-40
XL 14 36-38 30-32 40-42


Ladies Shoe & Boot Sizes

Ladies Shoe & Boot Sizes - General

English 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8
European 34 35 35.5 36 37 37.5 38 38.5 39 39.5 40 41 42
American 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10 10.5
(cm) 21.5 22 22.5 23 23 23.5 24 24 24.5 25 25.5 26 26.5


Boys Youth Clothing Sizes

Boys Youth Clothing Sizes - General

Boys Size Age Chest (Inches) Waist (Inches) CB Sleeve* (Inches) Height (cm) Weight (Stone)
Kids X-Small 5 Yrs 22 21 21 102 2st 7lb-3st 3lb
Kids Small 6 Yrs 24 22 23 114 3st 3lb-3st 13lb
Kids Medium 8 Yrs 26.5 24 25 127 3st 13lb- 4st 9lb
Kids Large 10-12 Yrs 29 26 27 140 4st 9lb-5st 5lb
Kids X-Large 12-14 Yrs 31.5 28 29 152 5st 5lb-6st 6lb

Boys Youth Clothing Sizes - KTM

Order Size Chest (Inches) Height (cm) Age
104/3T/XXS 23-25 99-104 3 Yrs
116/4T/XS 25-27 111-116 4-5 Yrs
128/5T/S 27-29 123-128 6-7 Yrs
140/M 29-31 135-140 8-9 Yrs
152/L 31-33.5 147-152 10-11 Yrs


Boys Youth Shoe & Boot Sizes

Youth Shoe & Boot Sizes - General

English 11 11.5 12 12.5 13 13.5 1 1.5 2 2.5 3 3.5 4 4.5
European 29 29.7 30.5 31 31.5 33 33.5 34 34.7 35 35.5 36 37 37.5
American 12 12.5 13 13.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5
(cm) 16.5 17 17.5 18 18.5 19 19.5 20 20.5 21 21.5 22 22.5 23
Youth Shoe & Boot Sizes - Alpinestars/ KTM

English 10 11 12 13 14 1 2 3 4 5 6 7
European 28 29 30.5 32 33 34 35.5 37 38 39 40.5 42
American 10 11 12 13 1 2 3 4 5 6 7 8
Youth Shoe & Boot Sizes - Fox

English 10 11 12 13 14 1 2 3 4 5 6 7
European 28 29.5 30.5 32 32.5 33.5 35 36 37.5 39 40 41
American 10 11 12 13 1 2 3 4 5 6 7 8


Girls Youth Clothing Sizes

Girls Youth Clothing Sizes - General

Girls Size Size Chest (Inches) Waist (Inches) Sleeve (Inches) Hips (Inches) Inseam (Inches)
X-Small 1 33 25 29 35 29
Small 3-5 34-35 26-27 29.5-30 36-37 29-29.5
Medium 7 36.5 28.5 30.5 38.5 30
Large 9 38 30 31 40 30
X-Large 11-13 39.5-41 31.5-33 31.5-33 41.5-43 30.5


Girls Youth Shoe & Boot Sizes

Girls Youth Shoe & Boot Sizes - General

English 8 8.5 9 9.5 10 10.5 11 11.5 12 12.5 13 13.5 1 1.5 2 2.5
European 26 26.5 27 27.5 28 28.5 29 30 30.5 31 31.5 32.2 33 33.5 34 35
American 9 9.5 10 10.5 11 11.5 12 12.5 13 13.5 1 1.5 2 2.5 3 3.5
(cm) 14.5 15 15.5 16 16.5 17 17.5 18 18.5 19 19.5 20 20.5 21 21.5 22


Baby Clothing Sizes

Baby Clothing Sizes - KTM

Order Size Chest (Inches) Height (cm) Age
68/6mo 18.5-20 63-68 6 Months
80/18mo 20-21.5 75-80 18 Months
92/2T 21.5-23 87-92 2 Years

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